ACNP 61st Annual Meeting: P1 - P270 Poster Summaries (2023)

Erica Vieira*, Etienne Sibille, Sanjeev Kumar, Ana Paula Mendes-Silva, Madison Bak, Tarek Rajji, Breno Diniz

Centre for Addiction and Mental Health, Toronto, Canadá

Background:Chronic inflammation and neurodegeneration are well-characterized pathogenic factors in depression and dementia, particularly in late-life depression and Alzheimer's dementia (AD), and a potential therapeutic target for treatment. An important mechanism linking inflammatory and neurodegenerative biomarkers to specific cell activation and communication is the release of extracellular vesicles (EVs). EVs are nanometer-sized vesicles, have specific membrane proteins, and contain nucleic acid (microRNA) and protein cargo. EVs can be released from cells under a variety of conditions, including chronic inflammation and stress, and show significant age-dependent differences in their pro-inflammatory profile. In addition, brain cells such as neurons and astrocytes release electrical vehicles that can be extracted from plasma samples. Electric vehicles can be divided into three groups based on their size. The best-studied vesicle is the exosome, which ranges from 30 to 150 nm. Exosomes are considered cell-specific vesicles, and assessment of their content can provide more detailed information about biological changes in specific cell types than assessment of total plasma content.

Brain cell-derived exosomes, such as neuron-derived (NDE) and astrocyte-derived (ADE) exosomes, can easily cross the blood-brain barrier and be identified in the periphery. The role of NDEs and ADEs is an emerging area of ​​research and a tangled path involving the dialogue between the CNS, neuroendocrine and immune systems. Although studies in AD have advanced, the role of exosomes in LLD is poorly understood. Furthermore, LLD is multifactorial and may be a prodromal condition associated with neurodegenerative diseases including AD, frontal temporal dementia (FTD) and vascular dementia (DV).

Therefore, exosome signature may share common pathways and molecules between LLD and AD. So far, there are no studies in the literature comparing NDE and ADE in these two neuropsychiatric disorders. The aim of this project is to characterize biosignatures in ECM and ADE (cell-specific) and plasma (non-cell-specific) and create a molecular profile for LLD and AD.

Methods:Thus, 46 LLD subjects, 25 AD patients and 34 age- and sex-matched healthy elderly controls were recruited. After psychiatric examination, blood was collected and centrifuged to obtain plasma-free platelets. The sample was collected and stored at -80°C. We used the vFC™ Vesicle Flow Cytometry Kit to count and measure the size of the vesicles.

Results:People with LLD had lower levels of ECM and ADE compared to controls. The opposite was demonstrated for ADE in AD patients, with 2 times more ADE than CT and LLD. Next, we evaluated 49 pro-inflammatory cytokines and neurodegenerative protein levels in whole exosomes and plasma samples. When comparing plasma and exosome scores, there was an overlap in the production of 32 proteins. 12 proteins were identified only in the plasma sample and 5 only in the exosomes. Levels of CXCL2, GDNF, NF-light, GFAP, DR3, and IL-4 receptors in exosomes were increased compared to plasma, demonstrating a cell-specific impulse response in exosomes. When overlaying protein scores in exosomes from individuals with LLD and AD, 14 proteins were common to both disorders, 15 were unique to exosomes of LLD, and none of the proteins scored were unique to exosomes from participants with AD.

Conclusions:These preliminary findings underscore the importance of exosomes in cell communication and the common biomarkers shared by LLD and AD. This mechanism may contribute to the crosstalk between brain cells and the periphery as a window to directly assess the molecular pathology of LLD and AD.

Key words:Depression in old age, Alzheimer's disease, extracellular vesicles, inflammatory markers, neurodegeneration

To disclose:Nothing to disclose.

Stephanie Page*, Anthony Ramnauth, Madhavi Tippani, Erik Nelson, Heena Divecha, Elizabeth Pattie, Thomas Hyde, Leonardo Collado Torres, Kristen Maynard, Stephanie Hicks, Keri Martinowich

Lieber Institute for Brain Development, Baltimore, Maryland, EUA.

Background:The three-layered archcortex of the hippocampal formation (hippocampus) exhibits unique patterns of gene expression, morphology, physiology, and connectivity that change during development throughout the lifespan. In rodents and non-human primates, the hippocampus is one of the few brain regions in which neurogenesis has been described throughout life. Due to its structure and circuitry, the region has been implicated in several critical behavioral functions, including the regulation of learning, memory and mood. Hippocampal neurons are organized into densely packed layers based on dendrite-axon polarity, reflecting the intrinsic connectivity of hippocampal circuits. In general, afferent projections to the hippocampus are received in the dentate gyrus (DG), which are then relayed via synaptic relays in the ammonium horn (AC) areas, with the latter efferent projections carrying information from the hippocampus via the hippocampus. subicule ( SUB). 🇧🇷 Synaptic relays in the hippocampus are important sites of structural and functional plasticity throughout life that regulate critical functions related to learning, memory, mood and stress regulation. Many important plasticity-related transcripts are located in the dendritic compartment, and their transcription, transport out of the nucleus, and translation within the dendritic compartment are tightly regulated by both neuronal development and activity. Recent publications have generated cell-type specific molecular profiles of adult and lifelong human hippocampus using single-core RNA sequencing; however, these features lack spatial resolution within the hippocampus and miss transcriptomic information from the cytosolic compartment. Furthermore, despite extensive characterization of the functional significance of postnatal neurogenesis in rodent GD, the indisputable evidence for adult neurogenesis in human GD remains elusive and its lifelong persistence remains controversial. Given the close correlation between spatial structure and function in the hippocampus and the particular importance of transcripts located in the synaptic compartment, molecular profiling technologies with the ability to fill these knowledge gaps would be very useful. Previously, we generated spatial transcriptome maps of the human dorsolateral prefrontal cortex that captured lamellar structure from white matter to the pial surface and included nuclear and cytosolic gene expression. This data has been made publicly available in the form of interactive browsers for the neuroscientific community to query the data (Maynard, Collado-Torres, 2021) and here we describe the generation of a similar feature in the human hippocampus, which also includes the developmental stages from infancy to adulthood. adulthood.

Methods:We used the 10x Genomics Visium Spatial Gene Expression platform, which combines spatially resolved transcriptome profiles with high-resolution histological images, to generate spatial transcriptome maps of the human anterior hippocampus analogous to the rodent ventral hippocampus across the lifespan. To first characterize the organization of the adult hippocampus, we scored tissue blocks and used multiple matrices to fully capture all major subfields (CA1-4, DG and SUB) in adult donors (N = 9 neurotypical donors, both male and female). women, 159,744 places in 32 fishing areas). To study hippocampal development during postnatal life specifically in DG, we simultaneously generated spatially resolved gene expression profiles of the entire transcriptome, focusing on this region of neurotypical donors during human life: child, adolescent, adult and elderly donors (N = 3 donors, 10,503–12,552 points per group, 12 capture areas in total).

Results:We apply unsupervised clustering algorithms with spatial information to all donors to identify gene expression signatures that define spatial domains. We then compared these spatial domains with independently derived and manually labeled annotations of anatomically defined hippocampal subfields, visually guided by histological staining and expression of known marker genes. We compared gene enrichment across spatial domains and identified markers of postnatal development associated with a variety of biological functions, including neurogenesis, plasticity, and apoptosis, among others. To make this data available to the community and to more effectively support studies of hippocampus function, we created an easy-to-use, interactive data exploration web application.

Conclusions:We generated spatially resolved transcriptomic profiles of the adult human hippocampus spanning all major subfields, and in particular within the lifelong DG, which identified canonical and novel patterns of spatial gene expression. Spatial resolution techniques to identify molecular profiles in the context of underlying tissue architecture are particularly important given the close structure-function relationship of cytoarchitecture in the adult and developing hippocampus. This resource provides a rich source of information on spatial gene expression in the hippocampus across the lifespan that can be searched for insights that contribute to understanding the etiology of specific human neurodevelopmental disorders and neurodegenerative diseases in humans. the hippocampus is involved.

Key words:Hippocampus, spatial transcriptomics, dentate gyrus

To disclose:Nothing to disclose.

Gladys Shaw, Molly Hyer, Amy Wegener, Samya Dyer, C. Christina Mehta, Igho Ofotokun, Gretchen Neigh*

Virginia Commonwealth University, Richmond, Virginia, USA. UU.

Background:Mitochondrial dysfunction can lead to changes in neuronal function and behavior and is influenced by aging and early life experiences. In this case, male and female rodents were used to determine the influence of sex, age and adolescent stress on mitochondrial synaptic function and the predictive value of peripheral markers.

Methods:C57Bl/6NTac mice were exposed to repeated chronic predatory stress (CRPS) for 15 days during puberty (PND36-50) and early adulthood (PND57-71). Furthermore, the influence of aging was examined in Wistar rats. In both studies, mitochondrial synaptic respiration was assessed using the SeahorseXFe24 instrument in the hippocampus (HPC) and prefrontal cortex (PFC). Peripheral inflammatory markers, reactive oxygen and mitochondrial function were measured.

Results:History of stress did not alter the rate of oxygen consumption (OCR) of synaptic mitochondria in the PFC of both sexes (p > 0.05). History of stress reduced HPC OCR (p = 0.0045) in men, but increased HPC OCR (p < 0.0001) in women. Regarding the effects of aging on mitochondrial function, age in men altered total OCR in PFC (p<0.0001) and HPC (p<0.0001) synaptic mitochondria. Compared with younger and older men, middle-aged men had basal respiration (p<0.0001), maximal respiration (p=0.0006), proton leakage (p=0.0003), reduced output of ATP (p<0.0001) and reserve capacity (p< 0.0001). p < 0.0001) = 0.005). Western blot densitometry showed that older men had the highest mitochondrial density (p = 0.01). In women, PFC-OCR was increased in middle-aged women compared to younger (p = 0.03) and older (p < 0.0001) women. Middle-aged women had higher baseline breathing (p<0.0001), maximal breathing (p<0.0001), ATP production (p<0.0001) and free capacity (p<0.0001) both in the HPC and in the HPC in the PFC than in the other age groups. Mitochondrial synaptic density was reduced in older women (p = 0.004).

The sample size for the CRPS study was 10 per group for each gender. The sample size for the aging study was 6 per group, sex and age. Test statistics for the results presented above are included here. History of stress reduced HPC OCR (F(1,132) = 8.340, p = 0.0045) in men, but increased HPC OCR (F(1,108) = 17.68, p < 0.0001) in women . Regarding the effects of aging on mitochondrial function in men, age altered the total OCR within the PFC (F(2,180) = 32.96, p < 0.0001) and HPC (F(2,180) synaptic mitochondria. ) = 60 .31, p<0.0001). Compared with younger and older men, middle-aged men had reduced baseline breathing (F(2,30)=13.02; p<0.0001), maximal breathing (F(2,30)= 9.52; p=0.0006), proton leakage (F(2.30)=10.54; p=0.0003), ATP production (F(2.30)=26.63; p< 0.0001 ) and reserve capacity (F(2.30)=6.44; p = 0.005). Western blot densitometry showed that older men had the highest mitochondrial density (F(2,12)=6.85; p=0.01). Middle-aged women had higher basal respiration (F(2,30)=21.63; p<0.0001), maximum respiration (F(2,30)=26.17; p<0.0001), production of ATP (F(2.30)= 20.59; p <0.0001) and free capacity (F(2.30)=29.88; p<0.0001) in HPC and PFC than in other age groups .

Conclusions:Although men and women showed changes in synaptic OCR as a function of early childhood stress and age, the patterns of changes differed by gender. Mitochondrial dynamics in males did not show region-specific differences, however, female dynamics were significantly lower in HPC than in PFC in all dynamic measurements. Ongoing work suggests that estrogen signaling within mitochondria is a key factor in these differences and is reflected in peripheral metrics.

Key words:Mitochondrial respiration, sex differences, synapses, prefrontal cortex, hippocampus

To disclose:Nothing to disclose.

Emily Leptich, Rachel Arey*

Baylor College of Medicine, Houston, Texas, EUA

Background:Cognitive decline is a major deficit that occurs in humans as they age. Although people's life expectancy is increasing, there are currently no treatments to effectively treat or prevent age-related memory loss, resulting in an increasing public health burden. Previous work in mammals and our own work in C. elegans have shown a correlation between maintenance of memory function with age and memory regulatory transcription factor cAMP response element binding protein (CREB) activity. However, CREB is expressed throughout the brain and body; Therefore, the identification of tissue- and cell-type specific activators of CREB would provide promising targets for the development of new therapies targeting age-related memory loss. We recently found that activation of the highly conserved Gαq signaling pathway in a single sensory neuron (AWC) in C. elegans could enhance molecularly conserved CREB-dependent long-term memory (LTM) in young animals and decrease related LTM deficits. age. 🇧🇷 The maintenance of LTM capacity with aging through increased Gαq signaling was found to be due to a cell-independent but cell-specific regulation of CREB activity in "memory center" (AIM) neurons in the worm. We recently discovered that the LTM phenotypes observed due to increased Gαq signaling resulted from increased neuropeptide release by AWC sensory neurons. However, the identity of these memory-enhancing neuropeptides, their downstream signaling pathways, and their role in age-related cognitive decline remain unknown.

Methods:Maintenance of C. elegans: Animals were housed under standard laboratory conditions and fed ad libitum with E. coli strain OP50. Synchronized populations for performance and lifetime tests were generated by standard hypochlorite treatment.

RNAi treatment: Standard RNAi was performed by feeding to achieve gene knockout. Briefly, E. coli expressing HT115 RNAi was fed to C. elegans. To inactivate genes in adulthood, animals at the L4 larval stage were fed RNAi after terminal nervous system differentiation. To achieve selective RNA knockdown in neurons, experiments were performed on a transgenic C. elegans strain (egl-30(js126);LC108 [punc-119::sid-1]) expressing a double-sided RNA transporter. neurons.

Behavioral Tests: Standard positive olfactory association tests were performed. These assays combine odorless butanone with food (E. coli) so that animals form a positive butanone association. Learning and memory were assessed as an exercise-dependent increase in butanone preference as measured by population chemotaxis trials (~100 animals per trial) to obtain a chemotaxis index. Memory performance was calculated using the performance index (Chemotaxis_Index (trained) – Chemotaxis_Index (naive/untrained)). All behavioral tests used 10-15 replicates and performed a one-way or two-way ANOVA followed by post hoc Bonferroni tests.

Lifespan Assays: Standard lifespan assays of C. elegans were performed in the context of RNAi treatment. Three biological replicates of ~100 worms were used for each condition. Data were analyzed by log-rank method (Mantel-Cox) in Kaplan-Meier survival analysis.

Results:We found that genetic manipulations that specifically increase AWC neuron neuropeptide secretion in C. elegans reduce age-related deficits in associative learning and LTM (p < 0.05). Longevity analysis revealed that increased secretion of neuropeptides for AWC has no detectable effect on life expectancy (p > 0.05), suggesting that the observed retention of learning and memory capacity is due to increased neural health.

To identify these health-promoting signals, we generated a list of approximately 40 AWC-expressed neuropeptides using publicly available genomic datasets, many of which play no previously known role in associative behavior or aging. We performed an RNAi-based screen on the worm to determine whether specific neuropeptides are required for enhanced neuropeptide-dependent learning and memory in animals with enhanced Gαq signaling. We have identified new peptide signals including insulin-like peptides (ins) and neuropeptide-like proteins (nlps) that promote associative learning and memory, and in ongoing studies we are investigating other excitatory peptides and their role in regulating CREB activity.

Conclusions:Here we found that increasing the activity and secretion of specific neuropeptides delays age-related deficits in associative learning and memory. The identification of new molecules that regulate CREB in a cell-specific manner will be of great interest, as the effects of increasing CREB activity have memory-enhancing effects in invertebrates and mammals and may represent new therapeutic targets for the treatment of cognitive decline. .

Key words:CREB, aging, neuropeptides

To disclose:Nothing to disclose.

Ashley Keiser*, Tri Dong, Enikö Kramár, Christopher Butler, Siwei Chen, Dina Matheos, Joy Beardwood, Ameer Al-Shammari, Yasaman Alaghband, Vanessa Alizo Vera, Nicole Berchtold, Sharmin Shanur, Agatha Augustynski, Pierre Baldi, Carl Cotman, Marcelo Holz

University of California, Irvine, Irvine, California, USA

Background:The ability to learn, consolidate and recall information is critical to daily life, and this ability begins to decline with normal aging and is greatly exacerbated by Alzheimer's disease (AD). Basic research and clinical studies generally support the benefits of exercise for cognitive function. However, age- and disability-related factors, which can affect individuals throughout life, increasingly limit and reduce participation in physical activity and the associated cognitive benefits. Defining the mechanisms by which exercise leads to lifelong cognitive improvement will have therapeutic benefits for people of all ages and abilities.

Methods:In this study, we use exercise as an approach to unlock new understanding of the molecular mechanisms that enable and drive memory consolidation. We identified and used specific exercise parameters that allow for memory consolidation under sub-threshold inappropriate learning conditions, as well as parameters in which these cognitive benefits are sustained for specific time periods. Specifically, adult male mice underwent 14 days of initial training, received a sedentary latency phase (0-2 weeks) and a brief 2-day phase of reactivation training, followed by 3 minutes of inappropriate subthreshold training on a memory. ) assignment. These parameters were then used to study long-term potentiation (LTP) of the hippocampus using theta burst stimulation in the Schaffer collateral pathway. To begin defining the mechanism responsible for long-term memory formation and maintenance of cognitive benefits, we used an unbiased RNA sequencing approach on dorsal hippocampal tissue collected during memory consolidation 1 hour post-exercise in mice expressing the same parameters training mentioned above. 🇧🇷 To examine the role of an identified ACVR1C target gene, a type 1 receptor for the TGF-β family of signaling molecules, in hippocampus-dependent learning and synaptic plasticity, we used intrahippocampal delivery of AAV1-ACVR1C point mutant constructs that increase or improve the Interrupt and Express function two weeks before the onset of the behavior. Sedentary mice were then trained with a subthreshold (3 min) or standard (10 min) OLM task and memory tested the next day. The same mice from the behavioral studies were used to assess the effects of Acvr1c manipulation on hippocampal LTP.

Given the dysregulation of TGF-β signaling that occurs with age and in AD patients, the next objective was to determine whether increased Acvr1c function regulates long-term memory formation and synaptic plasticity in the aging hippocampus of AD mice. and the deficiencies. to improve. First, we examined whether Acvr1c declines with age. The dorsal hippocampus was preserved between 3 and 20 months. female and male C57BL/6J mice and processed for RT-qPCR. Furthermore, Acvr1c transcripts per million (TPM) values ​​from an RNA-Seq dataset obtained by the MODEL-AD consortium were analyzed at 4, 8 and 12 months. Female and male C57BL/6J and 5xFAD mice. To determine whether improving ACVR1C function in the dorsal hippocampus would improve memory and LTP deficiencies at 18 months. C57BL/6J males and 5xFAD, the above methods were used.

Results:We showed that 14 days of voluntary cycling facilitate hippocampus-dependent memory (one-way ANOVA, Group: (F(6.64) = 8.13, P<0.0001; Tukey test: P<0.001, 14D vs. Sed) and synaptic plasticity (one-way ANOVA, group: (F(6.89) = 22.22, P<0.0001; Tukey test: P<0.0001, 14D vs. Thirst) in adult mice excessively sedentary, effects that can be maintained and recovered - compromised with brief 2-day reintroduction to training after sedentary delay (Behaviour: Tukey test: P < 0.05, LTP: P < 0.0001, 2-day reintroduction vs. SED ) We identified a gene that encodes a type 1 receptor for the TGF-β family of signaling molecules, Acvr1c, as one of the few genes (including Bdnf) that show upregulation in the hippocampus under stress conditions, which increases memory formation of long term term and synaptic plasticity allow to function in adequate conditions of learning in adults, since they are impaired memory s (t(17) = 4.65, P = 0.0 002) and synaptic plasticity (t(18) = 3.512, P = 0.0025). , Overexpression of ACVR1C enables learning under inappropriate training conditions in adults (t(18) = 3.303, P = 0.004) and improves LTP (t(14) = 3.953, P = 0.0014). We found a decrease in Acvr1c levels in the hippocampus with age at C57Bl/6J (t(26) = 2.72, P = 0.01) and 5xFAD in male and female mice (3-way ANOVA, age: (F ( 2.48) = 54.95, P < 0.0001, Tukey test: P < 0.0001 12 months vs 4 months) and show that overexpression of Acvr1c improves memory decline associated with age and AD (18 months C57BL/6J: (t(12) = 2.350, P = 0.036) and synaptic plasticity (18 months C57BL/6J: (t(14) = 3.953, P = 0.001), 18 months 5xFAD: (t(10) = 9.653 , P = 0.001).

Conclusions:Using a new exercise-based approach that allows for memory formation under subthreshold inappropriate training conditions, we identified ACVR1C as a critical driver and bidirectional regulator of memory formation and synaptic plasticity in the adult brain. We also demonstrate a key role for ACVR1C in aging and the AD brain. These data suggest that promotion of ACVR1C through exercise or pharmacological intervention may protect against age-associated cognitive decline and AD and offer a new and potentially effective disease-modifying treatment strategy for AD.

Key words:Memory, Movement, Long-Term Potentiation, Hippocampus, Alzheimer's Disease

To disclose:Nothing to disclose.

Leslie Nucifora*, Christopher Ross, Russell Margolis, Gwenn Smith, Robert Sweet, Frederick Nucifora

Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.

Background:Alzheimer's disease (AD) is the most common neurodegenerative disorder, universally characterized by cognitive impairment and heterogeneously by emotional and behavioral changes. Between 40-60% of patients with AD suffer from psychotic symptoms. Recent studies indicate greater cognitive decline and faster cognitive decline in AD patients with psychosis (AD+P).

Schizophrenia (SCZ) affects 1% of the population and is characterized by positive and negative symptoms and cognitive deficits. Psychosis in the form of hallucinations and delusions is the most noticeable symptom. SCZ is also a heterogeneous disorder in its clinical presentation and progression.

The pathological hallmark of AD is protein aggregation. Protein aggregation likely disrupts important proteins and signaling pathways that can lead to AD symptoms, including psychosis and cognitive decline. We demonstrated protein aggregation in a subset of SCZ patients. Furthermore, using olfactory neurons, we showed that patients with SCZ with aggregation have more pronounced cognitive impairment than patients with SCZ without aggregation as a mechanism. Furthermore, we and others have previously shown that protein products from rare SCZ-associated genetic variants in unique pedigrees can aggregate and alter the function of critical proteins required for proper cell function. While protein aggregation has been linked to neuronal cell death in AD, the protein aggregation we see in SCZ likely leads to cell dysfunction rather than profound cell loss. Although the mechanisms leading to aggregation in both diseases may partially differ, similarities likely exist, with proteins tending to overlap between diseases and being associated with the shared clinical phenotype of psychosis and/or cognitive impairment. Therefore, we hypothesize that there will be proteins and signaling pathways in AD that overlap with some of those identified in patients with SCZ with protein aggregation as a mechanism, thus providing insight into common signaling pathways and mechanisms associated with AD, AS and SCZ .

Methods:A comparative proteomics study of protein mass spectrometry data obtained from biochemically insoluble proteins isolated from Alzheimer's disease, as reported in a previous proteomics study (Hales et al., 2016) and post mortem schizophrenic brains. Proteome Discoverer was used to analyze the proteomic data in order to maximize the number of identified proteins. Panther pathway analysis was used to analyze the enriched protein data to determine the proteins and biological processes most relevant to protein insolubility in AD and SCZ.

Results:We obtained promising preliminary data through a comparative proteomic study of insoluble proteins in an SCZ subtype characterized by protein aggregation with proteins identified in a similar earlier study of proteomic insolubility in AD, suggesting overlap in proteins and signaling pathways between the two neuropsychiatric disorders . These results indicate a common proteomic signature in AD and SCZ.

Conclusions:By comparing the aggregated proteins in AD with the aggregated proteins in SCZ, a disease characterized by psychosis and cognitive deficits, we can better understand the common pathways involved in these disorders.

Key words:Alzheimer's disease, schizophrenia (SCZ), proteomics

To disclose:Nothing to disclose.

Nunzio Pomara*, Chelsea Reichert Plaska, Davide Bruno, Jaime Ramos-Cejudo, Ricardo S. Osorio, Amanda Heslegrave, Anilkumar Pillai, Bruno Imbimbo, Henrik Zetterberg, Kaj Blennow

Nathan S. Kline Institute, New York University, Orangeburg, New York, USA.

Background:Both female sex and depression are associated with an increased risk of Alzheimer's disease (AD), but the mechanisms of the increased risk remain poorly understood. Increased amyloid deposition in the brain and microglial activation have been linked to AD and depression. However, to our knowledge, there are no studies that have examined whether gender- and depression-related effects on amyloid β-peptide (Aβ) dynamics and microglial activation may contribute to an increased risk of female-related AD and depression. Non-amyloidogenic proteolytic cleavage of amyloid precursor protein (APP) by α-secretase results in the release of a secreted form of APP (sAPPα), whereas amyloidogenic cleavage by β-secretase releases a C-terminally truncated form of APP (sAPPβ ) more Aβ. Both sAPPα and sAPPβ have been reported to induce microglial activation. These observations led us to investigate the relationship between gender, depression, and sAPPα and sAPPβ levels in cerebrospinal fluid (CSF). CSF levels of the ectodomain of secreted trigger receptor expressed in myeloid cells 2 (sTREM2), which has been shown to be a specific marker for microglial activation, were also examined. In addition, we also examined the potential influence of APOE genotype on these biomarkers.

Methods:Fifty-one cognitively intact subjects (31 subjects with major depressive disorder and 20 age-matched healthy controls) over age 60 completed a 3-year longitudinal study and optional lumbar puncture. Mann-Whitney U tests for independent samples were used to examine group differences by diagnosis, sex, and APOE genotype for sAPP-α and sAPPβ.

Results:There were no significant differences between subjects with major depressive disorder in later life (LLMD) and controls in mean (± SEM) CSF sAPPα (551 ± 48 vs. 616 ± 50 pg/mL) or sAPPβ (164 ± 15 vs. at 187 ± 14 pg/ml). Regardless of the diagnosis, women had significantly higher values ​​for both sAPPα (p = 0.016) and sAPPβ (p = 0.010) compared to men. sAPPα and sAPPβ were significantly correlated (rho = 0.930, p < 0.001). Mean CSF sTREM2 concentrations were 3507 ± 490 pg/mL in subjects with LLMD and 5096 ± 640 pg/mL in controls (p = 0.075). In the whole sample, sTREM2 was correlated with sAPPα (rho = 0.462, p = 0.001) and sAPPβ (rho = 0.504, p < 0.001). Examining relationships as a function of diagnosis, we found that sAPPα was associated with sTREM2 only in controls (rho = 0.474, p = 0.035), whereas sAPPβ correlated with sTREM2 only in LLMD (rho = 0.370, p = 0.048). Examining the relationship by gender, we found that sTREM2 was associated with both sAPPα (rho = 0.629, p = 0.002) and sAPPβ (rho = 0.673, p = 0.001) in females but not in males (sAPPα: rho = 0.310 ) correlated significantly, p = 0.109; sAPPβ: rho = 0.341, p = 0.076). Finally, based on APOE genotype, significant associations were found only for non-APOEe4 carriers. sTREM2 was correlated with sAPPα (rho = 0.567, p<0.001) and sAPPβ (rho = 0.579, p<0.001) in the e4-negative group, but not for e4-positive (sAPPα: rho = 0.182, p=0.516; sAPPβ: rho = 0.193, p = 0.491).

Conclusions:We found no significant differences in mean CSF sAPPα and sAPPβ levels between controls and LLMD or between APOE-ε4 carriers and non-carriers. We found significant associations of sTREM2 with sAPPα and sAPPβ in women but not in men. sAPPα and sAPPβ were significantly correlated only in non-APOE-ε4 carriers, but not in APOE-ε4 subjects. These observations suggest that APP expression may affect the neuroinflammatory response mainly in women and non-APOE-ε4 carriers and therefore should be explored as a potential molecular therapeutic target for the prevention and treatment of AD in these populations of women.

Key words:CSF sTREM2, sAPPβ, sAPPα, Mikroglia, Depression

To disclose:Nothing to disclose.

Adrienne Grzenda*, Prabha Siddarth, Helen Lavretsky

UCLA, Los Angeles, California, USA

Background:Subjective cognitive impairment (PD) and mild cognitive impairment (MCI) accompanied by cardiovascular risk factors (CVRF) are known risk factors for the development of dementia. Yoga has been identified as a safe practice with positive effects on cognitive function in healthy older adults and older adults at risk of cognitive decline. While yoga generally involves postures (= asanas), focus on the breath (= pranayama), alignment of posture and movement, short meditative practices are also beneficial for brain health and cognition. Kirtan Kriya (KK), a yogic meditation, has been linked to improved mood, cognition, and quality of life in SCD and MCI.

Methods:We conducted a randomized controlled trial to evaluate the effectiveness of kundalini yoga combined with kirtan kriya meditation (YOGA) and memory enhancement training (MET) on mood and cognitive functioning in a group of elderly women with CVRF and SCD (clinicaltrials. gov=NCT03503669) . INTERVENTIONS: The YOGA intervention consisted of weekly 60-minute face-to-face classes with a certified teacher for 12 weeks. In addition, each participant received a CD with a 12-minute guided KK recording for the daily homework exercise. The MET consisted of 12 weekly face-to-face group lessons with daily 12-minute homework assignments. RESULTS: Memory performance was the primary outcome. A delayed retrieval proficiency score was calculated from the Hopkins Verbal Learning Test, the Wechsler Memory Scale, and the Rey-Osterreith 3-Minute Complex Picture Delay Test. An executive functional area score was calculated from the Stroop and Trails B interference tests. Secondary endpoints were depression (BDI, Beck Depression Inventory), anxiety (HAM-A, Beck Anxiety Rating Scale). Hamilton), stress (PSS, Perceived Stress Scale), resilience (CD-RISC, Connor-Davidson Resilience Scale), subjective memory (MFQ, memory function questionnaire, factor 1 = frequency of forgetting, factor 2: severity of forgetting ) and health-related quality of life (SF-36, 36-item short survey). Outcomes were measured at 12 and 24 week follow-up. BIOLOGICAL SAMPLES: Whole peripheral blood samples were collected at baseline, 12 weeks, and 24 weeks follow-up for RNA sequencing and cytokine/chemokine assays. RNA-SEQ: RNA sequencing was performed on 2 lanes of the Illumina NovaSeq 6000 S4 for 2 x 150 cycles in paired-end mode, generating sequencing reads of 150 bp (average of ~30 million reads/sample). Differential gene expression was analyzed using negative binomial generalized linear models (DeSeq2 and edgeR, R 4.1). Cytokine/Chemokine Assay: Human 38-plex magnetic cytokine/chemokine kits (EMD Millipore, HCYTMAG-60K-PX38, Burlington, MA) were used according to the manufacturer's instructions. STATISTICAL ANALYSIS: Results (clinical and cytokine/chemokine concentrations) were analyzed using a general linear mixed-effects model (SAS 9.4) including intervention group, time, and interaction between time and intervention group. Age, sex and education were used as covariates (only for cognitive parameters). Post-hoc analyzes determined the significance of differences between specific peer groups and within-group changes. Effect sizes (Cohen's d) were calculated for clinical outcomes.

Results:CLINICAL RESULTS: A total of 79 participants (YOGA = 40; METs = 39) were randomized and 63 completed the 24-week follow-up (YOGA = 65% completion rate; METs = 95%; χ2(1)=10.9 , p < 0.001). The mean age of the participants was 66.5 (SD = 9.2) years and the mean MMSE was 28.4 (SD = 1.4). After 12 weeks and 24 weeks of follow-up, both interventions showed improvement in the frequency of forgetting (MFQ factor 1). Differences between groups were not significant (F(1, 76)=0.2, p=0.7). After 24 weeks, YOGA participants showed between- and within-group improvements in forgetting severity/MFQ factor 2 (YOGA mean (SD) change = 0.65 (1.25), t (76) = 2.1, p = 0.04, MET mean). Change (SD)=-0.31 (1.35), t(76)=-0.9, p=0.4, F(1, 76)=4.9, p=0.03, size of effect (95% confidence interval)=-0.73 (-1.26, -0.19)). YOGA participants showed a decrease in delayed recall scores between and within groups at 24 weeks (YOGA mean (SD) change = -0.31 (0.37 t(76) = -3.8, p = 0 .0003, MET - Mean change (SD = 0.02 (0.55 ) ), t(76)=0.5, p = 0.6, F(1, 76)=10.3, p = 0.002, effect size (95% confidence interval=0.19 (-0.32, 0.70)), with no difference between or within groups (F(1, 76)=0.8, p=0.4 ) GENE EXPRESSION: Compared with MET, modulated YOGA after 12 and 24 weeks of follow-up targets only interferon signaling and innate and adaptive immunity CYTOKINE/CHYMOKINE LEVELS: Compared with YOGA, MET participants demonstrated higher levels of eotaxin-1 ( F(2.67) =3.94, p = 0.02) after 12 and 24 weeks of follow-up.

Conclusions:After 24 weeks of follow-up, YOGA resulted in a large and significant improvement in effect size on subjective cognitive impairment compared with MET. At the transcriptional level, YOGA is a robust mediator of psychoneuroimmune pathways, including the suppression of several typically pro-inflammatory molecules. Levels of eotaxin-1 increased over time in the MET participants but not in the YOGA participants. Levels of eotaxin-1 have been shown to increase with age and cognitive decline. These results suggest clinical and biological benefits of YOGA on SCD in menopausal women at risk of Alzheimer's disease due to cardiovascular disease, and changes in cognition are associated with yoga's anti-inflammatory effects.

Key words:Clinical trial, cognitive impairment, transcriptomics, neuroimmunology, Alzheimer's disease prevention

To disclose:Nothing to disclose.

Lysianne Beynel*, Lifu Deng, Courtney Crowell, Moritz Dannhauer, Susan Hilbig, Hannah Palmer, Alex Brito, Angel Peterchev, Bruce Luber, Sarah Lisanby, Greg Appelbaum, Simon Davis

National Institute of Mental Health, Bethesda, Maryland, USA.

Background:Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique widely used both in clinical practice and in research due to its ability to modulate neural firing. However, rTMS suffers from moderate potency overall, and improving targeting approaches can greatly enhance the effects of rTMS. While early studies used inaccurate scalp-based coil placement to define the stimulation target, more recent studies rely on fMRI results to target navigated neurons. This is done by having participants run a task and extract maximum activation in a specific region of interest or extract the region with the strongest connectivity score during a task or idle state scan. Although these approaches have improved the efficiency of rTMS, they are based on identifying bivariate relationships between a single source and destination node, even though the brain is composed of aggregations of large networks that communicate in highly multivariate ways. This problem is particularly relevant for targeting rTMS in older adults, as the brain undergoes a variety of large-scale network changes. Therefore, a key challenge is to identify a relevant multivariate network measure that summarizes these complex network dynamics and how they change with age. One such measure is network controllability, which measures the strength of influence of a cortical node on the overall network. Central to this approach is the hypothesis that applying energy (e.g. via rTMS) to nodes with high modal control capability could drive the brain into difficult-to-reach states. We have recently shown that young adult participants benefited most from rTMS when the stimulation site coincided with the node with the highest modal controllability. The current study focused on how controllability changes with age and how these changes might affect the effectiveness of rTMS in elderly populations.

Methods:Imaging data from 52 young adults (23.8 ± 4.8 years, 29 women) and 29 elderly (67.9 ± 5.7 years, 17 women) were used. After imaging (including diffusion-weighted imaging), subjects received active or sham rTMS over the left dorsolateral prefrontal cortex or left parietal cortex for four consecutive visits. DWI data was pre-processed using a standard DWI processing pipeline with FSL and MRtrix software to generate a high-dimensional structural connectome in each participant. The number of white matter flow lines connecting each pair of regions was used to calculate the modal control capability of each node. Modal controllability scores were then compared between the two groups: for the whole brain and for four Yeo Atlas networks. Furthermore, since modal controllability is derived from the DWI data, we calculated degree, the number of links connecting a node, to test whether the results were controllability specific or simply reflected changes in structural connectivity with age.

Results:Results showed significant differences in modal controllability due to aging. In particular, paired-sample t-tests showed that older adults have significantly greater modal control ability for each of the four tested networks (DMN, Fronto-Parietal, Visual and Somoto-Motor) compared to younger adults. (p <0.001 for all comparisons, KIs = [0.009;0.02];[0.01;0.03];[0.01;0.02];[0.02;0.03] for each network ). Young adults showed greater modal control capacity in the medial and parietal prefrontal regions, as expected by network control capacity theory, which states that most of these nodes reside in a cognitive control network. 🇧🇷 However, older adults did not show this pattern and instead had greater modal controllability in the premotor and SFG regions. Finally, the grade analysis showed no significant age-related differences in these areas of interest, providing evidence that the results were specific for controllability.

Conclusions:Taken together, these results suggest that while network controllability can be used as a potential targeting approach for rTMS and has been associated with some promising results, there are some important considerations about the impact of aging on which targets. they must be chosen for maximum impact. Contrary to assumptions based on executive control, modal controllability nodes for older adults were not found in the fronto-parietal network, but rather in sensory and premotor regions. Furthermore, the fact that age differences in controllability are not explained by structural changes in connectivity reinforces the idea that this measure reflects more than just connectivity.

Key words:rTMS, Diffusion Tensor Imaging (DTI), Alterung

To disclose:Nothing to disclose.

Christian Garcia, Ben Lewis, Sara Nixon*

University of Florida, Center for Addiction Research and Education, Gainesville, Florida, USA.

Background:Epidemiological evidence shows that the prevalence of current alcohol use among older adults has increased dramatically over the past two decades. The importance of this change is reinforced by the fact that aging is generally associated with increased susceptibility to the adverse effects of alcohol on various biobehavioral processes, including sleep. In particular, sleep problems are commonly reported even in healthy older adults, regardless of alcohol consumption. Therefore, the intersection between age, alcohol use and sleep constitutes an important area of ​​investigation. Here, we examine the relationships between sleep and alcohol consumption in a sample of healthy community-dwelling older adults, focusing on possible gender differences in these effects. Together, the evolution of alcohol consumption patterns, changes in the age distribution of the population and robust data on the sensitivity and relevance of sleep for well-being reinforce the relevance of this area of ​​study.

Methods:Fifty-six (36 female) healthy adult current drinkers aged between 65 and 90 (M = 74.02 ± 5.86) were recruited to participate in an initial study that investigated the possible effects of psychosocial stressors on alcohol use. . For our current purpose, let's focus on sleep disorders/problems. Composite values ​​for the typical amount (QFI) of absolute alcohol consumed were derived. Participants completed the Pittsburgh Sleep Quality Index (PSQI), a self-report sleep measure that assesses subjective sleep quality with global scores greater than 5, reflecting poor sleep. General linear models were used to assess the relationship between sleep disorders and alcohol use (dependent measure). Sex and its potential interaction with sleep were included in the model. Additional analyzes were also performed using the NIAAA criteria for low risk and heavy drinking.

Results:Significant effects of gender [F(1.108)=6.76, p=.01] and sleep disorders [F(1.108)=16.07, p<.0001] were found. As expected, men approved higher alcohol consumption than women. Contrary to our initial expectations, higher rates of poor sleep predict lower alcohol consumption. However, these effects are put into perspective by a significant interaction between sleep and gender [F(1.108)=4.10, p=0.05]. Interaction research revealed a stronger negative connection between more severe sleep disorders and lower alcohol content in men (r = -0.44, p = 0.004) than in women (r = -0.27, p = 0 .02). There were no gender differences in adherence to low-risk drinking guidelines (p = .11). Higher indicators of sleep disturbance predicted a greater likelihood of meeting proposed low-risk guidelines [F(1,108) = 4.04, p = 0.05], with no sex per sleep interaction. Higher rates of sleep disorders were also positively related to binge drinking [F(1,108)=11.36, p=0.001]. The presence of a significant interaction between gender and sleep quality [F(1,108)=11.55, p=0.001] for excessive alcohol consumption shows a robust negative relationship in men (r=0.45, p=0.003) compared to women (r = 0.15, p = 0.20).

Conclusions:Taken together, our results highlight differences in alcohol consumption associated with sleep quality/disorders and provide convincing evidence that poor sleep may be indicative of lower alcohol consumption and therefore lower likelihood of adherence. Proposed low-risk alcohol consumption limits in healthy community-dwelling elderly are exceeded. In contrast, older adults who exceeded NIAAA scores for low risk and heavy drinking generally reported better sleep. Therefore, while unexpected, these results may reflect unique sociodemographic characteristics in our sample (eg, well-educated, predominantly non-Hispanic white, high income). Furthermore, the observed gender differences are partially consistent with current evidence suggesting stronger associations between drinking and sleep patterns among men overall. Given the dramatic increase in population aging, the increasing prevalence of alcohol use, and frequent reports of severe sleep deficits/disorders among older age groups, the unraveling of drinking patterns and their potential interactions with sleep and other processes Behavioral biologicals remain an important area. for future research. 🇧🇷

Key words:Insomnia, Elderly, Alcohol

To disclose:Nothing to disclose.

Kyoko Konishi*, Sarah Aroner, Anne Remington, Harlyn Aizley, Jill Goldstein

Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts, EUA.

Background:In early middle age, men and women go through different aging processes. In addition to chronological aging, women experience reproductive aging, which leads to deficiencies in sex steroid hormones, including estradiol. In addition to being neuroprotective, estradiol regulates glucose metabolism and mitochondrial function, including the production of oxidative stress. With menopause, glucose metabolism and mitochondrial function decline by 15-20%. Therefore, menopause represents a window of vulnerability in women that can increase susceptibility to neurodegeneration and cognitive decline. Here we evaluated the longitudinal impact of sex-related metabolic and mitochondrial function and reproductive aging on memory performance in early middle age.

Methods:Participants were assessed at three midlife time points: ages 40-50, 45-55, and 55-63 years. 103 participants (48M:55F) aged between 40 and 50 underwent metabolic and memory tests. Aged between 45 and 55 years, as part of a larger cohort study, the same participants underwent a 5-year follow-up assessment of verbal and associative memory, and mitochondrial function was measured using 8-hydroxydeoxyguanosine (8-OHdG ), a measure of oxidation, assesses DNA damage. Finally, in a subsequent 8-year follow-up study, 76 participants (32M:44F) from the largest cohort, now aged 55 to 63 years, completed the same memory tasks to assess midlife memory loss. Generalized estimating equations that take into account age, education, baseline memory performance, and years of follow-up were used to assess associations between metabolic function and memory outcomes. Models were stratified by sex and included an interaction term.

Results:At age 40 to 50 years, there was no significant association between metabolic health and measures of memory in men or women (p > 0.05). However, women with prediabetic/diabetic HbA1c values ​​(>=5.7) at age 40-50 years performed significantly worse on memory tasks 5 years later than women with lower HbA1c values ​​(b = -6.32, p <0.01) and significantly differed from men (p < 0.01). In men, we found no connections between HbA1c levels and memory performance. Examining the effects of menopause, we found that women with higher HbA1c levels who progressed to postmenopause during the follow-up period had worse memory performance 5 years later (b = -1.22, p < 0.01) in compared to women who remained premenopausal. /perimenopause (p = 0.05). Furthermore, especially in women, poor metabolic health (HbA1c) at age 40 to 50 years was also associated with higher levels of oxidative DNA damage (8-OHdG) measured 5 years later (b = 1.04, p = 0.01; men: b = 0.17, p = 0.54). Elevated 8-OHdG levels at age 45-55 years were, in turn, associated with greater decline in verbal memory during the subsequent 8-year follow-up period (b = -1.54, p = 0.01), again specifically in women (b = -4.12, p = 0.02, women vs men: p = 0.05). In women, on the other hand, effects were determined predominantly by those who transitioned from pre/perimenopause to postmenopause during the 8-year follow-up period (b = -5.92, p < 0.0001), compared to with those who passed were postmenopausal at both times.

Conclusions:The results suggest that midlife metabolic health is related to mitochondrial function and has a greater impact on memory performance in women than in men. Furthermore, the results suggest that metabolic health in midlife may influence memory loss in women during the menopausal transition. However, over time, the healthy menopausal brain can compensate, resulting in attenuation of memory loss.

Key words:Memory, gender differences, menopause, oxidative DNA damage, metabolic function

To disclose:Nothing to disclose.

Julie Dumas*, Jenna Makarewicz, Olivia Nop, Isabel May, James Boyd, Alexandra Potter, Alexander Conley, Brian Boyd, Brittany Bosko, Paul Newhouse

University of Vermont Larner School of Medicine, Burlington, Vermont, EUA.

Background:Cognitive changes that occur during menopause have not yet been linked to the risk of pathological aging and Alzheimer's disease (AD) in old age. Understanding neurobiological factors associated with individual differences in menopausal cognition is critical to understanding normal cognitive aging and identifying risk factors for pathological aging in women. We used data from a subset of participants in the Cholinergic Health After MenoPause (CHAMP) trial (clinicaltrials.gov NCT04129060) to examine how blood pressure, cholesterol, and blood glucose affect relationships between brain structure and cognitive function in women in post menopause.

Methods:At screening, all women provided blood samples, measured vital signs, and underwent neuropsychological assessments, including the Repetitive Assessment of Neuropsychological Status Battery (RBANS). On the first day of the largest clinical trial, participants underwent a brain MRI, which obtained both structural and functional scans. Structural MR data were analyzed using FreeSurfer version 7.1.1 to extract volumes from hippocampal subfields as well as limbic regions including the basal forebrain, fornix, hypothalamus, and mamillary body, which were then corrected for intracranial volume. We examined the relationships between brain structure, performance on neuropsychological assessments, and metabolic measures including systolic and diastolic blood pressure, fasting blood glucose and hemoglobin A1C, and HDL and LDL cholesterol.

Results:45 women contributed data to this analysis and were on average 59.3 years old (SD 5.1 years old). All were postmenopausal, clinically healthy, and cognitively normal, as defined by our study's eligibility criteria. Inclusion criteria allowed for medications for controlled hypertension (nine women), hyperlipidemia (four women), and type 2 diabetes (one woman). We examined relationships between variables of interest and then used partial correlations to examine relationships between cognition and brain structure that remained after controlling for metabolic factors. First, age was correlated with systolic blood pressure (r = 0.22, p = 0.03), but not with other metabolic, cognitive or brain volume data. In contrast, metabolic measures that were consistently positively correlated with cognitive performance and brain volume in the limbic regions and hippocampus subfields included systolic blood pressure, hemoglobin A1C, and LDL. We used a partial correlation approach to examine the relationships between neuropsychological performance and brain structure after controlling for metabolic factors. We found consistent relationships between RBANS immediate memory and the volume of brain regions in the limbic areas, including the left mammillary body (r = 0.51, p < 0.001) and left fornix (r = 0.38, p = 0.00 ). 02). 🇧🇷 after verification of systolic blood pressure, hemoglobin and LDL. Relationships were maintained between immediate memory and the body of the right hippocampus (r = 0.52, p < 0.001) and the tail of the right hippocampus (r = 0.48, p < 0.003) after controlling for systolic blood pressure, LDL and hemoglobin A1C. Slightly weaker relationships between delayed memory in the RBANS and some hippocampal subfield measures were also observed when controlling for systolic blood pressure, hemoglobin A1C, and LDL (ps < 0.05).

Conclusions:These data show that controlling for some metabolic variables allowed us to observe relationships between memory performance and limbic and hippocampal volume in cognitively normal healthy postmenopausal women. These relationships were observed at lower levels before metabolic measurements were controlled. We interpret these findings as evidence that there are associations between cognitive performance and brain volume in brain regions relevant to cognitive processes that are strongest after controlling for subclinical metabolic factors. These data have implications for understanding cognition and brain relationships in postmenopausal women and underscore the importance of studying the metabolic processes that influence brain aging. These data also underscore the need for good control of blood pressure, cholesterol, and blood sugar in women as they age.

Key words:Menopause, TRM, Cognition

To disclose:Nothing to disclose.

Hanadi Ajam Oughli*, Beatrix Krause-Sorio, Prabha Siddarth, Michaela Milillo, Lisa Kilpatrick, Linda Ercoli, Katherine Narr, Helen Lavretsky

University of California - Los Angeles, Los Angeles, California, United States

Background:Geriatric depression (GD) is associated with significant medical comorbidity, cognitive decline and brain atrophy, premature mortality, and suboptimal response to treatment. Therefore, more effective treatment is needed to improve mood, cognition and quality of life in GD. Mind-body interventions such as tai chi are promising additional treatments to antidepressants. We tested the effect of three months of tai chi versus health education control on change in gray matter volume (GMV) and whether baseline GMV predicted symptoms and cognitive outcomes differently in the two groups.

Methods:Forty-nine adults over age 60 (38 women, 11 men) with a diagnosis of major depressive disorder and who were being concomitantly treated with antidepressants were randomly assigned to tai chi training (N=26) or health education control ( N=23). 🇧🇷 We conducted clinical scales for depression and anxiety, and participants were assessed with a comprehensive neuropsychological battery at baseline and during follow-up. In addition, participants underwent an MRI at baseline and at follow-up. We used general linear models (GLM) to test time group interactions on these clinical and cognitive scores. Freesurfer version 6.0 was used to process T1-weighted images and perform voxel-by-voxel-by-group-by-time whole-brain GLM in percent change from symmetrized GMV. In addition, we tested for group differences in the relationship between baseline GMV and symptom change. All models included age and gender as covariates.

Results:Groups did not differ in demographics or clinical scores at baseline (p > 0.05) and there were no differences between groups in symptom change from baseline to follow-up (p > 0.11). There were no differences between groups in change in GMV resulting from treatment. Although lower baseline GMV was associated with greater improvements in anxiety across multiple groups in the tai chi group, the health education control group showed no such effects. This pattern was similar for depressive symptoms in a group in the right precuneus.

Conclusions:Three months of tai chi may not be enough to produce clinical improvements and structural brain changes in GD. However, individual GMV can predict improvements in symptoms. Larger studies are needed to examine the long-term effects of tai chi on clinical symptoms and neuroplasticity.

Key words:Alterdepression, Geriatrics, Cognition, Neuroimaging

To disclose:Nothing to disclose.

Sunny Tang*, Yan Cong, Gwenyth Mercep, Mutahira Bhatti, Grace Serpe, Valeria Gromova, Majnu John, Mark Liberman, Liron Sinvani

Feinstein Institute for Medical Research, Glen Oaks, New York, USA.

Background:Up to 50% of hospitalized elderly (over 75 years) have delirium, which is associated with increased morbidity, mortality and resource use, and a 12-fold increased risk of onset of dementia. However, 75% of deliriums go undetected. Few studies have systematically examined speech and language disorders in hospitalized elderly with delirium and, to our knowledge, no previous studies have attempted to objectively quantify these phenomena using computational methods. The objectives of this study were 1) to systematically evaluate and describe speech and language disorders in hospitalized elderly with and without delirium, 2) to assess whether automated speech analysis is feasible for hospitalized patients with acute illnesses, and 3) to investigate Yes, assisted language and Language features can be used to diagnose delusional patients.

Methods:Hospitalized elderly aged 75 years or older (n = 33) were recruited from three medical units of a teaching hospital. Patients with a documented diagnosis of dementia were excluded. Delirium assessment was performed by trained research assistants and verified by a delusional specialist (LS) and included: guidance, 3-item recall, long-form Confusion Assessment Method (CAM); and Richmond Agitation and Sedation Scale (RASS). The diagnosis was based on these data points and the DSM-5 criteria for delirium. Clinical assessments for speech disorders were performed using the Thinking, Language and Communication (TLC) rating scale. Audio recordings for open-ended tasks, paragraph reading, and speech fluency were collected and then transcribed verbatim. Recordings and transcripts were processed separately for each task, using an automated pipeline to extract acoustic (prosody and voice quality, speech tempo and pauses) and textual (semantic consistency, language influence and errors, lexical features). , parts of speech, number of words in speech) . To limit the feature space, we first selected only those features that showed a trend-level correlation with the total CAM score (p < 0.10) and then visually examined the correlation plots to remove redundancies. The final feature set consisted of 26 measures. Group effects were compared using ANOVA and chi-square tests, correlations were measured using Pearson's coefficients, and category fluency sums were compared with normative data using one-sided t-tests. We used binomial elastic net regression models to predict delusional state (delirium (-) vs. delirium (+)) and trained on the full dataset with 10-fold internal cross-validation.

Results:Of the 33 participants, 10 met the criteria for delirium (Delirium(+)) and 23 did not (Delirium(-)). The delirium (+) group performed significantly better on total TLC (p = 0.05, d = 0.81) and inconsistency (p = 0.001, d = 1.41). Participants with delirium performed worse than participants without delirium in the fluid category (p=0.02, d=-0.97), and both groups performed worse than the normative population (delirium(-): p< 0.001, that is = -1.22; delirium( + ): p < 0.001, d = -2.20). Higher CAM score was correlated with TLC total score (r = 0.41, p = 0.02), inconsistency (r = 0.58, p < 0.001), target miss (r = 0.36, p = 0.04) and lower liquid category (r = -0.41 , p = 0.02). Delusional status was predicted using only demographic data, clinical and language demographic assessments, demographic and computerized speech/language characteristics, or all of these. The model using computer-assisted speech/language and demographic characteristics performed the best, classifying the delusional state with an accuracy of 78%, a kappa of 0.4, and an area under the curve of 0.90. All 23 Delirium(-) participants were identified correctly, in addition to 8/10 Delirium(+) participants. In this model, the presence of delusions was most strongly predicted by language errors in paragraph reading, transcribed symbols (including punctuation, restarts, and incomplete words) in open-ended narratives, use of determinants in the familiar narrative task, and semantic diversity. (lexical ambiguity) of the words given during language competence tasks. The absence of delusions was most strongly predicted by complete pauses during the familiar narrative task (e.g., "uh", "uh"), use of adverbs in open-ended narratives, use of adjectives during image description, and variation in tremors (fluctuations ) in voice amplitude) in speech fluency tasks.

Conclusions:Elderly people hospitalized with delirium have significant speech and language deficits. Delirium is specifically associated with incoherence, loss of purpose, and decreased category fluency scores. Hospitalized older adults without delirium may also have subtle cognitive impairment compared to the normal population, as reflected by lower scores in the fluency categories. Automated speech and language analysis was feasibly performed in critical care and the computer resources were very informative in predicting the delusional state and provided proof of concept for this approach.

Key words:Delirium, older adults, natural language processing (NLP), cognitive impairment, automated natural language analysis

Disclosures: Winterlight Labs: consultants, contract research (own); North Shore Therapeutics: Board Member, Founder (Self)

Lea Zillich*, Metin Cetin, Elisabeth M. Hummel, Gabriel R. Fries, Joseph Frank, Fabian Streit, Jerome C. Foo, Marion M. Friske, Georgy Bakalkin, Anita C. Hansson, Rainer Spanagel, Greg Sutherland, Consuelo Walss- Low, Dirk A. Moser, Marcella Rietschel, Stephanie H. Witt

Central Institute of Mental Health, Mannheim School of Medicine, University of Heidelberg, Mannheim, Germany

Background:Alcohol use disorder (AUD) is associated with increased mortality and a variety of illnesses, including neurodegenerative diseases and cancer. Biological aging describes the gradual deterioration of biological functions, while chronological age describes the time elapsed since birth. Accelerated biological aging could provide an explanation for the increased mortality and morbidity in the AUD. There are several biomarkers for estimating biological aging (BioAge markers), such as epigenetic clocks, telomere length (TL) and mitochondrial DNA copy number (mtDNAcn), which are also used as markers of inflammation. Epigenetic clocks estimate various age-related phenotypes, such as chronological age (Horvath), biological age (Levine), and telomere length based on the level of DNA methylation. Acceleration of aging can be calculated by reducing chronological age to epigenetic age and analyzing the residuals. To date, no analysis has examined multiple BioAge markers associated with AUD in peripheral blood, and it is unclear how they are associated with AUD in other tissues. While AUD has effects throughout the body, addiction is believed to occur in the brain. Recent studies point to changes in DNA methylation and gene expression in neuroinflammatory pathways in the brain that may be related to biological aging mechanisms. TL naturally decreases with age, although the effect on the brain is much less than on whole blood leukocytes because there are fewer cells to differentiate/mature. At the same time, increased neuroinflammation in the AUD may lead to a reduction in telomere length and altered mtDNAcn (and heteroplasmy). Biological aging is believed to be accelerated in AUD and this effect is more pronounced in whole blood than in brain samples.

Methods:BioAge markers were measured in two cohorts of subjects with AUD and controls. The first cohort consisted of 179 subjects, 84 of whom were diagnosed with AUD, from whom whole blood samples were collected at the start of withdrawal treatment. The second cohort consisted of postmortem human brain samples. Brain tissue was obtained from the New South Wales Brain Tissue Resource Center at the University of Sydney. A total of 91 samples from Brodmann's area 9 (N cases = 43), 94 from the caudate nucleus (N cases = 44) and 63 from the ventral striatum (N cases = 33) were included in the present analysis.

For both cohorts, telomere length and mtDNAcn were measured by quantitative real-time polymerase chain reactions (qRT-PCR) and methylation levels were analyzed with the Illumina Infinium EPIC BeadChip. Levine, Horvath and telomere epigenetic clocks were calculated using the Methylclock R-package. For the Levine and Horvath watches, acceleration of aging controlled by cell type composition was used as the output, while the crude estimate of the estimated telomere length was used to ensure comparability with the measured LT. We performed linear regression analysis with BioAge markers as outcomes and included sex, AUD status, an interaction term AUD status*age, smoking status, and age (for measured and estimated TL and mtDNAcn) as covariates. To examine the association between BioAge markers, we calculated Pearson's correlation between markers in each sample.

Results:In peripheral blood, we identified significant associations between BioAge markers and AUD status, all pointing to accelerated biological aging in AUD. All BioAge markers were associated with chronological age in the expected directions, and small to moderate correlations were observed between BioAge markers. The highest correlation was observed for measured and estimated telomere length with r = 0.26.

In postmortem human brain samples, a significant association of measured TL and AUD (p = 0.047) and a trend towards the AUD*age interaction (p = 0.061) was observed in the caudate nucleus. Only low correlations between BioAge markers were observed in postmortem brain samples.

Conclusions:The present study is the first to examine telomere length, epigenetic clocks, and mtDNAcn from whole blood and postmortem brain samples in subjects with AUD compared to healthy controls. We found evidence of increased biological aging in AUD, as evidenced by significant associations between epigenetic acceleration of aging, decreased telomere length, and decreased mtDNAcn with AUD in whole blood. The study of biological aging in AUD seems to be more appropriate in blood samples. The present study cannot distinguish whether there is no AUD-related increase in biological age in the brain or whether BioAge markers do not capture age acceleration equally well in brain tissue. Levine and Horvath's epigenetic clocks are designed as multi-tissue biomarkers and therefore should work similarly in brain tissue. Although the telomere clock was trained on DNA methylation in the blood, we observed little association between estimated and measured telomere lengths in the present study. More studies examining the brain and blood tissues of the same individual are needed to draw conclusions about the overlapping molecular mechanisms of biological aging in the blood and brain.

Key words:Biological aging, alcohol use disorder, telomere length, mitochondrial DNA copy number, epigenetic clock

To disclose:Nothing to disclose.

Paul Newhouse*, Alexander Conley, Tonnar Castellano, Brian Boyd, J. Patrick Begnoche, Sepideh Shokouhi, Brittany Bosko, Julie Dumas

Vanderbilt University Medical Center, Nashville, Tennessee, EUA.

Background:Women appear to be at greater risk of Alzheimer's disease. This increased risk may be related to the loss of estradiol (E2) support for the basal forebrain cholinergic systems. The cholinergic system has been implicated in many aspects of the cognitive effects shown after E2 administration, including attention, working memory, and strenuous tasks such as verbal memory. The Cognitive Health After MenoPause Study (CHAMP, NCT04129060) examines cholinergic functional integrity in normal postmenopausal women by assessing working memory performance, functional brain activation, basal forebrain cholinergic structure, and uptake of the cholinergic PET radiopharmaceutical [18F]-fluoroethoxybenzovesamicol ([18F]-FEOBV ) and whether there are individual differences in AD biomarkers, including amyloid fluid and tau markers (plasma, CSF), PET scan amyloid and neurodegeneration markers (nFL), with cognition, activation brain after anticholinergic stress, cholinergic anatomy and functional integrity.

Methods:One hundred and twenty cognitively normal and healthy postmenopausal women aged 50 to 70 years will undergo a multimodal assessment that includes measures of sleep and activity, cognitive performance, blood/plasma for AD and genetic biomarkers, and a lumbar puncture for AD biomarkers. LCR. In addition, participants will undergo MRI during anticholinergic (mecamylamine) challenge to assess brain activity related to working memory, as well as the cholinergic structure/volume of the basal forebrain. Participants underwent a 30-minute static PET scan three hours after injection with 6.5 MCi ± 10% [18F]-FEOBV. The T1-MRI white matter mask was superimposed on the [18F]-FEOBV-PET as the reference region for calculating standardized uptake value ratios (SUVR) in the GM composite global ROI (parietal, frontal, temporal, occipital, cingulate, hippocampal) as applied, as well as within individual ROIs. Basal forebrain volumes (BFB) for each hemisphere were extracted from T1-MRI for subregions Ch1-3 and Meynert's nucleus basalis (NBM; Ch4). We examined how regional and whole-brain [18F]FEOBV PET uptake correlated with age, Repeatable Battery for Assessment of Neuropsychological Status (RBANS), cognitive performance, and florbetapir amyloid PET.

Results:Preliminary data show that ten healthy postmenopausal women (mean age: 57.3 ± 5.1 years) have completed cholinergic PET to date. It was observed that overall SUVR decreased with increasing age (r = -0.52, p < 0.1). Greater cholinergic NBM GM volume for both hemispheres (LH: r = 0.51, RH: r = 0.65, p = 0.06) was associated with greater overall [18F]-FEOBV-SUVR. Global [18F]-FEOBV uptake was positively associated with global cognition as measured by the RBANS total score (r = 0.41). Finally, [18F]-FEOBV uptake was lower in participants who had clinically elevated levels of amyloid on the florbetapir PET scan. Evaluation of the relationship of cholinergic integrity via [18F]-FEOBV, BFB volume, and cholinergic functional imaging with reproductive and menopausal history and AD biomarker data continues.

Conclusions:Decreased cholinergic integrity after menopause may increase the risk of future cognitive decline, and [18F]-FEOBV, along with AD-related biomarkers, may be a useful marker of future cholinergic decline. Relationships between cholinergic health and other predictors in this pilot sample support the hypothesis of a menopausal increase in the risk of AD-related pathologies in some women, which may be accelerated by the loss of cholinergic tone due to estradiol deficiency after entering pregnancy. menopause.

Key words:Acetylcholine, women's health, Alzheimer's disease, positron emission tomography

To disclose:Nothing to disclose.

Katie Watson Lin, Fahim Abbasi, Thalia Robakis, Alison Myoraku, Isaac Satz, Natalie Rasgon*

Stanford University School of Medicine, Palo Alto, California, USA

Background:Insulin resistance is an early sign of a metabolic disorder with the potential to cause long-term neuropsychiatric sequelae. The first adverse effects of IR on brain function were demonstrated by direct and indirect measurements of IR. However, the course of pathological brain aging and its mediators and moderators are not precisely defined. To determine whether insulin resistance is associated with preclinical signs of neuropsychiatric impairment in healthy young and middle-aged adults, we recruited 126 overweight people without diabetes or depression who completed an insulin suppression test, a measure direct effect of insulin resistance. resistance, as a battery of neuropsychiatric and cognitive measures. We describe the study design and cohort, and the relationships between baseline metabolic function and cognitive and psychiatric outcomes, including subtle cognitive changes as measured by neuropsychiatric tests and subclinical mood symptoms.

Methods:Participants were recruited through flyers distributed on campus and in communities around Stanford University. Potential participants were assessed based on the following eligibility criteria: age 23 to 61 years, body mass index (BMI) 21 to 41 kg/m2, at least 12 years of education, and score on the Mini Mental State Examination (MMSE). 27, and adequate visual and auditory acuity for cognitive tests. Insulin-mediated glucose uptake was directly measured by a modified and validated version of the insulin suppression test (IST). Insulin and plasma glucose concentration values ​​were calculated in the last 30 minutes of the infusion to determine steady-state plasma glucose (SSPG) and steady-state plasma insulin (SSPI) concentrations, respectively. Plasma insulin, leptin, and cortisol were measured at the Central Clinical Trials Laboratory at the University of Washington School of Medicine. Average relative telomere length was measured by quantitative PCR using a method derived from the method originally published by Cawthon et al. and expressed as the ratio of telomere frequency versus the frequency of a single copy of the gene (human b-globin) (T/S ratios). Depressive symptoms were assessed using the 24-item Hamilton Depression Rating Scale (HDRS). A cognitive battery of four hippocampus-related tests was used on all participants in a fixed or randomized order.

Results:Insulin resistance was associated with poor performance on a visuomotor task (Purdue pegboard) and increased subclinical symptoms of depression. Furthermore, direct measurement of insulin resistance (SSPG concentration), but not fasting plasma insulin, fasting plasma glucose, or BMI, was associated with higher levels of depressive symptoms in subjects without clinical depression. Only the association of SSPG concentration with depressive symptoms passed the multiple correction test. The association of SSPG concentration with depressive symptoms was strong after adjusting for age, education, BMI, and fasting blood glucose. Telomere length, obtained as a measure of chronic physiological stress or allostatic stress, showed weak negative correlations with SSPG and fasting blood glucose and stronger negative correlations with age and dyslipidemia.

Conclusions:This study in young and middle-aged adults examines premorbid changes in metabolic function, mood, and cognition that may predict the development of overt psychiatric illness or cognitive decline. We found that even in this population of healthy but overweight young adults, there is a range of insulin sensitivities characterized by higher degrees of insulin resistance associated with higher BMI, hypertriglyceridemia, low HDL cholesterol and high circulating insulin levels. fasting, C-peptide and leptin. Furthermore, higher RI scores were associated with higher degrees of subclinical depressive symptoms and worse performance, particularly on a visuomotor task, but not on cognitive assessments in general. Furthermore, the importance of the association between IR and visuomotor performance and subclinical depressive symptoms was attenuated when BMI and fasting blood glucose were included in the model, suggesting an etiological overlap between these factors. We hypothesize that the cognitive and psychiatric impairments associated with IR are likely to have a prolonged subclinical prodrome, many years before the apparent impairment. These data provide a baseline for testing this hypothesis in future analyses.

Key words:Insulin resistance, telomeres, cognitive impairment

To disclose:Nothing to disclose.

Barry Setlow*, Sabrina Zequeira, Emely Gazarov, Alara Guvenli, Erin Berthold, Takato Hiranita, Lance McMahon, Abhisheak Sharma, Christopher McCurdy, Jennifer Bizon

University of Florida, Gainesville, Florida, USA

Background:Those aged 65 and over have become the fastest growing demographic of cannabis users. With the number of older adults in the US expected to reach 90 million by 2050, it is imperative to understand the potential cognitive impact of cannabis/cannabinoid use in this age group. Cannabis and cannabinoids such as delta-9-tetrahydrocannabinol (THC, the main psychoactive compound in cannabis) generally tend to impair cognitive performance, but almost all studies on cannabis and cannabinoids have been conducted in young adults. As many older adults already have cognitive deficits, it is important to determine how cannabis/cannabinoids affect cognition in this population.

Methods:To address this issue, we examined the effects of chronic oral self-administration of THC on the performance of a working memory task in rats. Fischer 344 x Brown Norway F1 hybrid young (5 months, n=20) and old (23 months, n=18) adult (23 months, n=18) adult (23 months, n=18) rats of both sexes were trained in operant chambers with a memory task critically delayed response-response workload. cortex. In this task, rats were trained in daily sessions of 60 min (over 100 trials/day) to memorize the left/right position of a reaction lever in short delays (0-24 s) to receive food rewards. After achieving stable performance on the task, the rats were given access to plain gelatin or 1.0 mg/kg of THC gelatin for 60 minutes daily in their home cage in the afternoon for 3 weeks, while testing on the working memory task continued for the next 3 weeks. morning. In a second experiment, elderly naughty rats were given plain gelatin or gelatin with 1.0 mg/kg of THC daily in their cage and blood samples were collected after 3 weeks to analyze circulating inflammatory factors. Behavioral data were analyzed by multivariate ANOVA using drug status, age, and gender as between-subject variables and working memory delay as a between-subject variable. Cytokine data were analyzed using the Welch t-test.

Results:As expected, among rats that consumed plain gelatin (control), older rats performed worse than younger rats on the working memory task (F(1,30)=10.38, p=0.003) . More importantly, there was an interaction between age x drug status x delay, such that THC had differential effects in young adult rats compared to older rats, particularly in long delays (F(6,180) = 2.45, p = 0.03). Focused comparisons of the effects of THC in each age group showed that, in young adults, rats consuming THC-gelatin had comparable performance to rats consuming plain gelatin (with no significant effects or drug interactions). In contrast, aged rats consuming THC-containing gelatin performed significantly better than rats consuming normal gelatin (F(1,14)=5.01, p = 0.04), particularly for long delays in feeding. retention (F(6.84)=2.76, p=0.02). There were no sex differences in the effects of THC use in young or old adult rats (no interactions between sex and drug status). In the second experiment, rats that consumed THC jelly for 3 weeks had reduced levels of some pro-inflammatory cytokines (eg TNFα, t(19.99 = 16.61, p<<0.001) and increased levels of some cytokines anti-inflammatory drugs (eg, IL-10, t(19.99) = 6.55, p<0.001).

Conclusions:These results suggest that chronic cannabis/cannabinoid use may have beneficial effects on at least one aspect of executive function (working memory) in older adults. Furthermore, oral administration (which is commonly used by older adults) and the fact that consumption is voluntary suggest that the dose of THC used here is within a tolerable range that does not produce significant side effects. Finally, as changes in the peripheral inflammatory environment have been associated with age-related cognitive decline, the fact that chronic THC appears to attenuate some aspects of inflammatory signaling suggests a mechanism by which it may have beneficial effects on working memory.

Key words:cannabis, aging, working memory, mouse, THC

To disclose:Nothing to disclose.

Tyler Cox, Cobb Karinne, Patel Kesha, Murphy Caitlyn, Horovitz David, Moats Jacqueline, Dufala Haley, Enos Reilly, Hollis Fiona, Joseph McQuail*

University of South Carolina, Columbia, South Carolina, USA. UU.

Background:Women tend to live longer than men and are more likely to be affected by Alzheimer's disease (AD). Indeed, the influence of biological sex and sex hormones is the focus of ongoing studies to determine the mechanisms that contribute to poorer than expected cognitive outcomes in older women and to identify appropriate interventions to protect cognition. ways. The ketogenic diet has emerged as a potential intervention to treat the central and peripheral signs of AD, including impaired brain glucose metabolism and elevated resting blood sugar levels. However, it is unclear to what extent older men and women typically experience the same cognitive benefits of the ketogenic diet and whether the age-related declines in circulating estrogens typical of menopause interact with the effects of this diet. Thus, we examined the effects of a ketogenic diet on cognition in normal aging male and female rats (Study 1) or the effects of diet in a surgical model of menopause with and without hormone replacement (Study 2).

Methods:In Study 1, 6 or 24 month old male and female Fisher 344/Brown Norway F1 hybrid rats were obtained from the National Institute on Aging. Rats were instructed to consume sex- and calorie-adjusted diets that provided the majority of calories from carbohydrates (control diet) or medium-chain triglycerides (ketogenic diet). A subset of rats was included as ad libitum-fed controls with unrestricted access to normal chow to distinguish the effects of caloric restriction on diet composition. (n = 7-10/gender/age/diet). After 6 weeks on the diet, during which body weight and blood glucose and β-hydroxybutyrate levels were continuously monitored to confirm nutritional status, all rats were characterized in the Morris Water Maze (MWM) using a memory protocol 8-Day Spatial Location Learning Reference Guide . for the assessment of hippocampus-dependent cognition. For Study 2, 18-month-old female rats were ovariectomized (OVX) and subcutaneously implanted with estrogen-releasing Silastic implants (E2) or inert vehicle (OIL) before being assigned to specialized diets (n=10-12/hormone/ diet ). 🇧🇷 were ) and behavioral tests as described in Study 1.

Results:In Study 1, sex, age, and diet significantly affected spatial memory; Men performed better than women overall, older adults performed worse than younger ones, and calorie restriction and ketogenic diets improved memory compared to ad libitum controls. There was also a trend towards an interaction between gender, age and diet. Follow-up comparisons showed that younger men had better spatial memory after calorie restriction, but in older men only the ketogenic diet improved memory compared with ad libitum-fed controls. In women, calorie restriction improved spatial memory, but only younger women, not older women, had better memory after consuming a ketogenic diet. Loss of benefit from consuming a ketogenic diet may be related to changes in circulating E2, as we found in Study 2 that replacing E2 in middle-aged rats after OVX resulted in diet-induced memory enhancement. obviously not controls. Furthermore, supplementation of E2 to animals consuming the calorie-adjusted control diet did not improve performance compared to OIL.

Conclusions:We conclude that dietary interventions, including calorie restriction and keto, are practical and effective interventions that protect against age-related cognitive decline. However, the effectiveness of certain memory-preserving diets varies between men and women over a lifetime. Older women do not experience the same cognitive benefits of the ketogenic diet that have been seen in younger women or older men. The beneficial effects of the ketogenic diet in older women can be observed after E2 administration, suggesting that this diet may confer cognitive benefits associated with HRT initiated near the onset of menopause in middle-aged women. Overall, this finding can be used to optimize and customize dietary guidelines for subpopulations of older adults at risk for memory loss and AD.

Key words:Ketogenic diet, Declarative memory, Gender differences, Brain aging, Alzheimer's disease

To disclose:Nothing to disclose.

Vinay Parikh*, Alyssa Kniffin, Charlotte Bavley, Miranda Targum, Joanna Severino, James Flowers, Debra Bangasser, Mathieu Wimmer

Temple University, Philadelphia, Pennsylvania, USA

Background:Synaptic release of the neurotransmitter acetylcholine (ACh) has been associated with neuromodulation of cognitive ability. Our previous research has shown that a reduction in ACh transmission in cortical networks increases cognitive vulnerability with age. However, the mechanisms that regulate age-related changes in cholinergic transmission and individual differences in cognitive aging remain unknown. Acetylcholinesterase (AChE) is a hydrolytic enzyme that promotes ultra-fast cholinergic signaling in brain circuits. Here we try to identify the role of synaptic (AChE-S) and reading (AChE-R) variants in AChE regulation and cognition in aging. These variants are reported to be altered in age-related neuropathologies. As exposure to stress has been shown to alter AChE expression and psychological stress is a risk factor for age-related cognitive decline, we also examined the effects of variable chronic stress (SV) on AChE expression and catalytic activity.

Methods:Young (3 months) and old (22 months) rats of both sexes were trained in an operant attention task in which the animals must distinguish between signaled and unsigned cues for subsequent reward. After achieving the performance criteria, the mice were subjected to a distraction test session, after which brain tissue from the prefrontal cortex (PFC) and hippocampus (HPC) was microdissected for AChE mRNA and protein isolation. . The influence of SV on AChE biochemistry was examined in another cohort of adult male and female rats. For these studies, AChE activity was evaluated in saline and detergent-soluble fractions containing different proportions of monomeric (G1) subunits encoding AChE-R and tetrameric (G4) subunits encoding AChE-S, respectively.

Results:In general, old rats performed poorly in the distractor test session compared to young rats (F(1,28)=15.17; p<0.001). However, their performance remained highly variable, with some animals showing significant impairments (p < 0.001 vs. regardless of age), while others performed on a par with young animals (p < 0.43). Quantification of mRNA expression by RT-qPCR revealed an age-dependent reduction in overall AChE expression in PFCs (p < 0.05), which was mainly driven by the S variant. Interestingly, the mean ratio of R/S variants was greater in both brain regions in older mice (PFC: 1.27 vs. 1.01 in juveniles; HPC: 1.93 vs. 1.02), which is an illustrated transcriptional change. Our stress experiments revealed sex differences with higher AChE activity in subcellular fractions rich in G1 and G4 subunits in PFC females (p < .04). However, SV reduced AChE activity in the detergent-soluble fraction regardless of gender (F(1,19)=30.65; p<0.001). Furthermore, an interaction between gender and SV was observed (F(1,18) > 3.72; p<<0.05) showing higher AChE-R subunits in men and lower AChE-S subunits in women.

Conclusions:The age-related reduction in AChE-S (most prominent synaptic variant) may possibly reflect a neuroadaptive role in maintaining cholinergic function by reducing ACh hydrolysis. This interpretation also corresponds to a reduced catalytic activity in the detergent-soluble fraction, which is richer in the G4 isoform in SV-exposed rats. However, an increase in the AChE-R variant during stress or aging may abolish this protective effect. Taken together, these data suggest that an imbalance in AChE R/S variants may underlie cognitive vulnerability in aging and stress-accelerated cognitive decline. Furthermore, stress-induced compensatory changes in cholinergic signaling and their impact on age-related changes in cognitive processes may differ between sexes.

Key words:Aging, cognition, stress, acetylcholinesterase, splice variants

To disclose:Nothing to disclose.

Holly Hunsberger*, Kameron Kaplan, Lainey Tönnies

The Chicago School of Medicine at Rosalind Franklin University, North Chicago, Illinois, EE. UU.

Background:Neuropsychiatric disorders such as depression and anxiety are seen in 90% of patients with Alzheimer's disease (AD) and are common in patients at risk for AD. Previously, we showed that anxiety predominates at a younger age in APP/PS1-AD female mice and that anxious, amyloid-burdened females progress to dementia more rapidly than males in the human ADNI cohort. We also show that there are sex-specific circuits and brain changes in mice with AD at 6 months of age. Furthermore, patients with early-stage AD often have hyperexcitability throughout the hippocampus, which correlates with memory impairment and eventual disease worsening. Here, our aim was to determine how and when this neural activity is altered in aged and AD mice.

Methods:AAV-syn-GCaMP8f virus was injected and a GRIN lens targeted to the ventral hippocampus was implanted (n = 4–6) in 2- and 6-month-old male and female control mice and APP/PS1 mice. After 3 weeks of recovery, mice were challenged in an open field, lifted and guided through a maze and contextual fear conditioning to assess fear-like behavior and cognition. During each task, we recorded calcium activity using Inscopix software and analysis programs. Data were analyzed using ANOVA, with repeated measures where appropriate. Tukey was used for all post hoc comparisons. The alpha was set at 0.05 for all analyses. Data are expressed as mean +/- SEM.

Results:We found gender-specific changes in neural activity and behavior. As previously reported, women showed anxiety and cognitive decline earlier (p < 0.05). Male AD mice did not show anxiety-like behaviors compared to controls when performing these tasks. However, in the elevated plus maze, male AD mice showed changes in neuronal activity as a function of time of day compared to controls (p < 0.001). Furthermore, this increase in calcium transients was correlated with increased behavioral anxiety in men (p < 0.05). We are actively continuing these experiments to add a 6-month age cohort to determine how aging affects neuronal excitation/inhibition balance.

Conclusions:Men and women diagnosed with AD develop cognitive decline, but the mechanisms that lead to this decline may be different. Therefore, it is important to understand the differences in disease progression in order to develop personalized therapies. Our initial studies provided a snapshot of sex-specific mood and circuitry changes throughout the brain, but with our in vivo calcium imaging system, we can now see dynamic changes in the brain as the animal ages and individual cell activities. through the following different behavioral paradigms. 🇧🇷 These results demonstrate that cerebral hyperexcitability begins earlier in men, while women show more behavioral changes at the onset of the disease.

Key words:Alzheimer's disease, anxiety, gender differences, in vivo calcium imaging, hippocampus

To disclose:Nothing to disclose.

Luis Rosas-Vidal*, Saptarnab Naskar, Megan Altemuse, Sachin Patel

Northwestern University, Chicago, Illinois, USA. UU.

Background:Post-traumatic stress disorder (PTSD) is a psychiatric disorder that develops after exposure to a traumatic event. Lifetime prevalence is estimated at 6.8%. Fear responses to stimuli previously present during a traumatic experience allow for survival. However, with PTSD, patients may experience a generalization of their anxiety responses even to safe stimuli. The endocannabinoid system (eCB) is a retrograde neurotransmitter system involved in the regulation of anxiety and anxiety. One of the most important centrally active eCB lipids, 2-arachidonoylglycerol (2-AG), is thought to mediate resilience to traumatic experiences. Here we intend to investigate whether 2-AG is involved in the regulation of fear generation and to characterize how prelimbic neurons are involved in fear discrimination and how 2-AG mediates this process.

Methods:We used a fear conditioning model in mice in combination with systemic injections of a drug (DO34) that blocks 2-AG synthesis. Male mice were subjected to 8-tone (CS+) presentations, each ending with a brief electrical shock to the feet. The next day (day 2), mice were injected intraperitoneally with DO34 (50 mg/kg) 2 hours before a memory test, which was performed by subjecting mice to alternating presentations of 2 new tones (NT) and 2 CS+ tones . 🇧🇷 Anxiety responses were measured by quantifying the percentage of time during the sound presentations that the mice exhibited freezing (immobility, except for the movement required for breathing). For our in vivo recording experiments, mice were injected with a viral vector expressing the calcium reporter GCaMP7f in the prelimbic cortex (PL) and a miniature GRIN lens in the PL. The mice were allowed to recover and become accustomed to having a miniaturized microscope attached to a baseplate that sat on top of the lens. After habituation, mice were conditioned to sounds as described above while simultaneously recording calcium activity using the miniaturized microscope. The following day, mice were injected with vehicle or DO34 and challenged with NT and CS+ tones as described above. The recorded image data was processed and individual calcium traces were extracted using the CNMFe segmentation algorithm. Peritoneal histograms were generated from the z-weighted data. Neurons with post-discharge responses greater than ±3 Z-scores at 2 consecutive 1-second intervals during the 10-second post-discharge period were considered to have significant excitatory or inhibitory responses (+) response or (-) reaction). SVM decoder analysis was performed on traces extracted from events to assess whether NT and CS+ were decodable from each other.

Results:To investigate whether 2-AG is involved in the regulation of fear generation, mice were injected with DO34 prior to fear recall (n = 19 and 16, vehicle and DO34, respectively). Mice injected with DO34 showed a significant increase in freezing only on new sound presentations (all p < 0.0338), but not on CS + , suggesting that blocking 2-AG signaling increases fear generalization, amplified new tones.

To examine how fear generalization is represented at the neuronal level and how this representation is modified by reductions in 2-AG, we repeated our fear conditioning experiment while recording changes in calcium activity of individual cells within PL. Our imaging data show that DO34 increases mean neuronal activity to new sounds (n = 636 and 670 neurons, vehicle and DO34, respectively). Focusing on neurons that significantly alter their tone activity did not show size differences between groups for the (+) response (n = 114 and 204 neurons, vehicle and DO34, respectively). Interestingly, the proportion of neurons that responded to CS+ and new tones was significantly higher in the DO34 group (10.62% vs. 18.36%; chi-square statistic = 7.3072, p = 0.00687). while the proportion of neurons that responded to CS+ was significantly higher, it was lower (32.23% vs. 20.82%; chi-square statistic = 12.771, p = 0.000352). Thus, leading reduction in 2-AG signaling results in greater generalization, and this, in turn, is associated with a greater proportion of PL neurons that are similarly connected to CS +  and signal new tones. We hypothesize that the increase in fear generalization is due to a loss of ability to distinguish between NT and CS +  by PL neurons. Surprisingly, using an SVM decoder, he found that NT and CS +  can be decoded by either of the others, and indeed, the decoder accuracy decreases in the OD34-a group (96.0% for Veh, 99.5% OD34 , 43 0.3% mixed control; all p < 0.0002).

Conclusions:Our current data suggest that 2-AG signaling may be required to maintain the specificity of fear memories. Furthermore, 2-AG reduction leads to a greater proportion of PL neurons that cannot distinguish between CS+ and new tones. Interestingly, although the proportion of PL neurons responding to both tones is increasing, the encoding properties of NT and CS +  are so different that they can decode each other. Therefore, while the fraction of neurons responding to the PL tone reflects generalization/discrimination, the properties of neuronal responses to NT and CS +  are mutually decodable and independent of the generalization state. All of this might suggest that the generalization might be driven by inputs to PL that are sensitive to 2-AG starvation states, rather than arising in the PL itself.

Key words:Fear conditioning, prelimbic, miniscope, in vivo calcium imaging, endocannabinoids

To disclose:Nothing to disclose.

Stephen Walterhouse, Devki Bhatt, Michael Meyerink, Ritchy Hodebourg, Anna Kruyer, Michael Scofield, Peter Kalivas, Lindsay McDonald, Constanza García-Keller*

Wisconsin College of Medicine, Milwaukee, Wisconsin, USA

Background:Converging epidemiological studies indicate that a history of acute life-threatening events increases the incidence of post-traumatic stress disorder (PTSD) and a diagnosis of PTSD is associated with 30-50% comorbid substance use disorders (SUDs) . Therefore, patients with comorbid PTSD/DSD exhibit greater severity of drug use and worse treatment outcomes than patients diagnosed with both alone. Using a rodent model, we found that a single stressful event experienced 3 weeks earlier can enhance drug absorption and induce a series of long-lasting adaptations in the corticostriatal synapses of the nucleus accumbens (NAcore) that resemble drug-induced adaptations. We have recently discovered that combining the stressful event with a new odor (stress-related stimulus, stress-CS) induces a conditioned stress response and recapitulates some of the behavioral and physiological aspects of PTSD. Previous publications have shown that the presentation of drug-associated signals induces a transient increase in five-part synapses, including presynaptic and postsynaptic neurons, astrocytes, microglia, and the extracellular matrix (ECM). Given the overlap between sustained adaptations triggered by acute restraint stress and withdrawal from drug use, we hypothesize that exposure to a CS stress induces synaptic plasticity at the five-part synapse in NAcore. Furthermore, the middle spinal neurons (MSNs) make up 90 to 95% of the neurons in the NAcore and are chemically encoded into two subtypes that selectively express dopamine D1 or D2 receptors. These two populations appear to serve different behavioral functions, with D1 activation generally promoting behaviors and D2 activation inhibiting behaviors. However, the effect on CS stress exposure in the cum population remains elusive.

Methods:Male and female Sprague-Dawley and Long Evan rats were immobilized in Plexiglas cylinders for 2 hours and exposed to an odor that was converted to CS stress, or simulated animals were placed in new cages exposed to an odor (neutral stimulus - NS). expose. Three weeks after the stress experience, the animals were exposed to a cage containing garbage in one corner and Stress CS or NS (noxious object to be buried) in the opposite corner. After completing the defensive burial task, the animals were euthanized, perfused, and the tissues processed for the following analysis: 1) column morphology studies using the lipophilic dye DiI, 2) matrix metalloproteinase activity. (MMP) was quantified using zymography gel microinjections, 3) astrocyte morphology studies using GFAP-hM3dq-mCherry virus, and 4) IBA-1 expressing microglia/macrophage populations were analyzed semiquantitatively by immunohistochemistry. In addition, we analyzed single-cell Ca2+ dynamics in freely moving MSN D1 and D2 mice (D1 or D2 cre mice) using a miniature microscope (nVista) and a virally expressed Cre-dependent Ca2+ reporter (GCaMP8M). and recorded extinction to emphasize CS.

Results:Overall, we observed key features of CS stress-induced changes in pentapartite synaptic plasticity. Exposure to CS stress is associated with synaptic potentiation in the NAcore, quantified by an increase in dendritic spine head diameter and spine density, and an increase in matrix metalloprotease 9 activity, which catalyzes selected extracellular matrix (ECM) proteins. ). Exposure to CS stress also induced a downregulation of astroglial glutamate transporters (GLT-1) and retraction of astrocyte synapse coverage compared to control animals and NS stress. Furthermore, stressed CS animals produced changes in microglial morphology and in the number and volume of IBA-1+ cells compared to stressed control and NS animals. Furthermore, we observed different changes in Ca2+ dynamics in D1 vs. D2-MSN during the defensive burial task and extinction in CS-stress.

Conclusions:These data suggest that neuroadaptations and calcium dynamics coincident with a 15-minute burial defensive task may be correlated with synaptic plasticity in the NAcore, leading to differential stress coping responses. Previous laboratory data showed that CS-stress exposure did not provoke sucrose-seeking in sucrose-trained rats, so we hypothesize that the plasticity described here may indicate pathological features of a stress disorder.

Key words:Post-traumatic stress disorder, Nucleus accumbens, Calcium images

To disclose:Nothing to disclose.

Robert Fenster*, Kenneth McCullough, Sergey Naumenko, Yan Li, Andrew Thompson, Claudia Klengel, Joy Otten, Shu Dan, Torsten Klengel, Vadim Bolshakov, Kerry Ressler

McLean Hospital, Harvard Medical School, Belmont, Massachusetts, EUA.

Background:The ability of the medial prefrontal cortex (mPFC) to control top-down behavior is affected by stress. Stress is also known to induce transcriptional responses that influence long-term behavioral adaptations. However, the mPFC molecular response to stress is not fully understood, in part due to the cellular heterogeneity of the region. There is a great need for new therapeutic targets for stress-induced behavioral disorders.

Methods:We used simple nuclear sequencing (InDrops) to sequence over 100,000 mPFC nuclei after a stress-inducing Pavlovian fear conditioning trial (n = 8 groups of n = 2-3 male mice) and to identify differentially expressed genes. specific cell type after fear conditioning and fear expression. We used fluorescent in situ hybridization (FISH) and immunohistochemistry techniques to confirm cell clustering markers found with single nuclear sequencing (n=4-5 male mice). We used a combination of pharmacology, Cre/lox recombination, and behavioral cutting electrophysiology to functionally characterize candidates.

Results:We identified Ptgs2, which encodes cyclooxygenase 2, as an important candidate that is upregulated in layer II/III excitatory neurons after stress. Specifically, Ptgs2 along with Bdnf, Nptx2 and Lingo1 were transiently up-regulated with shock-induced learning and fear expression in a layer II/III neuronal population characterized by the neuronal excitatory gene Slc17a7 and the cell-type specific neuropeptide Penk. These cell-type specific dynamic expression patterns identified with snRNAseq were validated by quantitative fluorescent in situ hybridization. Using a pharmacological approach, we found that systemic lumiracoxib, a selective Ptgs2 inhibitor, resulted in a significant reduction in anxiety expression (2-way ANOVA, drug response, p = 0.03). Furthermore, genetic ablation of Ptgs2 in mPFC resulted in a reduction of stress-induced anxiety-like behaviors in the elevated plus maze (unpaired Student's t-test, p = 0.02). Layer II/III neurons expressing virus-induced Cre in a background of floxed Ptgs2 show baseline depolarization compared to neighboring untransduced cells (resting membrane potential, unpaired Student's t-test, p = 0.002).

Conclusions:Taken together, these results suggest that Ptgs2 is dynamically and cell-type-specific expressed in layer II/III Penk+ neurons in mPFCs and that its role in regulating prostaglandins and/or endocannabinoids within these neurons is important. an important mediator of stress that can be anxiety behavior

Key words:COX-1 and COX-2, anxiety and PTSD, medial prefrontal cortex, mouse models, single-core RNA sequencing

To disclose:Nothing to disclose.

Gina Kemp*, David Stellwagen

McGill University, Montreal, Canada

Background:Social stress buffering occurs when an animal exhibits a reduced stress response in the presence of a conspecific. Few studies have examined the underlying physiological changes that accompany this phenomenon, but the immune system has become a common denominator in the social buffering of stress. In rodents, socialization gave positive results for wound healing and stroke recovery. Indeed, it is well established that tumor necrosis factor (TNF), a key cytokine, plays an important synaptic role as a neuromodulator. We have recently demonstrated mechanistically that TNF mediates stress-induced plasticity (Kemp et al., In Press - Molecular Psychiatry, 2022). In this original poster, I present emerging evidence for links between socialization and TNF in the context of acute stress.

Methods:All experiments described were performed in accordance with the Canadian Animal Care Council reviewed and approved by the Montreal General Hospital Facilities Animal Care Committee. C57BL/6J mice between 8 and 16 weeks of age were subjected to two stress paradigms: forced swimming stress and restraint stress. Under both paradigms, animals were housed singly or in groups in new cages with their stressed siblings. Unstressed control groups were age-matched and exposed to the same housing and management conditions without stress paradigms. After 24 hours, the behavioral outcome of the acute stress response was assessed using the light-dark box test (10 minutes total) (Crawley & Goodwin, 1980). Time spent in the light box is inversely correlated with anxiety-like behavior. The biochemical performance of the acute stress response was also measured 24 hours after the stress: mice were euthanized with isoflurane, blood samples were collected by cardiac puncture, and bilateral ventral hippocampal tissue (vHPC) was excised to measure the biochemical stress performance.

TNF levels were measured using the mouse TNF ELISA kit (eBioscience, Mouse TNF alpha ELISA Ready-SET-Go! Kit #88-7324). Samples were standardized for total protein intake as measured with a Thermo Fisher Scientific Bicinchoninic Acid (BCA) Assay Kit (#23227). Samples were also tested for other cytokines using a Milliplex panel (Mouse High Sensitivity T-Cell, Millipore, St. Charles, MO, USA) and using the Bio-Plex™ 200 system (Bio-Rad Laboratories, Inc., Hercules, USA ). CA, USA). Serum corticosterone (CORT) was measured with an ELISA kit (Cayman Chemical, Cat. #501320).

Results:Anxiety-like behavior increased in single males undergoing forced swimming stress (FST) (Student's t-test; p = 0.0115, N = 9-10/group), but no comparable phenotype was found in females (T-test Student's, p = 0.5976, N = 7-8/group). It has already been shown that the described phenotype is associated with a significant increase in TNF in men (Kemp, In Press). Furthermore, solitary confinement alone in this environment does not increase anxiety-like behavior or TNF levels (Kemp, In Press).

Interestingly, in contrast to single-housed mice, group-housed mice did not exhibit an anxiety-like phenotype after FST (Student's t-test, p = 0.5066, N = 10-11/group). This observation was also replicated using constraint stress (one-way ANOVA F(2.31) = 7.440, p = 0.0023, Tukey post hoc analysis of control vs. individual housing after RS ​​p = 0.0047, control vs. group housing after RS ​​p = 0.9680, individual housing according to RS versus group housing according to RS p = 0.0073, N = 11-12/group). Furthermore, animals housed in the group showed a reduction in vHPC-TNF after stress (Student's t test p = 0.0439). Levels of four other cytokines, namely IL-1b, IL-10, IL-12 and MIP-2, were also significantly increased in post-stress socialized animals when tested with a cytokine multiplex (all one-way ANOVAs). , Tukey publication hoc analysis of control versus group housing after stress for IL-1b p=0.0356, IL-10 p=0.0432, IL-12 p=0.0331 and MIP-2 p= 0, 0403, N = 4-5/group)

When we tested corticosterone levels (CORT), preliminary data showed that TNF levels correlated better with anxiety-like behavior than CORT. Indeed, there was a major effect of prior stress exposure on serum CORT levels (24 hours post-stress; two-way ANOVA F(1,10) = 8.551, p = 0.0152, N = 3-4 /group) and there was no difference between group stress and simple stress in animals (p = 0.9952).

Conclusions:We report a moderating effect of post-stress housing conditions on anxiety-like behavior and TNF cytokine levels in vHPCs. Indeed, post-stress socially housed animals do not exhibit an anxiety-like phenotype and demonstrate active suppression of vHPC-TNF levels compared to post-stress single housed animals. Furthermore, we show an induction of other cytokines in the absence of anxiety-like behavior after stress. Therefore, these findings contribute to an ongoing scientific debate about whether resilience and vulnerability are two sides of the same coin, or whether they are two different phenomena, each with different mechanisms of action. In fact, our results indicate active molecular mechanisms involved in the social buffering of stress as a form of resilience. Further investigation of these mechanisms may give us a way to characterize the molecular basis of resilience.

Key words:Social stress buffer, cytokines, corticosterone, anxiety-like behavior, tumor necrosis factor

To disclose:Nothing to disclose.

Josephine McGowan*, Liliana Ladner, Claire Shubeck, Amanda Anquiera-Gonzalez, Christina LaGamma, Juliana Tapia, Ariana DeFrancesco, Tzong-Shiue Yu, Steven Kernie, Christine Ann Denny

Columbia University, New York State Psychiatric Institute, New York, New York, United States

Background:A traumatic brain injury (TBI) is a debilitating neurological disorder caused by the impact of an external force on the head. Traumatic brain injury causes persistent cognitive impairment, including the generation of fear, which is defined as the inability to distinguish between aversive and neutral stimuli. Fear generalization can be tested in mice using a contextual fear discrimination (CFD) paradigm that tests fear behaviors in learned neutral versus aversive contexts.

Methods:To identify the neural clusters of fear generalization impaired by TBI, we used ArcCreERT2 x Enhanced Yellow Fluorescent Protein (eYFP) mice, which allow for activity-dependent labeling and quantification of memory traces. ArcCreERT2 x eYFP mice received sham surgery or controlled cortical impact model (CCI) of TBI. One month after surgery, mice were injected with 4-OHT to open a labeling window and given a 1-shock contextual fear conditioning (CFC) paradigm. Mice were then administered CFD for an additional 5 days and sacrificed after exposure to aversive (A) or neutral (B) contexts. The neural activity of the dentate gyrus (DG) was quantified. (n = 13-15 mice/group). In a separate set of studies, we determined whether administration of (R,S)-ketamine 1 hour after CCI would reduce anxiety generalization in mice with TBI. (n = 6-8 mice/group).

Results:In the CFD paradigm (ANOVA: context x time *p = 0.0464; context p = 0.6064; time p < 0.0001), TBI mice showed greater fear generalization (for example, lack of differentiation between aversive and fearful fear). neutral). Context). This is in contrast to sham mice, which distinguished between aversive and neutral context (ANOVA: context x time ***p < 0.0001; context ***p < 0.0001; time ***p < 0.0001) . TBI did not alter the number of DG eYFP+ cells activated during fear coding (ANOVA: treatment x context p=0.7645; treatment p=0.7926; context p=0.9476) nor the number of DG c- fos+ during memory retrieval (ANOVA: treatment x context p=0.3028 treatment p=0.3138 context p=0.3166). Sham mice showed a significant increase in the percentage of DG eYFP + /c-fos+ cells stained in the aversive context compared to the neural context. However, TBI mice showed comparable percentages of eYFP+/c-fos+ stained DG cells in both settings (ANOVA - treatment x context p=0.4171; treatment p=0.2120; context **p=0.0030 ).

Finally, previous data in our laboratory have shown that a single administration of (R,S)-ketamine (30 mg/kg) before stress can attenuate learned anxiety and facilitate CFD. Here we report that administration of (R,S)-ketamine (30 mg/kg) 1 hour after CCI reduced TBI-induced fear generalization in mice (ANOVA - context x drug p =0.4111; context ** p = 0.0030, drug p = 0.1670).

Conclusions:Our data show that 1) TBI leads to greater generalization of anxiety; 2) this behavior is accompanied by alteration of fear memory traces in the DG; and 3) this behavioral deficit, which can be reversed by subanesthetic administration of (R,S)-ketamine after impact. This work improves our understanding of the neural basis of fear generalization in people with TBI and suggests potential avenues for future translational research.

Key words:TBI, (R,S)-ketamine, fear generalization, memory engram cell, hippocampus

To disclose:Nothing to disclose.

Joseph Stujenske*, Hermany Munguba, Vanessa Gutzeit, Ashna Singh, Noelle Eghbali, Melanie Kristt, Daniel Shaver, Sonal Thukral, Francis Lee, Johannes Broichhagen, Conor Liston, Joshua Levitz

Weill Cornell Medical College, New York, New York, USA. UU.

Background:Anxiety disorders are the most common psychiatric disorders, affecting approximately 30% of American adults at some point in their lives. Anxiolytic drugs act primarily through serotonergic or GABAergic signaling, whereas there are no approved treatments that act primarily through a glutamatergic mechanism. The metabotropic glutamate receptor 2 (mGluR2) is located primarily presynaptically and, together with mGluR3, mediates feedback inhibition of glutamate release. Mixed mGluR2/3 agonists have been shown to mediate anxiolytic effects in humans through an unknown mechanism. In this study, we describe different anxiolytic roles of mGluR2 in the medial prefrontal (mPFC) and insular (IC) projections to the basolateral tonsils (BLA).

Methods:Using adeno-associated virus in Grm2-Cre transgenic mice, mGluR2+ projectors were labeled in BLA. The specific roles of the mPFC and IC projections in anxiety-related behaviors were characterized using optogenetic techniques and fiber photometry. The specific function of presynaptic mGluR2 was investigated using a novel photopharmacological tool, photoswitchable remotely coupled orthogonal ligands, to specifically activate mGluR2 in prefrontal or insular terminals. Conventional and photopharmacological manipulations were performed during in vitro electrophysiological recordings to characterize its role in synaptic transmission and in vivo during behavioral tests that elicited various forms of fear-related avoidance responses. N = 5–20 male mice per group.

Results:Systemic administration of a mixed mGluR2/3 agonist (LY37) decreased spatial avoidance, whereas a mixed antagonist (LY34) increased avoidance. LY37 infused into the BLA also mediated anxiolysis. In projectors, mGluR2 was enriched with BLA from mPFC and IC. Neural activation of both cell populations was monitored during anxiety-related trials using fiber photometry. In vitro, 89% (n=19) and 100% (n=14) of BLA main neurons were activated by mPFC and mGluR2+ IC projections, respectively. This activation was acutely extinguished by mGluR2 photoactivation, whereas prolonged photoactivation induced a long-term depression. Acute photoactivation of mGluR2 in mPFC, but not IC terminals, reduced spatial avoidance, and prolonged photoactivation resulted in anxiolysis 4 h but not 7 days after light. In contrast, acute photoactivation of mGluR2 in IC, but not mPFC, resulted in decreased social avoidance and avoidance of predator urine. Photoactivation of mGluR2 in both projections reduced latency during novelty-suppressed feeding.

Conclusions:We describe distinct and overlapping anxiolytic roles of mGluR2 in mPFC and IC projections for the BLA. mGluR2 represents a promising therapeutic target for the treatment of anxiety.

Key words:Photopharmacology, GPCR, metabotropic glutamate receptor 2 (mGluR2), medial prefrontal cortex, basolateral amygdala

To disclose:Nothing to disclose.

Elizabeth Doolin, Dharam Paul, Julia Crossman, Michael Odontiadis, Susan O'Connor, Errol DeSouza*

Bionomics Ltd., Cambridge, Massachusetts, EE. UU.

Background:The DSM-5 describes Social Anxiety Disorder (SAD) as pronounced anxiety or fear of one or more social situations in which the person will be exposed to possible scrutiny by others. Examples include social interactions (eg, talking, meeting strangers), being watched (eg, eating or drinking), and appearing in front of others (eg, giving a speech). SAD is a chronic disorder that can also include severe episodes of acute anxiety, such as those triggered by performance-like events. In situations like these, a fast acting, safe and effective therapy would be beneficial. The only FDA-approved drugs for SAD are selected antidepressants (fluvoxamine, sertraline, paroxetine, venlafaxine), which are unsuitable for acute treatment due to their slow onset of action (2-4 weeks). While there are no approved medications to treat acute SAD, beta-blockers and benzodiazepines (BZDs) are used off-label. However, beta-blockers primarily treat physical symptoms (hot flashes, increased heart rate, tremors), whereas serious safety concerns associated with BZDs have limited their use.

BNC210 is a new drug that acts via negative allosteric modulation of the alpha-7 nicotinic acetylcholine receptor (α7 nAChR) and has received FDA fast track designation for the acute treatment of SAD and other anxiety disorders. It has been administered to over 400 participants in phase 1 and 2 clinical trials and is devoid of the serious side effects associated with medications that many SAD patients are currently taking. BNC210 has demonstrated anxiolytic effects on human behavior and neural correlates of anxiety in acute dose clinical trials (using a liquid suspension formulation of BNC210 given with food to facilitate absorption). In a CCK-4 challenge model of panic attacks in healthy volunteers, single doses of BNC210 significantly reduced the number and intensity of panic symptoms using the Panic Symptoms Scale (PSS). In patients with generalized anxiety disorder (GAD) performing the emotional faces task during fMRI, single doses of BNC210 significantly reduced two neural correlates of anxiety; Amygdala activation caused by looking at emotional faces and the connection between the anterior cingulate cortex and the amygdala (this connection is strong in pathological anxiety). In the same study, BNC210 significantly reduced threat avoidance on a behavioral task and reduced state anxiety (as measured by the State Trait Anxiety Scale) in patients with GAD.

BNC210 is currently being evaluated in a phase 2 study for the acute treatment of SAD (PREVAIL study, NCT05193409). Using a new oral tablet formulation of BNC210 with improved absorption characteristics compared to the previously used suspension formulation, single doses of BNC210 (225 mg or 675 mg) are compared with placebo (n = 50 per group) to reduce anxiety speech challenge induced as measured by the Subjective Units of Distress Scale (SUDS) in patients with SAD.

Methods:A new solid tablet formulation of BNC210 containing a spray dried dispersion of BNC210 was developed to improve the solubility of the compound. During the development process, several prototype formulations were compared in in vitro dissolution assays and master formulations in canine pharmacokinetic (PK) studies. The selected final formulation was then evaluated in two single-dose human oral pharmacokinetic studies to compare the pharmacokinetic properties of the tablet versus the suspension formulation (BNC210 300 mg, fed versus fasted) and then the pharmacokinetic parameters and linearity of the dose with increasing doses of to diagnose the new tablet (300 to 1200 mg of BNC210, fasting).

Results:The first human pharmacokinetic study showed that the final formulation developed for the BNC210 tablet overcame the feeding effect of the liquid suspension. At the 300 mg dose, the liquid suspension showed a significant increase in mean Cmax (2.3-fold) and mean AUC (3.5-fold) after a high-fat meal compared to a fasting meal while at the same dose. had little effect on the values ​​of these pharmacokinetic parameters of the tablets, regardless of whether they were taken with or without food (mean Cmax decreased slightly by 12% and mean AUC increased by only 27% when taken). 🇧🇷 In addition, the tablet reduced the median time to peak plasma concentration (Tmax) from 4 hours with a high-fat meal to 1.75 hours in the fasted state. Pharmacokinetic parameters for single dose administration of the tablet showed linear dose exposure in the range of 300 mg to 1200 mg of BNC210 in the fasted state, and the median Tmax was 0.75 to 1.75 hours in the fasted state.

Conclusions:BNC210 has been reformulated into a tablet with improved pharmacokinetic properties, which may make it suitable for PRN use in an outpatient setting to treat SAD. Drug exposure is no longer dependent on concomitant food intake and peak plasma concentrations are reached approximately 1 to 1.5 hours post-dose. This means that BNC210 can be taken just before an expected anxiety-provoking event, such as a presentation or social event. Furthermore, plasma concentrations remain at reasonable levels for several hours after peak concentrations are reached, suggesting that repeat dosing may not be necessary. Primary data from the ongoing phase 2 BNC210 study on the acute treatment of SAD (PREVAIL study, NCT05193409) are expected in late 2022 or early 2023.

Key words:Social anxiety disorder, acute care, phase II clinical trial, BNC210

To disclose:Nothing to disclose.

Elizabeth Doolin, Dharam Paul, Susan O'Connor, Paul Rolan, Julia Crossman, Michael Odontiadis, Errol DeSouza*

Bionomics Ltd., Cambridge, Massachusetts, EE. UU.

Background:Currently approved therapies for post-traumatic stress disorder (PTSD) have side effects and limitations that create an unmet medical need for more effective and better tolerated therapies. BNC210 is a first-class negative allosteric modulator of the alpha-7 nicotinic acetylcholine receptor (α7 nAChR) under development for the treatment of trauma and stress-related disorders and anxiety disorders. Extensive characterizations in clinical and non-clinical studies have revealed several properties with potential to treat PTSD symptoms and some of the known pathophysiology underlying PTSD. BNC210 has received Fast Track designation from the FDA for the treatment of PTSD and other trauma and stress-related disorders and is currently being evaluated in a phase 2b monotherapy study in approximately 200 patients with PTSD (ATTUNE study, NCT04951076).

BNC210 was previously evaluated in a Phase 2 PTSD study (RESTORE study, NCT02933606) in which participants received BNC210 (150, 300, or 600 mg) or placebo twice daily. in a liquid suspension formulation to be taken with food for optimal absorption. No significant differences from placebo were measured on the physician-administered PTSD scale for DSM-5 Total Symptom Severity Score (CAPS-5) during the 12-week treatment period. However, positive insights from the study data included: statistically significant effects on depression symptoms (CAPS-5 criterion D) at early time points and no trend toward increased adverse events, cognitive impairment, suicidal ideation, or worsening behavior with the treatment. Population pharmacokinetics (PK) estimated plasma drug exposure (AUC) in participants and found that the liquid suspension produced less than predicted exposure in the outpatient setting, a finding that triggered the development of a new oral tablet formulation of BNC210. Pharmacometric modeling was performed to investigate an exposure-response relationship (PK/PD) for BNC210 based on estimated AUCs and observed CAPS-5 scores.

Methods:Population pharmacokinetic model: Plasma samples were collected from RESTORE study participants at 3 time points over a 12-week period and BNC210 levels were measured. Population pharmacokinetic analysis was performed using these data and AUC values ​​were estimated using a one-compartment pharmacokinetic model that allowed for time-varying bioavailability.

PK/PD Model: A PK/PD analysis was performed to assess the exposure-response relationship for BNC210 AUC estimates and CAPS-5 total symptom severity scores as a continuous direct effect. The effect was modeled on the logit scale, preventing it from being greater than the highest possible score or less than the lowest possible score. Effects were evaluated using three models: linear, Emax and power function.

Reformulation: Spray-dry dispersion technology was applied to develop a solid dose oral tablet formulation of BNC210 with improved solubility, which could overcome the limitations of liquid suspension, especially the strong effect of food and non-linear absorption. Three human pharmacokinetic studies were conducted to compare the pharmacokinetic parameters of tablets versus suspension, to establish dose linearity with increasing single doses, and to determine a dosing regimen that could be used in future PTSD clinical studies.

Results:Population pharmacokinetic modeling: Modeling showed that the estimated AUC values ​​of BNC210 in the RESTORE study outpatient study were lower than expected and higher doses of BNC210 were associated with decreased bioavailability over time. After 12 weeks of treatment, the estimated exposure achieved for the 600 mg b.i.d. The group dose was ~50% lower than previously measured in a 7-day clinical pharmacokinetic study.

PK/PD model: An inhibitory Emax model, which includes estimates of between-subject variability, produced the best fit of the PD model and predicted an exposure-response relationship for total CAPS-5 symptom severity scores (p-value < 0.01) where higher AUC values ​​occur were associated with a greater effect. The model predicted that the AUC90 (90% of peak drug effect) would be ~25,000 ng.h/mL, corresponding to a predicted difference from placebo in CAPS-5 in the potentially clinically significant range.

Reformulation: In single-dose human pharmacokinetic studies, the BNC210 tablet outperformed the feeding effect of the suspension formulation, eg B. a 300 mg dose (fed and fasted) achieved the respective mean Cmax values ​​of 1528 and 1727 ng/mL and AUC values ​​of 14,000 and 11,000 ng.h/mL, and exposure was dose-linear in the range of 300 to 1200 mg. A multiple-dose pharmacokinetic study (900 mg twice-daily tablet formulation) achieved more than the target exposure of 25,000 ng.h/mL for further evaluation of BNC210 in a PTSD study.

Conclusions:Population pharmacokinetic modeling showed that exposure to the liquid suspension formulation of BNC210 was insufficient to achieve efficacy in the RESTORE PTSD study, in which the estimated mean AUC at steady state for the 600 mg twice daily weekly dose group 12 was only 10,900 ng.h/ml However, the pharmacometric model predicted the potential for BNC210 to have a benefit in PTSD, provided adequate blood levels could be achieved. These analyses, along with the development of the new tablet formulation, ensured further evaluation of BNC210 in patients with PTSD and provided a basis for the optimal design of the ongoing Phase 2b efficacy study in PTSD (ATTUNE study, NCT04951076); First-line data is expected in mid-2023.

Key words:PTSD, Phase II Clinical Trial, Exposure-Response Model, Reformulation, BNC210

To disclose:Nothing to disclose.

Charles Verdonk*, Adam R. Teed, Evan J. White, Xi Ren, Jennifer L. Stewart, Martin P. Paulus, Sahib S. Khalsa

Laureate Institute for Brain Research, Tulsa, Oklahoma, EUA.

Background:Altered perceptual processing of signals originating in the body (ie, interoceptive dysfunction) has been associated with anxious psychopathology. In a recent pharmaco-fMRI study, we demonstrated that individuals with generalized anxiety disorder (GAD) exhibit autonomic hyperresponsiveness, manifested by increased heart rate, increased interoceptive awareness of cardiorespiratory sensations, increased anxiety, and an attenuated neural response that occurs in the cortex. ventromedial prefrontal. during low beta-adrenergic stimulation (Teed et al (2022)). Here, we examined whether peripheral adrenergic modulation of cardiac signals with isoproterenol modulates heartbeat evoked potential (HEP), an electroencephalogram (EEG) marker of neural activity in response to heartbeat, in women with GAD compared with healthy comparators. (HC).

Methods:Simultaneous EEG-fMRI data were obtained from this randomized crossover clinical trial in 52 adult women (26 GAD, 26 HC, matched for age and body mass index (BMI), the same study population as Teed et al. (2022) )) during the administration of combined intravenous bolus infusions of isoproterenol (0.5 and 2.0 micrograms, μg) and saline, each administered twice in a double-blind fashion in a single scanning session. Participants continuously rated the perceived intensity of their cardiorespiratory sensations by turning an MRI-compatible scale during each infusion. EEG and electrocardiogram (ECG) signals were recorded during each 240-second infusion using an MRI-compatible 32-lead scalp EEG system, including simultaneous single-lead ECG. During off-line processing, the data were band-filtered between 0.3 and 30 Hertz, and the EEG data referenced to the common average signal. Cardiac R-wave peaks were detected from the ECG signal for each heartbeat using a semi-automated approach. EEG data were categorized by event based on epoch, from -100 milliseconds (ms) to 650 ms after the ECG R peak, using the cardiac R wave as a temporal reference. We have minimized various cardiac artifacts in the EEG signal, including cardiac field artifact and ballistocardiogram artifact, by applying ideal background set approach followed by independent component analysis to remove residual ballistocardiogram artifact. Baseline correction was performed by subtracting the mean of the 100ms window prior to the time of statistical analysis from the total mean of the HEP large signal. We implemented a data-based, permutation-based, cluster-based statistical analysis approach to compare HEP amplitudes during isoproterenol and saline infusions in GAD versus HC subjects over the time interval [100-600 ms] after the R peak.

Results:The GAD group (mean age: 26 ± 7 years, BMI: 25.8 ± 4.8) and the HC group (mean age: 24 ± 5 ​​years, BMI: 24.1 ± 3.2) did not differ in relation to age or BMI. During the peak response phase of the 0.5 μg dose of isoproterenol, the GAD group showed changes in HEP ​​amplitude that differed significantly from the HCs in the right centroparietal electrodes; In particular, the HEP amplitude was most positive during the peak response period in GAD (Cohen d = 1.18; P < 0.001) within a latency of 216–272 ms after the R peak. , HEP amplitudes were most negative within a latency period of 528 to 592 ms after the R peak (Cohen d = 0.90; P < 0.01). Furthermore, the GAD group reported significantly greater increases in the intensity of cardiorespiratory sensation compared to the HC group during the 0.5 μg dose of isoproterenol (Cohen d = 0.80; P < 0.01) that were not significantly related to with HEP amplitude changes correlated with trend level in all participants (maximum response: r = -0.25, P = 0.08; baseline recovery: r = -0.27, P = 0.05). During saline infusion, the GAD group also showed increased HEP amplitude in the right frontocentral electrodes (Cohen d = 0.97; P < 0.001) within a 92 ms window which was 224 ms after the start of saline infusion. peak R. Control analyzes showed that the altered PHE amplitudes observed in GAD vs. HC were not due to cardiac confounders such as differences in heart rate or T-wave amplitude. At the transdiagnostic sample level, correlation analysis of physiological and psychological indices showed that HEP amplitudes were significantly correlated in opposite directions with the anxiety subscale of the PROMIS Negative Affect Questionnaire (0.5 μg of isoproterenol: r = 0.46, P < 0.001; saline solution: r = -0.42, P < 0.01) and with the subscale " Physical Concerns" from the Anxiety Sensitivity Index Questionnaire (0.5 μg isoproterenol: r = 0.47, P < 0.001; saline: r = -0.34, P < 0.01). No significant HEP changes or multilevel associations were observed with the 2 µg dose.

Conclusions:In this study, subjects with GAD exhibited impaired HEP and increased cardiac interoceptive sensing, consistent with autonomic hyperresponsiveness during low-level peripheral adrenergic stimulation. These and previous results support the hypothesis of increased bottom-up sensitivity to adrenergic excitation signals in the disorder. Furthermore, the heightened HEP responses observed during saline infusion suggest that individuals with GAD may also exhibit top-down sensitivity to heartbeat signals, possibly associated with abnormal processing of cognitive signals. Taken together, our results support the notion that people with GAD exhibit peripheral autonomic hypersensitivity that contributes to dysfunctional cardiac interoception in this condition.

Key words:Generalized anxiety disorder, interoception, heartbeat evoked potential, cardiac sensation

To disclose:Nothing to disclose.

Stacey Versavel*, Rachel Gurrell, Ih Chang, Ann Dandurand, Sridhar Duvvuri, Amy Giugliano, Gina Pastino, Theresa Pham, Gabriel Jacobs, Koshar Safai Pour, Rob Zuiker, Raymond Sanchez, John Renger

Terapéutica Cerevel, Cambridge, Massachusetts, EE. UU.

Background:Panic disorder (PD) is a serious condition that can cause significant mental and physical distress. Parkinson's is associated with dysregulation in fear and anxiety neurocircuitry that include serotonin, norepinephrine, and gamma-aminobutyric acid (GABA) signaling pathways, and current pharmacotherapy mainly consists of medications that target these systems, such as selective GABA reuptake inhibitors. serotonin and benzodiazepines (BZDs). 🇧🇷 However, no single drug class adequately addresses the subjective (eg, anxiety, terror) and somatic (eg, tachycardia) symptoms of PD. Therefore, a significant proportion of patients with Parkinson's have an incomplete or partial response to available treatments, with a low probability of remission and a significant probability of relapse. With no new drugs approved to treat Parkinson's disease since 2005, there is a need for new and innovative treatment options.

There is substantial non-clinical evidence that the α2/3 subunit GABAA receptors are responsible for the anxiolytic effects of benzodiazepines and that the α1 subtype is associated with sedative properties. Darigabat was rationally designed to have non-sedative anxiolytic potential, selectively enhancing GABA action at α2/3/5 GABAA receptor subtypes, preserving activity at α1, and is under development for the treatment of neurological and psychiatric diseases. To characterize the potential panicolytic effect of darigabat, CO2 inhalation was applied as an experimental model to reliably induce panic and anxiety in healthy participants. The model is sensitive to pharmacological manipulation by anxiolytics, allowing the study of pharmacodynamic effects of drugs in the early stages of clinical development.

Methods:In this active randomized, double-blind, placebo-controlled study, we examined the panicolytic effect of multiple doses of darigabat on CO2-induced panic and anxiety symptoms in healthy participants (NCT04592536). Only people sensitive to the anxious effects of double breathing with 35% CO2 in the screening were eligible for randomization. In this two-sequence, two-period partial crossover design, each eligible participant was randomized to receive placebo and one of three active treatments in 3 separate cohorts (n=18-20/cohort) for 8 days: Cohort 1 Darigabat 25 mg BID, cohort 2 alprazolam 1 mg BID and cohort 3 darigabat 7.5 mg BID. Darigabat was titrated to reach the target maintenance dose on day 5. On day 8 of each crossover period, a CO2 test was performed 3 hours after dosing. Alprazolam was used as a positive control to determine assay sensitivity. While each participant's placebo period served as its own control, the change in panic and anxiety symptoms before and immediately after CO2 inhalation was measured using the Panic Symptom List IV Total Score (PSL-IV; primary endpoint) and the visual analogue scale for anxiety. (VAS anxiety; secondary outcome). The PSL-IV contains 13 items derived from those listed in the Diagnostic and Statistical Manual of Mental Disorders Version 4 (DSM-4) for panic disorders and covers aspects of the Parkinson's experience, including psychological aspects (such as fear of death) and physiological aspects. (such as palpitations and shortness of breath). Cardiovascular parameters (blood pressure and heart rate) were objectively monitored continuously using a non-invasive finger cuff-based hemodynamic monitoring system (Finapres) for approximately 15 minutes before and after measuring the CO2 challenge. To determine the effects of pharmacological treatment on the physiological panic and anxiety response (secondary end point). Although the study was not prospectively designed for formal hypothesis testing, nominal P values ​​are provided for each comparison. Steady state pharmacokinetic samples were obtained 2 and 4 hours after dosing on day 8.

Results:For the primary endpoint, PSL-IV total score at day 8, the darigabat 7.5 mg and 25 mg twice daily treatment groups showed an improvement of 3.9 points (P = 0.036) and 4.5 points (P = 0.008) im, respectively, compared with placebo. For the VAS secondary endpoint of anxiety, the 7.5 mg and 25 mg twice daily treatment groups showed an improvement of 12.8 points (P = 0.026) and 7.8 points (P = 0.282), respectively, compared to placebo. Compared with placebo, alprazolam 1 mg twice daily showed results that were in line with expectations, with placebo-adjusted improvements of 1.6 points (P = 0.286) and 0.9 points (P = 0.876) in the total score of PSL-IV and VAS anxiety on day 8, respectively. The results for each PSL-IV item showed a large reduction in the psychological and physiological symptoms that occur as a result of CO2 inhalation.

Both doses of darigabat attenuated the transient increase in blood pressure induced by CO2 inhalation on day 8, suggesting that darigabat reduces the physiological response associated with CO2 challenge. Alprazolam did not attenuate the physiological response associated with CO2 challenge.

Darigabat plasma concentrations were consistent with previous studies and were estimated to achieve approximately 50% and 80% receptor occupancy in α2-containing GABA A receptors at 7.5 mg and 25 mg twice daily, respectively. Darigabat was generally well tolerated.

Conclusions:This study demonstrated the panicolytic potential of darigabat based on the reduction of acute panic and anxiety symptoms in a validated experimental clinical panic model in healthy participants. These data warrant further evaluation of darigabat in patients with anxiety disorders.

Key words:GABA-A, positive allosteric modulators, panic, new therapies, experimental methods

Disclosures: Cerevel Therapeutics: Employee (himself) Eliem Therapeutics: Employee (Spouse), vZenium: Founder (Spouse)

Mauricio Caceres Chacon*, Sian Rodríguez Rosado, Gabriela Hernández Busot, Alexdiel Figueroa Pérez, Hector Haddock Martínez, Melissa Rivera López, Osmarie Martínez Guzmán, Demetrio Sierra Mercado

University of Puerto Rico, San Juan, Puerto Rico

Background:The increasing diagnosis of mental health disorders such as anxiety has created the need to examine external factors that may contribute to the development of these disorders. Recently, epidemiological studies have begun to show associations between exposure to environmental pollutants and anxiety disorders. One possible contaminant is the widely used herbicide glyphosate, which has been identified in food and water sources. Originally, glyphosate was thought to be safe for mammals because it inhibits a metabolic pathway that is almost exclusively plant-based. However, a link has been found between a higher diagnosis of anxiety and glyphosate use. Glyphosate, like other potential contaminants, is regulated by the Environmental Protection Agency (EPA). The EPA has established a chronic reference dose of 2.0 mg/kg for glyphosate to avoid adverse health effects. However, the effect of glyphosate at this dose on the development of anxiety has not been studied. Therefore, we want to evaluate the effect of glyphosate on anxious and exploratory behavior. Since both the amygdala and the prefrontal cortex have been shown to play important roles in the expression and modulation of fear and exploration, we intend to probe these brain regions for neural activity to identify a mechanism for eventual behavioral changes.

Methods:Male rats (n=13) received water containing glyphosate ad libitum for 16 weeks. Water consumption was measured weekly and water was prepared to a target dose of 2.0 mg/kg glyphosate per day. Control rats (n = 12) received filtered drinking water. Anxiety-like behaviors were assessed after 10 weeks of exposure in an elevated plus maze (EPM). Exploratory response to novelty was measured at 14 weeks using an open field with a new object at the center (NOET) and at 16 weeks using an auditory startle response test (ASR, 5 repetitions of a new sound in a familiar context). The mice were then sacrificed and the brain tissue was fixed and collected. Immunohistochemistry for c-Fos was performed on brain slices containing amygdala and on the prelimbic (PL) and infralimbic (IL) cortices of the prefrontal cortex to assess neuronal activity. Student's t test was used for analysis of behavioral results and immunohistochemical analysis.

Results:In EPM, glyphosate reduced open arms time (glyphosate: 51.4; control: 108.9; t22 = 2.98; p = 0.0069), indicating increased anxiety. In NOET, glyphosate reduced interaction time with novel objects (glyphosate: 45.34; control: 97.9; t22 = 2.73; p = 0.0122), consistent with decreased exploration. Furthermore, glyphosate increased the percentage of freezing time in the presence of a new sound (glyphosate: 14.38; control: 5.94; t23 = 2.094; p = 0.0475), indicating greater startle in a new stimulus and neutral. Brain tissue analysis showed that glyphosate did not affect neuronal activity in PL (glyphosate: 270.5; control: 382.0; t10 = 1.365; p = 0.2023), IL (glyphosate: 201.4; control: 253.3; t10 = 1.059; p = 0.3147) or amygdala (glyphosate: 98.83; controls: 100.3; t10 = 0.1318; p = 0.8978).

Conclusions:Contaminants such as glyphosate, even at doses considered safe by the EPA, can increase anxiety-like behaviors and decrease exploration in rats. These findings support the idea that environmental pollutants should be evaluated for their adverse effects on mental health. More research is needed on the mechanism by which pollutants like glyphosate cause changes in behavior. Future directions include performing immunohistochemistry in brain regions involved in anxiety-like behaviors, such as the bed nucleus of the stria terminalis and the ventral hippocampus.

Key words:Anxiety, mental disorders, animal models, environmental risk factors

To disclose:Nothing to disclose.

Morgan Bartolomé*, Thomas Metzler, Thomas Neylan, Sabra Inslicht

UCSF, San Francisco VA Medical Center, San Francisco, California, USA

Background:Elaborate emotion regulation strategies such as cognitive reappraisal and expression suppression share common neural mechanisms with learning and fear extinction (Birthe Macdonald, 2020). Impaired fear extinction and learning processes are believed to support the severity of post-traumatic stress disorder (PTSD) symptoms. In healthy populations, the application of cognitive reappraisal is associated with less acquisition of fear learning and greater extinction learning and memory (Andrea Hermann, 2014). Other studies have not shown an association between explicit RE strategies and fear conditioning/extinction learning (Haruka Kitamura, 2022), suggesting that further consideration of individual factors is needed. PTSD has been associated with increased use of speech suppression, as well as changes in fear conditioning, extinction, and extinction retention (A J Khan, 2021; Inslicht et al., 2013; Orr et al., 2000). Further characterization of the relationship between ER processes and fear learning processes in trauma-exposed individuals may help us to target skills to increase the effectiveness of PTSD interventions.

Methods:A laboratory study was performed on traumatized men and women with and without PTSD to examine the effects of emotion regulation styles on fear conditioning and extinction. Tendencies toward cognitive reappraisal and expression suppression were assessed using the Emotion Regulation Questionnaire. Participants underwent a procedure developed by Orr et al. (Orr et al., 2000) and previously described (Inslicht et al., 2013), which was carried out over three sessions. All psychophysiological testing sessions were performed in a dedicated psychophysiological laboratory. The UCS was an electrical pulse of 500 ms duration ranging from 0.5 to 5.0 mA, previously classified by the participant as "very uncomfortable, but not painful". During the first session, participants underwent a habituation period during which they were presented with 5 of each of the colored circles (as CS +  and as CS-) without shock (UCS). This was followed by the fear acquisition phase, in which each presentation of the CS+ was followed by a 500 ms shock and the CS- was not. The anxiety erasure session took place 72 hours after the first session. During this session, participants were presented with 10 unenhanced presentations of CS+ and CS-. One week after extinction, an extinction session was performed. Participants viewed 4 unamplified presentations of each CS+ and CS-.

Results:A diagnosis of PTSD was found to weaken the relationship between cognitive reassessment and differential SCR response to CS+ and CS- during acquisition (z=2.23, P=0.02). People without PTSD showed a greater negative relationship between cognitive reappraisal and differential SCR, such that greater cognitive reappraisal predicted reduced differential SCR during anxiety acquisition (z = -2.00, P = 0.05). People with PTSD showed no significant association between cognitive reappraisal and differential SCR (z = 0.49, P = 0.62). PTSD did not moderate the relationship between expressive suppression and differential SCR response during extinction learning as predicted (P = 0.33). However, there was a main effect of expressive suppression on differential SCR during absorbance learning, such that stronger expressive suppression predicted greater differential SCR during absorbance retention (z = 2.06, P = 0.04) . No group differences were observed in the use of cognitive reassessment and speech suppression between those with and without a PTSD diagnosis.

Conclusions:The current analysis adds to the evidence that cognitive reappraisal predicts less fear acquisition. Furthermore, our data suggest that expressive suppression predicts fear response maintenance in the presence of safety cues, suggesting that miscoding of the inhibitory association between CS +  and shock during extinction learning is related. This suggests that common mechanisms are influenced by these two conceptually distinct facets of emotions: explicit emotion regulation and fear conditioning. Contrary to the hypothesis, no differences in ER strategies were observed between the PTSD groups in our sample, and the diagnosis of PTSD did not moderate the relationship between expressive suppression and retention of extinction. Several methodological considerations may explain this finding, including the fact that our control group consisted of people who had already been exposed to trauma but never met the criteria for PTSD. Future work should include the inclusion of a non-traumatized control group to further clarify these relationships.

Key words:Fear conditioning and extinction, emotion regulation, PTSD

To disclose:Nothing to disclose.

Carole Morel*, Sarah Montgomery, Long Li, Emily Teichman, Barbara Juarez, Romain Durand-de Cuttoli, Nikos Tzavaras, Scott Russo, Eric Nestler, Erin Calipari, Allyson Friedman, Ming-Hu Han

Icahn School of Medicine at Mount Sinai, New York, New York, United States of America

Background:Comorbidity is the norm rather than the exception, with more than 93% of Medicare dollars going to patients with comorbidities in the United States. Anxiety, anhedonia, and depression are highly prevalent comorbid symptoms in people's neuropsychiatric profiles. This co-occurrence is associated with complex symptoms, greater resistance to treatment, chronicity, disability and higher rates of suicide attempts in patients with comorbidity. However, common or separate mechanisms remain largely unknown. Clinical and preclinical studies have implicated ventral tegmental area (VTA) dopamine circuits in the etiology of anxiety, anhedonia, and depressive phenotypes. VTA dopamine neurons project widely throughout the brain, including emotional brain regions such as the cortex, nucleus accumbens (NAc), and amygdala (AMG). Here, we intend to identify parallel changes in dopaminergic circuits and how they control single or concomitant anxiety, anhedonia, and depressive behaviors after exposure to chronic stress.

Methods:We used a chronic social defeat stress (CSDS) paradigm known to induce individualized and complex stress-related behavioral outcomes to assess single or concurrent measures of anxiety, anhedonia, and depressive behavior in mice. After CSDS, we assessed social behavior, reward sensitivity and processing, and approach/avoidance behavior. We used viral strategies and transgenic mice to isolate VTA dopamine circuits and isolate VTA dopamine neurons that project to the AMG from VTA dopamine neurons targeting the NAc. We then combine techniques for studying neural circuits with in vivo fiber photometry and electrophysiological approaches to define the physiological properties and dynamics of VTA dopamine circuits that arise in response to CSDS exposure. We also use optogenetics to selectively link VTA circuit activity to different stress-induced behavioral outcomes.

Results:We first observed that CSDS influences depressive behavior (ANOVA, P<0.01, n=40), changes in cognitive function (ANOVA, P<0.05, n=28) and anxiety-like behavior (Kruskal-Wallis, P<0.01, n = 40), which occur independently of the depressive phenotype (Spearman r = 0.07; r = 0.06, P > 0.05, n = 25). Our circuitry probing approaches revealed that the VTA-AMG and VTA-NAc dopamine circuits arise from two distinct neuronal populations. Consistent with our previous studies showing that VTA-NAc dopaminergic neuron hyperactivity encodes social avoidance behaviors, whereas VTA-AMG dopaminergic neuron hyperactivity is associated with anxiety-like behaviors, we find here that CSDS circuit dynamics, VTA-AMG and VTA-NAc changed differently. We defined that VTA-AMG circuit activity selectively regulates anxiety-like behaviors after exposure to social stress, but not social avoidance behaviors, whereas VTA-NAc circuit dynamics regulate processing and reward behavior. social (ANOVA, P<0.05, n = 11) . We also observed significant extrinsic and intrinsic physiological changes of VTA-NAc and VTA-AMG compared to control mice (ANOVA, P < 0.01, n = 10-12). Finally, our physiological studies demonstrate that anxiety-like behaviors are associated with reduced VTA-AMG circuit activity and increased excitability of AMG neurons (Kruskal-Wallis, P<0.01, n=8-10; ANOVA, P<0.05, n=10 -12).

Conclusions:More than 50% of patients suffering from anxiety or major depressive disorders report a history of other mental illnesses. The complex and variable symptomatology that occurs after chronic exposure to stress, an important risk factor for triggering psychiatric disorders, challenges the preclinical picture for a single brain circuit/phenotype. Here, our results demonstrate that chronic exposure to social stress induces opposing cellular and physiological changes in parallel VTA circuits. Our studies identify reduced VTA-AMG circuit activity as a common biomarker and treatment target for anxiety-like behaviors in complex symptomatology, such as singular or coexisting anxiety with depression-like phenotypes. Therefore, our studies provide information for future clinical trials using the different dopamine pathways as drug targets for anxiety, anhedonia and depressive disorders.

Key words:Anxiety, depression, dopamine circuits, in vivo fiber photometry, electrophysiological approaches

To disclose:Nothing to disclose.

Denisse Paredes*, David Morilak

University of Texas Health Science Center at San Antonio

Background:Psychiatric disorders such as post-traumatic stress disorder and major depressive disorder are characterized by deficits in cognitive flexibility. Exposure therapy can be effective in reversing cognitive deficits in these patients. Fear extinction in rodents is similar to exposure therapy. Extinction reverses chronic stress-induced deficits in cognitive flexibility on the Attention Shift Test (AST), an executive process mediated by the medial prefrontal cortex. Extinction requires activity of pyramidal neurons in the infralimbic cortex and BDNF-initiated signaling cascades to reverse stress-induced impairments in configurational switching. However, the circuitry mechanisms that control BDNF suppression-mediated plasticity in the infralimbic are unknown. The ventral hippocampus plays a key role in regulating infralimbic activity during extinction learning, and plasticity in the ventral hippocampus is necessary for consolidation of extinction memory. In these experiments, we investigated the role of input from the ventral hippocampus (vHipp) to the infralimbic (IL) cortex in the effects of extinction following chronic stress to reverse cognitive deficits in male and female rats.

Methods:To selectively inhibit or activate input from the ventral hippocampus into the infralimbic, we inject AAV-CaMKIIa-hM4D(Gi)-mCherry or AAV-CaMKIIa-EGFP into the ventral hippocampus. Immediately before extinction, mice received bilateral microinjections of CNO into the IL to silence the ventral ends of the hippocampus into the IL. In separate experiments, stressed rats received AAV-CaMKIIa-Gq in the ventral hippocampus (and CNO in IL) to activate ventral hippocampal ends in IL rather than extinction. 24 hours after treatment, rats were tested on the AST to assess cognitive flexibility.

Results:Our results show that chemogenetic silencing of vHipp pyramidal cell input to IL blocks BDNF TrkB receptor phosphorylation and prevents extinction effects by reversing stress-induced cognitive deficits (n=10-12/group, p<0.01 ). Furthermore, we show that activation of the vHipp input in IL without extinction is sufficient to reverse stress-induced deficits in sentence switching (n = 6-12/group, p < 0.01). Importantly, the effects of activating the vHipp terminals in the IL are dependent on BDNF signaling, as local infusion of a neutralizing antibody into the IL prevented these beneficial effects.

Conclusions:These results suggest that vHipp-driven BDNF signaling in IL is critical for extinction to counteract the deleterious cognitive effects of chronic stress.

Key words:Extinction, ventral hippocampus, infralimbic cortex, BDNF

To disclose:Nothing to disclose.

Sabra Einblick*, Morgan Bartholomew, Connie Fee, Thomas Metzler, Thomas Neylan

University of California, San Francisco, San Francisco, California, USA. UU.

Background:The fear conditioning model has been used extensively to explain features of PTSD, including intrusive memories and symptoms of hyperarousal that underlie chronic physiological changes in sympathetic and neuroendocrine activity. In cross-sectional laboratory studies, enhanced fear conditioning and impaired extinction have been associated with PTSD. If it has been suggested that "conditionability" is similar to a tear and reflects the learning mechanisms that occur during the time after threatening traumatic experiences, few works have validated this explanatory model highlighted in PTSD during continuous traumatic stress in it real world. The theoretical model would predict that more conditional or impaired extinction people would be more sensitive to the real-world threat stress that many experienced during the COVID-19 pandemic. Our overall objective was to test the ecological validity of the fear conditioning model by examining whether pre-pandemic fear conditioning responses predict stress reactivity during COVID-19. We predicted that greater fear conditioning (greater differential skin conductance responses to CS+ vs. CS- stimuli during acquisition) and lower absorbance (greater differential skin conductance responses to CS+ vs. CS- stimuli during acquisition). absorbance) are associated with increased stress related to COVID-19

Methods:We conducted a longitudinal follow-up study of a pre-existing cohort of trauma-naive PTSD participants who had already completed fear conditioning experiments. Extensive data were previously collected from 208 men and women (50% women); Age 18-65. PTSD status was previously determined based on DSM-IV criteria using the Physician Administered PTSD Scale (CAPS), which was administered prior to the pandemic. Participants were previously subjected to a fear conditioning and extinction procedure (with shock as the unconditional stimulus) that occurred during two study visits 72 hours apart. Follow-up measures assessed exposure to COVID-19, including self-reported illness in self, family, close contacts, severity of illness, and reactivity to COVID-19-related stress using the COVID-19 Event Impact Scale., Ruminant Response Scale, Yale Brown Obsessive - Compulsive Scale and Perceived Stress Scale. Hierarchical linear regressions were performed on each stage (fear conditioning, fear eradication) separately with different skin conductances (CS+ vs CS-) to predict stress symptoms during COVID-19.

Results:Lower differential responses during fear conditioning were associated with higher scores for severity of obsessive-compulsive symptoms (beta = -.17, p <.05). Lower differential responses during extinction anxiety were associated with major COVID-19-related interventions (beta = -0.29, p = 07), rumination, beta = -0.35, p < 0.05), and perceived stress ( beta = -) united. 41, p < 0.05). Coefficients for all other variables showed effects in the same direction but were not significant.

Conclusions:Our results suggest that pre-pandemic responses during laboratory fear conditioning and extinction prospectively predict stress reactivity during the pandemic. Contrary to initial predictions, we found that a lower differential skin conductance response to CS+ and CS signals, particularly during anxiety extinctions measured pre-pandemic, was largely associated with increased stress reactivity during the pandemic across multiple measures. One possible explanation is that reduced stimulus discrimination, or the awareness to adequately distinguish between danger and safety signals, may result in greater overall threat and greater contextual anxiety. Further assessment of whether the fear-based model predicts the persistence of stress responses over time and with changing threats will provide valuable insights into the mechanisms underlying recovery. This information will form the basis for developing strategies to support and protect populations at risk from similar current and future crises.

Key words:Anxiety and PTSD, fear conditioning and extinction, COVID-19

To disclose:Nothing to disclose.

Mira Milad*, Zhenfu Wen, Isabel Moallem, Michelle Jeffers, Esther M. Blessing, Duna Abu-Amara, Amit Etkin, Mohammed R. Milad, Charles R. Marmar

New York University School of Medicine, New York, New York, United States

Background:Functional neuroimaging studies have previously reported dysfunctional activation and connectivity within cortical and subcortical structures in post-traumatic stress disorder (PTSD) and mild traumatic brain injury (mTBI). Aberrant neural activations within these circuits likely contribute to emotion dysregulation, a key pathology in both disorders. Implicit regulation of emotional conflict is an important component of emotion regulation that has not been fully studied in these disorders. Using fMRI data from 305 participants undergoing the emotional conflict task, we examined the neural correlates of emotional conflict detection and its implicit regulation in patients with PTSD, mTBI, and their comorbidity.

Methods:The 305 participants analyzed in this study included 50 with full or subthreshold PTSD, 93 with mTBI, 29 with full or subthreshold PTSD + mTBI, and 133 healthy controls. In the emotional conflict task, participants were asked to name the emotion expressed on a face while ignoring an underlying emotional word. Congruent trials were defined as trials in which the emotional facial expression (fear or joy) and the word (FEAR and HAPPY) match. Incongruent attempts were defined as attempts where the face and the word do not match. Two main contrasts were considered. One represented the detection of the presence or absence of conflict between the face and the word (incongruent vs. congruent trials). Another contrast was the assessment and regulation of conflicts (incongruent with prior process incongruent vs. incongruent with prior process congruent). Three analytical strategies were used. The first tested activations induced by grouping tasks in all participants. For this analysis, we used FWE correction at the voxel level across the whole brain. In the second set of analyses, we compared healthy controls with all diagnoses together. For the third set, we compared healthy controls with separate diagnoses (HC vs. PTSD, HC vs. TBI, HC vs. PTSD and PTSD+TBI, and HC vs. PTSD+TBI). For the second and third analyses, we used a whole-brain voxel-level threshold of p < 0.001 and a group-level FWE correction.

Results:In all participants, conflict detection resulted in robust activations in the dorsal anterior cingulate (dACC), thalamus, and bilateral insular cortex (IC). Absence of conflict-induced activations in the ventromedial prefrontal cortex, middle frontal cortex, and precuneus. Regulation of conflict-induced activations within the sensorimotor area, medial frontal gyrus, right IC, and precentral gyrus. For the second set of analyses, the diagnosed group showed significantly greater activation in the left hippocampus during conflict detection compared to the HC. The HC group showed higher activations within the dACC, precuneus, and thalamus during conflict assessment. No significant differences were observed between groups in conflict regulation. For the last set of analyses, we found no statistically significant differences between groups. Although no significant differences in activation within the amygdala and rostral anterior cingulate were detected in any of the analyzed contrasts, analyzes of functional connectivity seeding the hippocampus and dACC revealed significant connectivity to the amygdala and rACC in all contrasts.

Conclusions:When emotionally conflicting cues are encountered, our data suggest that multiple cortical and subcortical neural nodes are critical in processing sensory and emotional information to maintain emotional homeostasis. These regions include the thalamus, hippocampus, amygdala, precuneus, anterior cingulate, insular, ventral, and medial prefrontal cortex. A subset of these neural nodes showed dysregulated activations in participants with PTSD, mTBI, and PTSD + mTBI, suggesting aberrant recognition and conflict assessment. A surprising finding in the latest set of analyzes is the lack of meaningful results when comparing each diagnosis with healthy participants. This can be attributed to one of three possibilities: 1) the patient populations studied retain intact neural circuits for detecting and regulating emotional conflicts, 2) that the current neuroimaging task and/or tools are unable to detect subtle neural circuits. recognition and/or processing of emotional conflicts, or 3) insufficient strength. Given that we observed significant results when combining all diagnosed participants and given recent neuroimaging studies suggesting the need for approximately 100 subjects per group, we speculate that poor performance is the most likely explanation. Overall, however, our results replicate and confirm the role of multiple neural nodes in the implicit regulation of emotional conflict.

Key words:PTSD, conflict monitoring, TBI, functional magnetic resonance imaging (fMRI)

To disclose:Nothing to disclose.

Alexe Bilodeau-Houle, Catherine Raymond, Marie-France Marin*

University of Quebec at Montreal, Forschungszentrum des Montreal University Institute of Mental Health, Montreal, Canada

Background:Although most people are exposed to a potentially traumatic event at some point in their lives, only a significant minority will develop post-traumatic stress disorder (PTSD). Lifetime prevalence is estimated at 9% and affects twice as many women as men. Furthermore, this effect is particularly pronounced after puberty. In order to optimize prevention, detection and treatment plans, much research has been carried out to identify the psychological and biological factors that can make a person more susceptible to developing PTSD when faced with a traumatic event. At the psychological level, it is known that different personality traits can modulate the risk of developing pathology, such as anxiety and neuroticism. At the biological level, several systems have been studied, in particular the hypothalamic-pituitary-adrenal (HPA) axis, whose main end product is cortisol (an important stress hormone in humans). Most studies have shown lower cortisol levels in patients with PTSD. It was long thought that low HPA axis function was due to pathology, but recent evidence suggests that dysregulated cortisol patterns prior to trauma exposure are a risk factor for the development of pathology. In children, very few studies have examined the relationship between pre-trauma HPA axis function and the development of PTSD. Furthermore, the few studies carried out on this topic suggest hyperactivation of the HPA axis. Due to its unprecedented character, the recent COVID-19 pandemic has been an extremely stressful event that has caused great psychic suffering in the population. Furthermore, important individual differences were observed. Using a longitudinal design, we used the context of the pandemic to assess whether cortisol levels measured before and during the first few months of the first lockdown can predict PTSD symptoms in children and whether psychological characteristics can mitigate this effect.

Methods:92 children who had already participated in one of our laboratory experiments between 2017 and 2019 and were free of physical and mental health problems were contacted again in May 2020 to participate in this longitudinal study of mental distress during the pandemic. In June 2020 (Q1), 68 children (39 girls, 29 boys) aged 9-14 years provided a 6 cm hair sample, which was then divided into two 3 cm segments. These two hair segments allowed us to capture the cumulative levels of secreted cortisol 1) 3 months before the start of the first lockdown in Quebec, Canada (December 2019 to March 2020) and 2) during the first 3 months of the first lockdown (March 2020). 2020). 2020 to June 2020). From these two segments, we calculated the percentage change in cumulative cortisol levels between the onset and before the pandemic. At T1, children also completed the Big Five Questionnaire for Children (BFQ-C) to assess neuroticism. Post-traumatic stress symptoms were assessed four times every three months (June 2020-T1; September 2020-T2; December 2020-T3 and March 2021-T4) using the Revised Impact of Child Events Scale (CRIES). Because anxiety symptoms are highly correlated with posttraumatic stress symptoms, anxiety symptoms were also measured at each time point (T1 to T4) using the State-Tear Anxiety Inventory for Children (STAI-C; scale of State). Subsequently, state anxiety scores were added to the model as covariates.

Results:We performed a linear mixed-effects model that included time, neuroticism, and cumulative percent change in cortisol and their interactions as fixed effects. Gender and trait anxiety were used as covariates in the model. Analyzes revealed a significant interaction between time, neuroticism, and cumulative percent change in cortisol. In particular, a decrease in cortisol levels early in the pandemic was associated with increased PTSD symptoms in children with increased neuroticism at T1 and T2 (n = 67, F(3, 172) = 3.51, p = 0.017, R2m = 0.24, R2c = 0.59).

Conclusions:These results suggest that insufficient activation of the HPA axis during a stressful event, combined with high levels of neuroticism, may be a risk factor for the development of short-term post-traumatic stress symptoms in healthy children. This reinforces the importance of considering psychological and biological factors in the search for a better understanding of the pathology. Understanding predictors of psychological distress in healthy children when faced with a highly distressing chronic stressor could be instructive for early identification of vulnerable children in future crises.

Key words:Cortisol, COVID-19, children, post-traumatic stress symptoms, neuroticism

To disclose:Nothing to disclose.

Noor Nassar*, Zhenfu Wen, Mohammed Milad

New York University Grossman School of Medicine, Manhattan, New York, USA.

Background:Failure to adequately preserve extinct anxiety is a key feature of clinical anxiety. Therefore, exploring the neural correlates underlying conditioned fear extinction is crucial to advancing our understanding of the psychopathology of anxiety disorders. Early neuroimaging data show some connections between clinical symptoms and structural measures of various subcortical regions. However, the specific effects of frame size and the relationship between cortical thickness and changes in brain activation remain open to further investigation. Here, we performed a voxel-based morphometry (VBM) analysis to assess differences in gray matter volume (GMV) and associated brain activations during memory retrieval via fear erasure between healthy controls and patients with memory disorders. anxiety.

Methods:We analyzed structural images of 170 participants, including 75 controls and 95 with anxiety disorders, who underwent a two-day threat-and-extinction conditioning paradigm. VBM analysis was performed using the Computational Anatomy Toolbox (CAT12). First, we evaluated the main effect of group (HC vs. ANX) on GMV using voxel linear regression analysis with total intracranial volume, age, and gender as covariates. For regions that showed a significant group difference in GMV, we further examined whether the abnormal GMV of anxiety disorders correlates with brain activation during extinction memory retrieval. We examined GMV and brain activations of several regions of interest (ROIs) considered critical for threat detection and eradication, including the amygdala, hippocampus, insular cortex, dorsal anterior cingulate cortex (dACC), and ventromedial prefrontal cortex (vmPFC). An initial criterion of voxel level p <0.005 and a small volume family error correction (FWE) pFWE<0.05 were used to detect significant clustering. A whole brain analysis was also performed with a criterion of p < 0.001 at the voxel level and pFWE < 0.05 at the cluster level to identify significant brain regions.

Results:Decreased GMV in the anterior hippocampus (small volume correction pFWE < 0.05) and increased GMV in the right dorsolateral prefrontal cortex (dlPFC, total brain clustering level pFWE < 0.05) were found in patients with anxiety compared with healthy controls. Differences in GMV between control and anxiety disorders were associated with different brain activations during extinction memory retrieval. Specifically, in healthy controls, hippocampal volume was positively correlated with ventromedial prefrontal cortex (vmPFC) activation (small volume correction pFWE < 0.05), whereas in patients with anxiety disorders, hippocampal volume was negatively correlated with dACC activation (small pFWE volume correction). <0.05). In addition, dlPFC volume was positively correlated with activations of the dACC, precentral and postcentral gyrus, and supramarginal gyrus (total brain cluster level, all pFWE < 0.05) in healthy controls but not in patients with anxiety disorders.

Conclusions:The presented data suggest that differences in functional activations during extinction recovery may be associated with differences in GMV. There is a correspondence between the GMV of a region and the activation of a region it serves or interacts with. Thus, disturbances in the function of regions corresponding to absorbance retention (ie, vmPFC) could be due both to decreased cortical volumes in that region and to decreased activations in the region due to associations. GMV-dependent on another region (i.e. the hippocampus). 🇧🇷 The associations between GMV and extinction-related activation provide an additional layer of nuance to the impact of GMV on psychiatric psychopathology and therapeutic responses.

Key words:Gray matter volume, fMRI, fear, threat, anxiety disorders, functional and structural MRI

To disclose:Nothing to disclose.

Cecilia Hinojosa*, Courtney C. Haswell, C. Lexi Baird, Mohammed S.E. Sendi, Rajendra A. Morey, Sanne J.H. Von Rooy

Emory University School of Medicine, Atlanta, Georgia, USA

Background:Changes in the neurobiology of people with PTSD compared to controls were found in threat neurocircuitry, including the amygdala and hippocampus. Studies have observed abnormal resting-state functional connectivity (rs-HR) between regions underlying threat neurocircuitry, such as the prefrontal cortex, compared to controls. However, these studies were very small (n < 25) and larger sample sizes are needed for more unbiased analyses.

Methods:As part of the PGC-ENIGMA PTSD working group, seed-based resting-state fMRI data were centrally preprocessed using a standardized pipeline (HALFpipe) to N = 3007 and then visually quality checked. using the Three Independent Rater (CAH , CCH , SVR) Linux slicesdir command. Data were excluded from analysis for artifacts or weak signal (N = 387). Resting-state fMRI data from 22 donor sites were for N = 794 PTSD and N = 1092 controls for the right tonsil, N = 797 PTSD and N = 1097 controls for the left tonsil and N = 796 PTSD and N = 1096 controls for right and left hippocampus. Whole-brain seed-based analyzes were performed at the cluster level in the right and left amygdala and hippocampus using SPM12 with a p<0.005 and FWE-corrected cluster threshold.

Results:PTSD participants showed more positive rs-HR between the right amygdala and the subgenual ACC (sgACC; peak, MNI: x = -8, y = 14, z = -22; p < 0.001, k = 625) compared with controls, corrected FWE group level, p = 0.001) and similarly left amygdala and sgACC (peak, NIM: x = -8, y = 18, z = -22; p < 0.001, k = 286, level of corrected FWE group, p = 0.109).

Patients with PTSD had more positive rs-HR between right hippocampus and thalamus/brain stem compared to controls (peak, MNI: x = 6, y = -18, z = -14; p < 0.001, k = 555, AWE group ). corrected level, p = 0.002) and similar between left hippocampus and thalamus/brain stem (peak, MNI: x = 0, y = -24, z = -18; p < 0.001, k = 573, corrected FWE group plan, p = 0.002).

Conclusions:Using the largest centrally analyzed resting state dataset for PTSD to date, our results illustrate higher rs-HR between the amygdala and sgACC and between the hippocampus and thalamus in patients with PTSD compared to controls. Previous studies using smaller sample sizes and task-based designs related to rs-HR and threats have suggested a divergent functional relationship in PTSD participants in the amygdala and ventromedial prefrontal cortex (vmPFC) regions. Our preliminary results provide further evidence of the inappropriate regulatory relationship between these two regions using the largest study using resting data. In relation to our findings in the hippocampus, the increase in rs-HR between the hippocampus and the thalamus may contribute to altering threat processing in PTSD. These findings are important as they may help guide treatments that target these abnormal connections, such as B. Neuromodulation.

Key words:Functional connectivity at rest, post-traumatic stress disorder, amygdala, hippocampus

To disclose:Nothing to disclose.

Saren Seeley*, Zoe Schreiber, Maya Verghese, Tomasina Leska, Laurel Morris, Leah Cahn, Erno Hermans, Robert Pietrzak, M. Mercedes Perez-Rodriguez, Adriana Feder

Icahn School of Medicine at Mount Sinai, New York, New York, United States of America

Background:The ability to accurately "read" and respond to others is critical to developing and maintaining a supportive social network. People with post-traumatic stress disorder (PTSD) generally report little access to social support and greater difficulties with interpersonal relationships. Furthermore, recent neuroimaging findings suggest that deficits in social cognition may affect how people with PTSD perceive threat cues. However, few neuroimaging studies have examined social cognition in adults exposed to trauma in dimensions of resilience (ie, presence or absence of psychopathology) and level of exposure to the event. In this study, we sought to examine brain activation associated with social cognition during a mentalization task in symptomatic individuals with PTSD compared to less exposed and highly resilient controls. We hypothesized that the PTSD group would exhibit less BOLD activation related to social cognition in hypothetical areas of interest compared to less exposed and resistant control groups.

Methods:As part of a broader multimodal study on PTSD and resilience among World Trade Center (WTC) first responders, we recruited 74 adults who suffered the attacks of September 11, 2001 at the WTC and/or were in post-recovery September 11th. New York in 2001-2002. Stratified selection aimed to recruit participants into three groups: (1) PTSD (any number of WTC-related exposures; met all criteria for lifetime WTC-related PTSD as per the physician-administered PTSD Scale for the DSM -5 [CAPS -5] , with persistent clinically significant PTSD symptoms in the past month); (2) highly resistant (four or more WTC-related exposures associated with PTSD risk; no current or lifetime psychopathology); and (3) least exposed (three or fewer WTC exposures; no current or lifetime psychopathology). The target sample size in this ongoing study is N = 105 (CDC/NIOSH No. U01OH011473).

Participants participated in a neuroimaging session in which they performed a digitized version of the social cognition task "read the mind in the eyes". In each experiment, participants had to decide which of the two displayed words corresponded to a cropped photo of a person's face. The word pairs were either social (eg "anxious", "thoughtful") or non-social (eg "dark hair", "look left"). The contrast social > non-social represented the effect of social cognition rather than general perceptual and decision-making functions.

Pre-processing of the fMRI data used fMRIPrep 21.0.2 to generate individual motion, susceptibility distortion and time-division corrected echoes, which were further removed by TE-dependent independent component analysis (TEDANA 0.0.12) and finally smoothed . with FWHM Gaussian 4 mm core. Four of the 74 participants were excluded due to excessive exercise (n=3) or technical error (n=1), resulting in n=22 in the PTSD group, n=31 in the resistant group, and n=17 in the least exposed group.

Results:Linear models identified a main effect of test type (social versus non-social) on task performance: mean reaction time was slower (F=36.3, p<0.0001) and participants made more errors ( F=248.2, p<0.0001). social exams. There was no effect of core group on mean response time (F=1.49, p=0.22) or accuracy (F=2.85, p=0.064), or interaction with study type. For fMRI data, social > non-social contrast images were aggregated at the individual subject level for analysis at the group level. A 1-sample whole-brain t-test for the social > non-social effect identified clusters corresponding to a priori ROIs related to social cognition, including the medial prefrontal cortex, temporal poles, pars inferiori orbicularis gyrus, and cortex. anterior/posterior cingulate, using a threshold of pFWE = 0.05 and k = 50. There was a main group effect for the right temporal pole cluster (50 16 –32), F(2.67) = 3.98, r2 = 0.08, p = . 023.

Contrary to the hypothesis, the BOLD Social > Nonsocial signal was significantly higher in the right temporal pole group in the PTSD group compared to the resilient control (p = 0.027) and less exposed (p = 0.011) groups, while the control groups do not. differ significantly (p = 0.491). Continuous measurement of PTSD severity (last month CAPS5 scores) also predicted greater social > non-social activation of the right temporal pole, F(1.68) = 6.92, p = 0.01).

Conclusions:Our results are consistent with previous research implicating structural and functional differences in the right temporal pole in individuals with PTSD. They also provide additional support for social cognition as an emerging but important area for future studies of neural processes involved in psychological factors associated with risk or resilience after traumatic stressors.

Key words:PTSD, post-traumatic stress disorder, social cognition, functional magnetic resonance imaging (fMRI)

To disclose:Nothing to disclose.

Nicholas Balderston*, Marta Teferi, Lily Brown, Desmond Oathes, Yvette Sheline

University of Pennsylvania, Philadelphia, Pennsylvania, EE. UU.

Background:Repetitive transcranial magnetic stimulation (rTMS) is a promising way to develop new treatments for anxiety. Despite this promise, the main developmental pathway for anxiety has been the adaptation of protocols developed for the treatment of depression. Although these disorders are highly comorbid, the underlying neural mechanisms may differ, resulting in mixed efficacy in patients with anxiety. Consequently, there is a critical need for new neuromodulatory protocols that specifically target neural circuits affected by anxiety. Furthermore, such protocols need to be developed with dimensional measurements that reliably capture behavioral phenotypes related to network interruptions.

Methods:The purpose of this study is to provide preliminary evidence to determine the safety and efficacy of wall stimulation for anxiety. Current results come from an ongoing open pilot project targeting correct DPI in patients with generalized anxiety disorder (GAD). Patients received accelerated 1 Hz rTMS (5 days, 8 sessions/day, 600 pulses/session) at 100% motor threshold at rest for one week. Anxiety was measured at baseline and approximately 76 hours after rTMS using the unpredictable shock threat. Anxiety was quantified as increased startle during threat periods compared to safe periods (anxiety-potentiated startle; APS).

Results:At the time of writing this ongoing study, there were 5 patients enrolled with 3 grades. Using an intention-to-treat analysis, APS was reduced from before to after rTMS with a moderate effect size (Cohen's d = 0.51).

Conclusions:Although preliminary and qualitative, these results offer promising support for future studies on the treatment of GAD with parietal rTMS. These results are consistent with our previous work, showing that the IPS exhibits hyperarousal and hyperconnectivity in the face of unpredictable threats, and that reducing this hyperarousal with 1Hz stimulation can reduce anxiety as indicated by the APS. Along with this previous work, current results suggest that the IPS may be a key region for fear expression and an important target for inhibitory neuromodulation. Future clinical trials should replicate this work with appropriate blinding, appropriate control conditions, and a large enough sample size to ensure adequate statistical power (N > 70/group).

Key words:rTMS, generalized anxiety disorder, startle

To disclose:Nothing to disclose.

Isabel Moallem*, Zhenfu Wen, Mira Hammoud-Milad, Edward Pace-Schott, Mohammed Milad

NYU Langone, New York, New York, United States

Background:Associative learning theories suggest that the psychopathology of post-traumatic exposure may arise from dysfunctions in the neural circuits underlying threat conditioning and extinction learning. Related to threat and fear extinction, previous studies of post-traumatic stress disorder (PTSD) have consistently reported altered activations in regions of the medial prefrontal cortex, insular cortex, hippocampus, amygdala, and various parietal and temporal cortical regions. To the best of our knowledge, none of the studies to date have been able to assess the effects of different types of trauma exposure on the neurobiology of threat extinction and fear due to limited power. In this study, we combined data from 3 studies to examine whether the type of trauma (violent versus non-violent) differentially affects the neurobiology of threat conditioning and its subsequent extinction mechanisms.

Methods:We analyzed data from 207 trauma-exposed individuals with or without a diagnosis of PTSD who underwent 2-day threat conditioning, extinction learning, and extinction recall paradigm. We analyzed skin conductance response (SCR) and functional magnetic resonance imaging (fMRI) data. Reported traumatic events were classified as violent or non-violent. The violence category included experiencing or witnessing: combat, physical/sexual aggression or abuse, resulting in a total sample of n = 126 in this category; we refer to this group as the violent trauma (VTE) exposed group. The other 81 participants fell into the Nonviolent Trauma Exposed (NVTE) group. This category included experiencing or witnessing: accidental injuries, natural disasters, unexpected death. To further refine our analyzes in the VTE group, we divided this cohort into categories of sexual trauma (n = 55) versus non-sexual trauma (n = 71). For analysis of fMRI data, we first examined regions considered critical for conditioning and extinction, including the amygdala, hippocampus, insular cortex, ventromedial prefrontal cortex, and dorsal anterior cingulate cortex (small volume fix, family bug [AWE] fixed). 🇧🇷 For the whole brain analysis, we used a voxel level threshold of p<0.005 and pFWE<0.05 at the cluster level.

Results:In SCR analyses, the VTE group had significantly higher SCR for removed conditioned stimuli compared to the NVTE group (p < 0.01), indicating impaired extinction memory in the VTE group. No other statistically significant SCR differences were found between these two groups or within subgroup analyzes (all p > 0.10). In fMRI analyses, we observed significantly greater activations in posterior insular cortex and visual cortex (pFWE at cluster level < 0.05) during threat conditioning and significantly lower activations in dorsal anterior cingulate cortex, inferior parietal cortex and posterior insular cortex during the late period. phase extinction learning (pFWE < 0.05 at group level). Dysfunctional activations during late absorbance in the TEV group are consistent with impaired absorbance. Relative to the subanalyses focusing on sexual versus non-sexual VTE, the non-sexual VTE group showed greater activation in the rostral anterior cingulate cortex during initial conditioning (group level pFWE < 0.05) and higher activations in the inferior cortex. parietal islets and temporal cortices during extinction memory retrieval (pFWE < 0.05 at the cluster level).

Conclusions:We report results showing that participants who have experienced violent types of trauma demonstrate impaired fear erasure at the SCR level and dysfunctional activations in neural nodes responsible for attention and sensory processing of threat signals during threat acquisition and during extinction learning are important . We did not observe significant dysfunctional activations in neural circuits involved in threat sensing or emotion regulation (ie, amygdala, hippocampus) in any of our analyses, including the sexual versus nonsexual trauma groups. These null results suggest that, more often than not, violent trauma, whether sexual or otherwise, appears to have comparable effects on neural circuits for threat detection and emotion regulation. However, violent versus non-violent trauma appears to have a more differential impact on brain circuits related to attention and cognition.

Key words:PTSD, fMRI, trauma

To disclose:Nothing to disclose.

Cecilia Westbrook*, Michael Schlund, Greg Siegle, Jennifer Silk, Neal Ryan, Erika Forbes, Dana McMakin, Philip Kendall, Anthony Mannarino, Cecile Ladouceur

University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA

Background:Cognitive behavioral therapy (CBT) is a gold standard intervention for pediatric anxiety disorders. Part of its effectiveness stems from exposure therapy, in which children approach feared stimuli and learn to gradually reduce their fear. Despite the clinical history, between 20% and 40% of patients do not respond to CBT (Kendall & Peterman, 2015), which can be explained in part by the lower motivation to approach necessary to face the feared stimuli. The purpose of this study was to examine the neural correlates of treatment success for CBT using data from a previously published RCT (Silk et al., 2018) that compared treating adolescents with anxiety disorders with CBT versus active therapy control, centered therapy in children (CCT), including comparison with adolescents without psychiatric diagnosis (CPT). We examined data from an fMRI Focus-Avoid Conflict task (Schlund et al., 2010) and hypothesized that anxious adolescents would demonstrate greater avoidance activity compared to NPD, but treatment responders have greater approximation and focus. Avoid conflict activities in the first place. Regions of interest included the ventral and dorsal striatum, amygdala, dorsal ACC, and anterior insula.

Methods:A total of 97 adolescents with generalized social separation anxiety disorder (SANX), 9 to 14 years of age, were randomized in a 2:1 ratio to CBT (N=67) or CCT (N=30) and had usable image data; 38 age- and gender-matched NPD youth also had usable data. The adolescent underwent an initial assessment using a standardized DSM-IV diagnostic interview (K-SADS-PL) and a measure of anxiety severity (Pediatric Anxiety Rating Scale (PARS)), followed by an initial magnetic field magnetic resonance imaging and then 16 CBT sessions. or CCT therapy before reassessment and MRI Response to treatment was defined as a reduction in PARS score of 35% or more MRI data were preprocessed with fmriprep (https://fmriprep.org/es/estable/) and analyzed with FSL (https://fsl.fmrib.ox.ac.uk/fsl/fslwiki🇧🇷 Multiple comparison correction was performed using cluster-based random field theory with a cluster threshold of z = 3.1 and a cluster-corrected p-value threshold of 0.05. All analyzes controlled for age and sex.

Results:Most ANX adolescents (N = 67) responded to treatment. Contrary to our hypotheses, there were no differences in conflict-related focus, avoidance, or focus-avoidance brain activity between anxious and NPD adolescents, nor did activity predict response to treatment, either at baseline or with changes in behavior. brain activity before and after treatment. treatment. However, when we examined the interaction between the therapy group and treatment response, there were significant activations for the attachment condition in the bilateral dorsolateral and medial PFC, right dorsal striatum, bilateral precuneus/posterior cingulate, bilateral posterior insula, parietal inferior, superior temporal and occipital cortices. For the avoidance contrast, the interaction term produced activations in bilateral dlPFC, bilateral vlPFC, left amygdala, left ventral and dorsal striatum, bilateral superior and inferior parietal cortex, bilateral temporal cortex and occipital cortex. Visualization of these interactions showed that treatment non-response in the CBT group corresponded to a decrease in approach avoidance activity, whereas treatment response corresponded to an increase or no change in activity. The CCT group showed the opposite pattern, such that non-response to treatment corresponded to an increase in activity, while response to treatment corresponded to a decrease or no change in activity.

Conclusions:Although most adolescents with ANX responded to treatment, patterns of change in neural activity differed between types of treatment, suggesting that mechanisms of treatment efficacy may be unique to CBT. A change in brain activity associated with approach and avoidance motivation, both within and outside defined areas of interest, indicates that both neural systems are relevant to the treatment of adolescent anxiety, but are activated differently in adolescents. treatment. Go.

Key words:Adolescent anxiety, fMRI task, focus/avoidance, cognitive behavioral therapy, RCTs

To disclose:Nothing to disclose.

Timothy McDermott*, Tsuchiyagaito Aki, Ramirez Sam, Mallory Cannon, James Touthang, Masaya Misaki, Robin Aupperle

Laureate Institute for Brain Research, Tulsa, Oklahoma, EUA.

Background:Real-time functional magnetic resonance imaging (rt-fMRI-nf) neurofeedback is an endogenous neuromodulation approach in which individuals self-regulate their own neural activity in the moment using strategies related to a specific construct of interest. Cognitive control deficits in an emotional context negatively affect people with mental disorders, including those with depression, anxiety and PTSD. The left dorsolateral prefrontal cortex (dlPFC) has been shown to be a key region to facilitate cognitive-emotional control. Using a double-blind, randomized, controlled study design, this study tested a novel rt-fMRI-nf protocol designed to increase blood oxygen level-dependent activity of the left dlPFC during cognitive-emotional monitoring and self-report and behavioral measures to improve cognitive-emotional control. 🇧🇷

Methods:Healthy adult participants (N = 70; 42 women; mean age = 31.2 years) participated in the study and were randomized to active (n = 37; left dlPFC) or sham (n = 33; left postcentral gyrus) Single session MRI mapped -nf (clinictrials.gov identifier: NCT04543513). Feedback was provided from a 7 mm spherical region of interest centered on coordinates in the left dlPFC and the left postcentral gyrus, respectively. During neurofeedback, participants focused on executive functional tasks (eg, mental arithmetic, word list recall, to-do list practice) while being presented with negative emotional words that were distracting and required emotional cognitive control. Single-session neurofeedback consisted of five runs of rt-fMRI-nf starting with practice, followed by three training runs, and finally a transfer run with no feedback. Participants also completed a self-report [Patient-Reported Outcomes Measurement Information System (PROMIS): Self-Efficacy for Managing Emotions] and behavioral measures [Emotional Stroop Task (EST) Interference Effect] of emotional cognitive control prior to rt-fMRI-nf and in one-day aftercare. The primary outcome was dlPFC activity during neurofeedback and the secondary outcomes were self-report/behavioral measures of cognitive-emotional control. A series of linear mixed-effects (SML) models were performed to investigate whether active nf-rt-fMRI produced greater changes for each endpoint compared to sham [fixed effects: group, time, group interaction; Random Effect: Subject ID]. We also assessed protocol tolerability and subjective emotional distress associated with negative words using a post-neurofeedback survey with scores from 1 to 10.

Results:SCIs showed a significant group interaction in left dlPFC activity (p = 0.031; η2 = 0.021), and this interaction was such that active neurofeedback resulted in increased left dlPFC activity in run 1 (p = 0.030; d = 0 .66) and in run 2 (p = 0.042; d = 0.62), but neither for run 3 (p = 0.82) nor for the transfer run (p = 0.30). LMEs showed no significant effects on self-report or behavioral measures of cognitive-emotional control (p's > 0.46). Note that these self-reported/behavioral measures were significantly inversely correlated with each other (p < .001; r = -.41), suggesting that those with higher scores on the PROMIS: Self-Efficacy in Managing Emotions had a lower emotional impact in EST displayed. Participants with different medical conditions described the protocol as tolerable with minimal distress and were unable to identify their nf-rtfMRI condition (p = .83). Although the overall level of emotional distress reported in response to negative words displayed during neurofeedback was quite low in both groups (M = 1.57 on a scale of 1 to 10), participants in the active group compared with exposure significantly smaller. smallest (M = 1.32). for the sham group (M = 1.84; p = 0.039; d = -.51).

Conclusions:These results support the feasibility of rt-fMRI-nf left dlPFC and identify potentially acute effects on left dlPFC activity and subjective emotional distress. However, the overall results indicate that rt-fMRI-nf had an initial but not sustained effect on left dlPFC activity and therefore represents complexities and nuances involved in using rt-fMRI-nf to modulate neuronal activity and improve psychological function. The sustained effect of the current dlPFC neurofeedback protocol may have been limited by participant fatigue associated with a long protocol, individual variability in left dlPFC architecture, and decreased challenge of cognitive tasks over time. Future studies are needed to optimize the cognitive strategies used, the purpose of dlPFC, and the timing and duration of the neurofeedback protocol, as well as to determine whether dlPFC neurofeedback can have differential effects in clinical populations.

Key words:Non-invasive neuromodulation, functional magnetic resonance imaging (fMRI), fMRI negative affective stimuli, cognitive enhancement, real-time fMRI neurofeedback

To disclose:Nothing to disclose.

Hannah Berg*, Timothy McDermott, Elisabeth Akeman, Jessica Santiago, James Touthang, Kelly Cosgrove, Mallory Cannon, Ashley Clausen, Namik Kirlic, Ryan Smith, Christopher Martell, Kate Wolitzky-Taylor, Michelle Craske, James Abelson, Jerzy Bodurka, Martin Paulus , Robin Aupperle

Laureate Institute for Brain Research, Tulsa, Oklahoma, EUA.

Background:People with anxiety disorders often make maladaptive decisions when faced with focus-avoidance conflict (AAC), a behavior pattern addressed in exposure-based therapy (EXP) and behavioral activation (BA). Identifying the mechanisms by which these treatments promote adaptive behavior can guide the development of process-specific treatment approaches. In the present study, we examined neural and behavioral responses to AAC before and after BA and EXP in a sample of adults with generalized anxiety disorder (GAD).

Methods:Participants were randomized to complete 10 weekly BA or EXP sessions. Symptoms were assessed before treatment, at each treatment session, and after treatment using the GAD-7, PROMIS Anxiety, and PROMIS Depression scales. Persons who completed at least 7 out of 10 therapy sessions were considered to have completed treatment and were included in clinical outcome analyses. Treatment completion and treatment response, defined as at least a 30% reduction in GAD-7 scores before and after treatment, were compared between treatment arms using logistic regressions. Mixed-effects linear regressions were performed for symptom scores, with time (all time points) and treatment arm (BA, EXP) entered as predictors.

Before and after treatment, participants completed an AAC task during fMRI. In the task, participants chose how close to approach or avoid based on explicit cues that show the most likely outcomes associated with each position along a horizontal trail on the screen. On each trial, a decision on approach may lead to an aversive outcome (negatively rated sights and sounds), a desirable outcome (earning 2, 4 or 6 pence) or both (ie a UK trial). Treatment graduates who completed the UK task before and after treatment and had usable fMRI data were included in analyzes of behavior and brain activity during the UK task. We performed mixed-effects linear regressions for the effects of time (before, after treatment), treatment arm, and study type (2-, 4-, or 6-cent conflict) on lane position and response time across all CAA studies. Computational parameters reflecting emotional conflict (ie, threat aversion over rewards) and decision uncertainty, which were previously found to be increased in anxious individuals, were extracted from approach and avoidance behaviors. , and we performed mixed-effects linear regressions between the Time effects. and treatment arm on these parameters. Next, neural responses (Blood Oxygen Level Dependent Signal [BOLD]) were extracted for regions of a priori interest, including the dorsolateral prefrontal cortex (dlPFC), amygdala, anterior cingulate, anterior insula, and striatal responses to decision phase; and striatal responses to image presentation and reward receipt. We performed linear mixed-effects regressions for each region of interest with time, treatment arm, and study type (aversive, palatable, conflicting 2, 4, or 6 cents) as predictors and neural responses as outcome variables. Age, gender, and education were included as covariates in all group-level regressions.

Results:Of the 102 study participants, 70 completed treatment (38 BA, 32 EXP), reflecting comparable completion across treatment arms (p = 0.127). Most treatment finishers responded to treatment in BA (66%) and EXP (59%) with comparable responses across all treatment groups (p = 0.761). Effect sizes on GAD-7 scores before and after treatment were large for BA (d=-1.14) and EXP (d=-0.97). Pre- and post-treatment contrasts did not differ between treatments for GAD-7 scores (p = 0.540), but did between treatments for PROMIS anxiety (p = 0.039, d = 0.13) and depression scores. PROMIS (p = 0.029, d = .14), which reflects a greater improvement in symptoms with BA compared to EXP in both cases.

Forty-nine participants (29 BA, 20 EXP) were included in the behavioral and fMRI analysis. After both treatments, reaction times (p = 0.008, ηp2 = 0.03) and unexpectedly also approach behavior (p = 0.048; ηp2 = 0.02) in AAC studies were reduced. The computational parameter that reflects emotional conflict increased after treatments (p = 0.017, ηp2 = 0.12); the decision uncertainty parameter did not change significantly after treatments (p = 0.162). Analyzes of neural responses showed that BA rather than EXP was associated with greater involvement of the left dlPFC during decision-making (time after interaction between treatment arms: p = 0.020; ηp2 = 0.01), and both treatments were associated with increased striatal response associated with imaging results (p = 0.037, ηp2 = 0.03) and monetary reward (p = 0.015, ηp2 = 0.04).

Conclusions:BA and EXP have been shown to be effective treatments for GAD. Increased left dlPFC activation during decision making and increased striatal engagement during emotionally impactful outcomes may reflect the neural basis of a process by which BA and EXP influence decision making in approach and avoidance conflicts. One interpretation is that people in treatment increase dlPFC-mediated laborious deliberation during UK decision-making and striatal-mediated encoding of salient outcomes in real-world tasks and settings. Increases in left dlPFC activity were particularly robust in BA, possibly due to BA's focus on conscious engagement in values-based behavior. More research is needed to examine whether psychological treatments can be optimized by focusing on specific decision-making processes.

Key words:Anxiety, Generalized Anxiety Disorder, fMRI, Decision Making, Focus-Avoidance Conflict

To disclose:Nothing to disclose.

Nakul Aggarwal*, Do Tromp, Daniel Pine, Lisa Williams, Ned Kalin

University of Wisconsin - Madison, Madison, Wisconsin, United States

Background:Anxiety disorders (AD) appear in childhood and early adolescence and are among the most common psychiatric disorders. At the onset of puberty, women are twice as likely to have AD as men. Extensive research has implicated changes in the white matter (WM) microstructure of the prefrontal limbic pathways, as well as in other regions of the WM in the pathophysiology of ADs. These results are interesting because the WM consists mainly of myelinated axons and myelin plays an important role in mediating optimal neuronal communication. However, few studies have examined anxiety-related changes in WM in adolescence and in relation to gender. To further investigate associations between childhood ADs, WM microstructural integrity, and gender, we analyzed diffusion tensor imaging (DTI) data from 295 preadolescent adolescents with and without AD.

Methods:Prepubertal adolescents with AD (social, generalized, and/or separation AD) and healthy controls were enrolled between 8 and 12 years of age at 2 study centers (UW-Madison, NIMH) and underwent a DTI scan at a 3T scanner. The final sample (n = 295; 201 women) included 163 children with AD and 132 controls. Analyzes based on tractograms and voxels examined the main effect of ADs, as well as the interaction of AD by sex for the WM metrics [fractional anisotropy (FA), radial diffusivity (RD), mean diffusivity (MD) and axial diffusivity (XD)] in seven bilateral tracts of interest and in whole-brain MW.

Results:Results showed widespread anxiety-related changes in DTI metrics across multiple WM regions. Crucially, anxiety-related effects showed significant interaction with gender, such that AD-related PA reductions and RD increases were observed exclusively in boys and not in girls. Prepubertal children with AD showed decreased AF and increased RD in different regions of MO across the brain, associated (UF, EC, IFO, SLF, ST, ILF) compared to healthy control children (P- FWE <0.05), commissural (CC), projection (CR, IC) and brainstem (CST, CP, ML), while no group differences were observed in girls.

Conclusions:"This study represents the largest cross-sectional DTI study of childhood anxiety to date. The results show that childhood ADs are associated with pervasive changes in WM microarchitecture throughout the brain, and more importantly, this relationship is only evident in children." These results, particularly the combination of reduced AF and increased DR, point to the possibility that WM microstructure and myelination processes may be related to the underlying pathophysiology of childhood ADs and lay the groundwork for future work. WM as a treatment target. for new therapies.

Key words:Childhood anxiety, white matter microstructure, diffusion tensor imaging (DTI), myelination, gender differences

To disclose:Nothing to disclose.

Andrew James*, Allison Kuehn, Clinton Kilts

Arkansas University of Medical Sciences, Little Rock, Arkansas, USA

Background:Historically, neuroimaging studies in psychiatry have attempted to identify the neurobiological mechanisms that put people at risk for developing psychiatric disorders. However, there has been growing interest in identifying neurobiological mechanisms that promote psychological resilience, a MeSH term (D055500) defined in 2009 as "The human capacity for resilience in the face of tragedy, trauma, adversity, hardship, and adaptation". significant. to life stressors. To address this growing interest, we performed a systematic review and meta-analysis of neuroimaging of brain regions that may promote mental resilience.

Methods:We performed a systematic review of 4 bibliographic databases (PubMed, Embase, PsychInfo, and Web of Science) for journal articles containing the keyword "resilience" and a functional neuroimaging technique. (See poster for specific and precise database searches.) These searches returned 498 unique articles. 429 articles were excluded for reasons including a non-psychological definition of resilience (eg, cognitive resilience after neurosurgery), failure to recruit a resilient sample, and failure to provide neuroimaging data or coordinates, resulting in As a result, 69 relevant articles were included for the analysis. This search also returned 42 review articles whose bibliographies were searched for relevant articles: these articles included an additional 2205 articles, of which 78 met the inclusion criteria, for 69 + 78 = 147 unique articles. All systematic review items, including reasons for exclusion, sample size, and brain coordinates, were stored in the non-proprietary reference manager Zotero for accuracy and reproducibility. Custom Python code extracted the ROI coordinates of items in the Talairach or MNI atlas space for the GingerALE Activation Probability Estimation (ALE) meta-analysis. The 147 studies identified 499 outbreaks that were significantly more associated with resilient groups than healthy controls and/or patient groups. GingerALE was performed with uncorrected p = 0.001 and 100 permutations for FWE p = 0.01. All codes available on request.

Results:The ALE meta-analysis associated three regions with psychological resilience: right amygdala (ALE = 0.060, Z = 7.76), right amygdala (ALE = 0.056, Z = 7.41) and dorsal anterior cingulate (ALE = 0.032, Z = 5). .04). Post hoc review of the studies contributing to each region found that the amygdala consisted primarily of PTSD studies (~45%) and depression (~30%), while the anterior cingulate primarily consisted of PTSD studies (38%) and had schizophrenia (38%).

Conclusions:The amygdala and anterior cingulate play critical roles in several cognitions, including threat detection, error detection, and emotion regulation. In particular, amygdala and anterior cingulate hyperactivity has been associated with PTSD and MDD. Our results suggest that these regions play a more complex role in promoting risk and resilience to psychiatric disorders than previously thought. Future work will attempt to identify disorder-specific risk and/or resilience predictors.

Key words:Risk and resilience, human neuroimaging, emotional regulation

To disclose:Nothing to disclose.

Anthony King*, Chandra Sripada, Israel Liberzon, K. Luan Phan

Ohio State University, Columbus, Ohio, USA. UU.

Background:Post-traumatic stress disorder (PTSD) is widespread, can be chronic and debilitating, and has a high human and economic cost to individuals, families, and society. Although existing trauma-based psychotherapies show high efficacy, many PTSD patients reject trauma-focused therapy, and meta-analyses report that 30-50% of PTSD patients treated with trauma-focused therapy do not show clinically significant improvement, suggesting that "one size may not fit all". Evidence is accumulating for the clinically significant effectiveness of 8-week cluster mindfulness-based approaches such as mindfulness-based cognitive therapy (MBCT) for acute depression, anxiety, and PTSD, beyond the original goal of relapse prevention for depression and use of disorder substances. , whose additional research supports efficacy in PTSD and possible neural mechanisms. In 2016, we reported that a mindfulness-based intervention in PTSD resulted in increased resting-state functional connectivity (rsFC) between the posterior cingulate cortex (PCC, default mode network key node, DMN) and the prefrontal cortex. . dorsolateral (dlPFC, key frontoparietal network node) led , FPN); and the increase in PCC-dlPFC rsFC associated with mindfulness was independently replicated by 3 labs. In 2017, we filed hypotheses at the NCCIH (R61 “Go Criteria”) that MBCT, compared to an active mind-body comparator, progressive muscle relaxation (PMR), would result in increased PCC-dlPFC rsFC, and both MBCT and PMR lead to a decrease in PCC-insular rsFC (which is increased in PTSD).

Methods:We conducted a randomized controlled trial (RCT) in patients with PTSD that compared MBCT with active mind-body control (PMR, structurally similar to MBCT but without mindfulness education) using cluster randomization (allocation blindness during recruitment). Functional magnetic resonance imaging (3T GE scanner) was performed on admission and within 3 weeks of treatment. We accepted 161 people from the community and recruited 77 with a CAPS-5 diagnosis of PTSD and functional magnetic resonance imaging. Due to the COVID pandemic, 22 patients were lost to follow-up and interventions were changed to remote ("Zoom") treatment, and 41 participants completed RCT with fMRI scans before and after therapy. The evaluations (CAPS-5 and HAM-D) were performed by blinded evaluators and the CGIs were obtained by consensus of the clinical team, with the PI and the analysts being blinded. Self-report measures (PCL-5, decentration, PTSD detection, rumination, etc.) were performed using the web-based REDCap. fMRI paradigms including resting state (8 min), a previously validated self-referential task, and a contextual processing task. We evaluated rsFC using a PCC seed in the CONN toolbox and used a flexible ANOVA in SPM12 to test a time interaction term (before vs. after therapy) after treatment (MBCT vs. PMR).

Results:We report results from our rsFC data that support our reported hypotheses that MBCT leads to an increase in PCC-dlPFC and a decrease in PCC-insular rsFC. Both MBCT and PMR resulted in clinically significant improvements in PTSD (median MBCT 8.9 CAPS-5 point reduction, Hedges g =1.0, p<0.001, PMR 10.1 CAPS-5 point reduction, g = 1, 0, p<0.001), not significant between treatment effect. Both interventions were well tolerated and had completion rates (5+ sessions) >80%, "response" rates (CGI-I 1: very much or 2: very much improvement) were 48% MBCT and 50% PMR. In the ANOVA Z interaction map of the rsFC seed of the PCC, we found a cluster on the right dlPFC/ BA 10 MINI: (30, 48, 12), F = 20.91, Z = 3.90, k = 94 voxels, SVC pFWE = 0.021. Testing for change score (pre-vs. post-delta) in beta dlPFC values ​​(5 mm bead) revealed a significantly greater increase (p = 0.002) in rsFC in the MBCT group compared to the PMR - Group (g Coverage = 1.03). Furthermore, the change in PCC-dlPFC rsFC was greater in MBCT responders than non-responders (p < 0.05, g = 0.57). Both MBCT and PMR resulted in reduced PCC-insular rsFC (before vs. after eel insula removal g = -0.35 in MBCT, g = -0.53 in PMR, p < .05).

Conclusions:We found evidence supporting our proprietary hypothesis (R61 “Go Criteria”) that MBCT, but not PMR, results in an increase in PCC-dlPFC rsFC (DMN-FPN Altered Network Connectivity). This is also consistent with recently published results by independent research groups. Furthermore, the increase in PCC-dlPFC rsFC was significantly associated with clinical improvement (CGI-I scores blinded to PTSD) in the MBCT group only. These data support PCC-dlPFC FC as a possible targeted treatment mechanism for mindfulness interventions potentially related to increased volitional metacognitive attention and emotional regulation of spontaneous distressing thoughts. Both MBCT and PMR decreased PCC-insular rsFC, suggesting a general mechanism related to improvement in PTSD symptoms.

Key words:Achtsamkeit, PTBS, Default Mode Network (DMN), Frontoparietal Network, Insula Connectivity

To disclose:Nothing to disclose.

Zhenfu Wen*, Jörgen Rosén, Fredrik Åhs, Sara Lazar, Edward Pace-Schott, Elizabeth Phelps, Joseph LeDoux, Mohammed Milad

New York University, New York, New York, United States

Background:Threat conditioning and extinction is one of the most important translational models for understanding anxiety and trauma-related psychopathology. The "threat circuit," which primarily includes the medial prefrontal cortex, insular cortex, hippocampus, and amygdala, is believed to play a key role in detecting and removing threats. However, recent findings indicate that the processing of threatening and fearful stimuli is highly distributed across multiple neural systems. In this study, we combine fMRI data and machine learning methods to identify and validate distributed neural representations of stimuli that encode threats or security. We then use external datasets from various paradigms to test the specificity of the newly identified circuit.

Methods:Task-based fMRI data from a total of 1455 participants were analyzed in the present study. We use neural activations inside and outside the "threat network" to distinguish conditioned stimuli associated with threat (CS+) or security (CS-) in experimental stages of threat conditioning and extinction. We evaluated the performance of the decoding models by cross-validation on a discovery dataset (n = 420) and tested the generalization of the models with two external datasets (n = 126 and 94). We then estimated the predictive weight of each voxel and identified brain regions that contributed significantly to the decoding of CS +  and CS-. We validated a new circuit by applying the trained decoding models with their neural activations to various external datasets using other paradigms (n=815 across 7 datasets). Permutation tests were used to assess the significance of decoding precisions.

Results:The neural signal within the "threat network" successfully decoded the representations induced by conditioned stimuli in the discovery dataset (accuracy 62.6 ~ 75.2%) and generalized to the two outer datasets (dataset 1 : 58.3% ~ 70.8%, data set 2: 58.7% ~ 82.7%). Importantly, sorting performances were significantly improved by distributed network activations (discovery dataset: 72.6% to 88.6%, external dataset 1: 66.7% to 80.2%, data external 2: 60.3% to 90.6%). Results from the distributed network that contributed significantly to the decoder included somatomotor regions, prefrontal and parietal regions, thalamus, cerebellum, and caudate. All regions that contributed significantly to the CS +  and CS- rating (including the threat cycle) formed an updated cycle that we called the “fear homeostasis cycle”. These regions consistently coded CS + /CS- across experimental phases or dynamically changed their preference to CS + /CS- depending on the experimental phase. Classifiers trained by neural patterns of the newly defined circuitry were successfully applied to three visual threat conditioning datasets using different paradigms (n = 299, 94 and 48, highest accuracy: 91.0%, 91.0%, 87 .5%), an auditory threat conditioning dataset (n=68, highest accuracy: 83.8%) and a dataset examining subjectively reported anxiety (n=65, highest accuracy: 81.5%). ). Applying classifiers to brain activations related to neural representations unrelated to associative learning and memory (but still related to emotional stimuli) resulted in reduced precisions: image-evoked negative affect (n = 182, maximum precision: 75.3%) , physical pain (n = 59, highest accuracy: 71.2%) and social rejection (n = 59, highest accuracy: 61.0%).

Conclusions:By optimizing the classifiers on a large fMRI dataset, we were able to show that conditioned stimuli can be classified using "threat network" neural activations and that better performance can be achieved when using neural activations from widely distributed neural networks. Based on these results, we updated the "anxiety homeostasis circuitry" by expanding the "threat circuitry" to include other brain regions important in processing threat and fear. The analysis of the external datasets showed a strong generalizability of the decoder in different experimental setups, locations and scanners with different acquisition parameters. And finally, the sensitivity and specificity of the "fear homeostasis circuitry" was verified in the representation of threat conditioning, fear and emotionally salient cues.

Key words:Multivariate pattern analysis, fear conditioning and extinction, classification, generalization

To disclose:Nothing to disclose.

Adam Gorka*, Christian Grillon, Monique Ernst

National Institute of Mental Health, Bethesda, Maryland, USA.

Background:Patients diagnosed with clinical anxiety disorders are more sensitive to threatening information and have altered cognitive processing. However, it is currently unclear whether threatening information influences similar or different computational processes in healthy participants and patients with clinical anxiety disorders. Previous research has shown that experimental models of fear (eg, triggered by an unpredictable collision threat) serve to facilitate performance during the go/no-go paradigm. Our aim was to determine how clinical anxiety disorders and a history of panic attacks affect drift-diffusion model parameters underlying cognitive processing during experimental anxiety.

Methods:Thirty-nine healthy participants and 42 anxious patients, 14 of whom had a history of panic attacks, performed the go/no-go paradigm during periods of security and periods of induced anxiety. Induced anxiety facilitated performance during unsuccessful tests, regardless of clinical diagnosis.

Results:Our computer analysis showed that fear induced significantly reduced the boundary separation parameter. Within the anxious patient group, the impact of anxiety-induced 'boundary separation' was significantly attenuated by a history of panic attacks.

Conclusions:Boundary gap corresponds to the amount of information needed to trigger a decision, and our results may reflect more cautious decision-making during threat exposure in anxious patients with a history of panic attacks. Taken together, our results suggest that computational models can help us understand the mechanisms by which experimental models of anxiety affect cognitive processes in clinical patients.

Key words:Anxiety, Computational cognitive neuroscience, Panic attacks

To disclose:Nothing to disclose.

Nicholas Petrosino*, Amin Zandvakili, Jennifer Barredo, Noelle Marcotullio, Noah Philip

Brown University e VA Providence, Providence, Rhode Island, EE. UU.

Background:Post-traumatic stress disorder (PTSD) is debilitating, difficult to diagnose and often resistant to treatment. Functional imaging has the potential to provide a deeper understanding of the neurobiology of PTSD. However, this data is inherently complex and it is difficult to find a comprehensible approach. Here, we adopted a network visualization algorithm called Multidimensional Scaling (MDS) that scales down high-dimensional data while preserving paired distances to visualize functional connectivity networks and assess connectivity changes related to PTSD severity.

Methods:We performed resting-state fMRI on a sample of n = 50 patients with PTSD. Pair-to-pair functional connectivity maps were calculated using 100 relevant regions of interest. Participants were divided into two groups: those with PTSD symptoms of high or low severity, using an average breakdown of total scores on the DSM-5 PTSD Checklist (PCL-5). Pearson's cross-correlation values ​​for the regional pairs that make up the maps were transformed into differences and a sparse area of ​​data was generated by a negative exponential transformation. The MDS was then executed, incorporating the 4950 regional connectivity pairs into a two-dimensional space. Permutation tests (500 MDS iterations on randomly shuffled data) were used to determine which regions differed significantly in connectivity between groups. The experiment was repeated for the PTSD symptom groups of intrusion, avoidance, cognition/mood, and arousal based on the median divisions of the respective PCL-5 subscale scores.

Results:The median PCL-5 total score for our sample fell in the moderate range of severity (median = 46.5; 95% CI 24-71), and the PCL-5 total and subscale scores were highly and significantly correlated (coefficients Pearson's correlation in the range of 0.38 to 0.81). For overall PTSD severity, three regions showed significant differences in cluster connectivity: left dorsolateral prefrontal cortex (DLPFC) and right ventrolateral prefrontal cortex (both frontoparietal nodes) and left anterior paracingulate (pont) (p = 0.021 , 0.044 and <0.002, respectively). Analyzes of PTSD symptom groups also revealed significant connectivity differences between the high and low severity groups. Nine regions were significant for the intrusion group: the left thalamus, the DLPFC bilaterally, the ventromedial prefrontal cortex bilaterally, the right orbital cortex, the right middle cingulate/paraculate of the frontoparietal network, and the left striatum and cingulate/paraculate. anterior right in the standard mode network (p = 0.009, 0.040 [left], 0.025 [right], 0.005 [left], 0.003 [right], 0.033, 0.035, 0.042 and 0.034, respectively). The avoidance group showed differences in the right basolateral amygdala, as well as in the left orbital cortex and left medial prefrontal cortex in the default mode network (p = 0.029, 0.041 and 0.035, respectively). Connections to several other relevant network nodes also showed significant differences for the cognition/mood and arousal symptom groups.

Conclusions:We successfully introduced a network analysis tool to a new application of functional imaging data, which revealed associations of overall PTSD and cluster severity with connectivity to and from many relevant network nodes, with the strongest results in the intrusion cluster . This offers new insights into computational and functional modeling of PTSD severity that may help guide objective diagnosis and treatment in the future.

Key words:Post Traumatic Stress Disorder, Functional Connectivity at Rest, Computational Psychiatry

To disclose:Nothing to disclose.

Vanessa Brown*, Timothy Allen, Laura Taglioni, Rebecca Price, Alexandre Dombrovski

University of Pittsburgh, Pittsburgh, Pennsylvania, USA

Background:Difficulty learning and responding to uncertain threats is a central impediment in anxiety (Grupe & Nitschke, 2013). Neurocomputational modeling may refute competing hypotheses about the sources of anxiety-uncertainty learning disorders (Brown et al., 2021; Montague et al., 2012; Pulcu & Browning, 2019). In particular, different forms of computationally derived uncertainty (from noise versus changepoints to stimulus outcome contingencies) have different neural substrates and implications for learning (Mackintosh, 1975; Nassar et al., 2018; Pearce and Hall, 1980; Piray and Daw, 2021; Yu and Dayan, 2005).

Even with models, it can be methodologically difficult to measure these types of uncertainty simultaneously; As a result, it is unknown how clinically anxious people are affected by learning about uncertainty. It is also unclear whether impaired uncertainty learning is related to the somatic symptoms and hyperarousal present in anxiety-based disorders (Craske et al., 2009; McTeague & Lang, 2012; Watson, 2005) or more generally shared by internalization-based disorders. . stress.

In the current study, we develop a new task and a computational learning model to measure learning about uncertainty. We examine the relationships between behavioral indices based on models of uncertain learning and measures of anxiety and stress to understand how anxiety disrupts uncertain learning.

Methods:Data collection is in progress; Preliminary results of 40 participants are reported (mean age [SD]: 32.3 [9.7]; gender # [%]: 29 [73%] female, 10 [25%] male, 1 [2.5%] ] nonbinary; Race # [%]: 29 [73%] White, 7 [17.5%] Black, 1 [2.5%] Asian, 3 [7.5%] Mixed Race) Oversampling for strong symptoms of anxiety. Participants completed DIAMOND and MINI semi-structured interview modules (Lecrubier et al., 1997; Tolin et al., 2018) on DSM-5 diagnoses, as well as a dimensional measure of self-report of depression and anxiety (IDAS-II). (Watson et al., 2012).

Uncertainty learning was measured using an aversive learning task in which participants chose between options that differed by two types of uncertainty: noise probabilities and change point. Participants' choices were first fitted to an established uncertainty learning model (Nassar et al., 2010, 2016), which assumes that participants learn about uncertainty at near-optimal levels. This model estimates values ​​for different sources of uncertainty (noise and changepoint probability) for each option on each trial assuming normative learning. A new version of this model was then developed, taking into account individual differences in any type of uncertainty learning. Participants' choices were also fitted to this individual difference model to estimate test-level uncertainty values ​​that represent individual differences in learning uncertainty.

Relationships between trial-by-trial noise and probability estimates of uncertainty change (from normative models and from individual differences) and behavior change for relationships with anxiety and stress were evaluated using test-by-test models.

Results:Participants had a range of psychiatric symptoms: the majority (30/40) met the criteria for anxiety disorder, trauma disorder, obsessive-compulsive disorder, and/or mood disorder, and of these, the majority (25/30) met the criteria. criteria for multiple disorders.

In the normative model, the noise measured from trial to trial decreased and the switch point probability increased the switching probability (noise main effect: z = -7.39, p < 0.001; switch point probability: z = 5 .02, p < 0.001). A factor measuring specific anxiety symptoms in the IDAS-II, but no factor measuring distress symptoms, was associated with a reduced effect of noise on behavior change (anxiety*noise interaction: z=3.08, p=0.002; Distress*noise: z = -1.052, p = .29).

The model, taking into account individual learning differences, showed excellent parameter recovery (correlation between simulated and retrieved parameters: rs 0.89 to 0.99; correlation between retrieved parameters: all rs < 0.35), suggesting that the model can independently measure different changes induced by uncertainty to learn with little error. Relationships between test-to-test true noise measures and probability of change compared to individual difference model estimates had negative interactions with anxiety symptoms (true noise * estimated noise anxiety: t = -2.38, p = 0.017, actual changepoint probability *Anxiety on estimated probability of change: t = -3.58, p <0.001), suggesting a weaker relationship between true and learned uncertainty measures with greater anxiety.

Conclusions:We successfully measured learning different types of insecurity in participants with a variety of anxiety and stress symptoms. Anxiety symptoms were associated with reduced behavioral effects of noise, assessed using a normative model. Using a model that could account for individual learning differences, participants' estimated uncertainty values ​​(both noise and probability of change) deviated more from true values ​​with increasing anxiety symptoms. Some of these relationships were specific to anxiety rather than stress symptoms. These results support difficulties in learning uncertainty in anxiety; in particular, that differences in learning about uncertainty cause perceptions of uncertainty to deviate from true values ​​in ways that affect anxiety-related decisions.

Key words:Anxiety, aversive learning, computational modeling, insecurity

To disclose:Aya Technologies: Consultant (own)

Nicole Moughrabi, Ameera Azar, Kevin Crombie, Joseph Dunsmoor, Zachary Stowe, Joshua Cisler*

University of Texas at Austin, Austin, Texas, USA

Background:Many real-world situations require navigational decisions for both reward and threat. While there have been significant advances in understanding the decision-making and mediation mechanisms of separate neurocircuitry for reward and threat, understanding of situations in which reward and threat contingencies compete to generate conflict avoidance approach (AAC) is limited.

Methods:Here we use computer learning models, independent component analysis (ICA) and multivariate pattern analysis (MVPA) to understand decision making during a novel task that incorporates simultaneous reward and threat learning and manipulates the congruence between reward and threat probabilities . 30 adult participants recruited from the general public completed the task during fMRI.

Results:Computer modeling supported a modified reinforcement learning model, in which participants integrated reward and threat scores into a combined total score according to an individually variable policy parameter that was highly predictive of decisions to address the reward or avoid the threat. during studies in which the highest reward option was also the highest threat option (ie, approach-avoidance conflict). ICA analyzes revealed unique roles for the prominence, frontoparietal, medial prefrontal, and inferior frontal networks in differential coding of threat and reward prediction errors and value cues. The left frontoparietal network clearly encoded the degree of conflict between reward and threat scores at the time of choice. The MVPA showed that reward and threat delivery could be accurately decoded within front-end networks of prominence and low quality, respectively, and that decisions to avoid reward versus threat were predicted by the relative degree to which these reward versus threat representations were active at the time of selection.

Conclusions:These data shed light on the computational and neurocircuitry mechanisms that support decision-making in approach avoidance conflicts. Computer modeling suggested that participants integrate reward and threat according to a different individual preference for approaching reward versus avoiding threat. Reward, threat, and reward versus threat conflicts were coded separately into large single neural networks. The MVPA results suggest that navigating UK decisions involves generating mental representations for possible decision outcomes, and the relative activation of these representations may influence subsequent decision-making to address a reward or avoid a consequence threat.

Key words:Conflict-avoidance approach, computational modeling, independent component analysis, multivariate pattern analysis

To disclose:Nothing to disclose.

Anne Andrews*, Merel Dagher, Sara Erwin, Katie Perrotta, Olena Lukoyanova, Audrey Nashner, Weiye Dai, Julia Brock, Alexandre Bonnin

University of California - Los Angeles, Los Angeles, California, United States

Background:Mood and anxiety disorders are common during pregnancy and can have negative consequences for both mother and child. Selective serotonin reuptake inhibitors are the most widely used drugs to treat mood and anxiety disorders. Human and animal studies suggest that serotonin signaling plays an important role in the susceptibility and manifestation of stress-related mood disorders. Furthermore, the serotonin system is an early orchestrator of brain development.

Methods:In this study, timed pregnant mice were exposed to chronic and unpredictable stress during the second half of their pregnancies using mild and/or ethologically relevant stressors. Some of these mice were given the antidepressant citalopram in their drinking water at the same time. After birth, serotonin levels in the brain tissue of the offspring were examined at three time points relevant to postnatal development for the maturation of the serotonergic system. A subset of adult pups were tested in behavioral tests to assess the long-term effects of in utero exposure. Finally, adult male offspring underwent ventral hippocampal microdialysis to study long-term neurochemical changes.

Results:Babies of stressed mothers had higher tissue serotonin levels and forebrain protein concentrations on the seventh postnatal day compared to controls. Adult male offspring exhibited greater anxiety-like behavior and a stronger stress response than sex-matched controls. These effects were rescued in male mice whose mothers were concurrently exposed to citalopram. No changes in basal or stimulated levels of serotonin in the hippocampus were observed in adulthood. However, adult males exposed to intrauterine stress experienced increased kappa opioid receptor agonist-induced serotonin release in the presence of serotonin transporter inhibition, which was attenuated by intrauterine exposure to citalopram.

Conclusions:These results suggest intergenerational benefits of treating maternal depression or anxiety during pregnancy, particularly in instilling stress resilience in adult male offspring.

Key words:Maternal stress, prenatal exposure to antidepressants, ventral hippocampus, intergenerational transmission of stress, stress resistance and vulnerability

To disclose:Nothing to disclose.

Rany Abend*, Julia Linke, Jordan Galbraith, Grace Ringlein, Laura Jett, Song Qi, Anita Harrewijn, Andre Zugman, Anderson Winkler, Daniel Pine

Universidade Reichman, Herzliya, Israel

Background:Anxiety disorders usually appear in childhood and adolescence, are pervasive and debilitating, and predict negative outcomes. Therefore, early intervention is of great clinical importance. Although anxiety disorders consistently manifest as excessive fear responses in anticipation of a threat, a lack of understanding of pathophysiological mechanisms hampers the development of treatments for affected adolescents. The limited mechanistic insights stem primarily from the challenges of experimentally eliciting fear in children and the distributed nature of the brain networks that support fear responses. Natural anxiety-provoking paradigms during functional imaging may provide an ecological route to study anxiety mechanisms that is particularly appropriate for children with anxiety. Graph theory is a computational approach that generates metrics that can quantify distributed functional interactions in the brain during naturalistic paradigms. Combining naturalistic fear induction with graphical theoretical approaches may provide a new method to identify the pathophysiological mechanisms underlying excessive anxiety in children with anxiety disorders.

Methods:Thirty adolescents with anxiety disorders (AD; seeking treatment, no drugs) and 34 healthy controls (HC) (9 to 17 years old, 38 females) completed two functional neuroimaging (fMRI) scans: resting state scan (baseline) and one with a "scary" (fear-inducing) animated movie. We recorded cognitive (nervousness scores) and physiological (skin conductance) fear responses and used a graph theory approach based on functional connectivity to identify links between brain network reconfiguration and pathological fear.

Results:Increased nervousness in anticipation of the movie, t(60)=3.06, p=0.003, and subsequent decrease, t(60)=2.74, p=0.008, confirmation of fear induction. AD reported greater nervousness than HC before the movie, t(62)=4.19, p<0.001, and showed greater physiological responses during the movie, t(57)=2.25, p=0.029, indicating well- followed by fear responses. Image analyzes showed changes in brain network configuration from baseline to film, p = 0.001. Importantly, a decrease in global connectivity between networks was observed during the movie in HC, V = 122, p = 0.02, but absent in AD. This effect was also manifested dimensionally with the severity of anxiety symptoms, r(62)=-0.39, p=0.002. Follow-up analyzes revealed a reconfigured control salience default mode network more strongly associated with attentional, visual, and reward networks in AD compared to HC, all pFDR < 0.05.

Conclusions:The film successfully and forcefully induced excessive physiological and cognitive anxiety responses in adolescents with anxiety disorders. State-induced anxiety was associated with an aberrant reconfiguration of distributed circuitry associated with pathological anxiety, suggesting a putative pathophysiological mechanism. This encourages further exploration of pathological mechanisms using naturalistic paradigms and a network perspective that captures aberrant patterns of distributed brain function.

Key words:Anxiety, functional magnetic resonance imaging (fMRI), developmental psychopathology, graph-based analysis

To disclose:Nothing to disclose.

Antonia Seligowski*, Hadil Zureigat, Simran Grewal, Shady Abohashem, Michael Osborne, Ahmed Tawakol

McLean Hospital, Harvard Medical School, Belmont, Massachusetts, EUA.

Background:Post-traumatic stress disorder (PTSD) has been repeatedly observed to be associated with an increased risk of major cardiovascular events (MACE, e.g., myocardial infarction, stroke, heart failure) and risk factors for MACE (e.g., example, increased blood pressure). However, there is controversy as to whether this association survives adjustment for potential confounders, including socioeconomic and lifestyle factors. A task force led by the National Institutes of Health identified numerous gaps in this literature and emphasized the need to further evaluate the PTSD-MACE linkage in large biobanks and characterize gender differences. Consequently, the current study used a large health biobank to determine whether a PTSD diagnosis was associated with an increased risk of MACE while controlling for important covariates. In addition, we examined possible gender differences in this association.

Methods:Participants included N = 118,995 adults who agreed to participate in the Mass General Brigham Biobank. A subgroup of N = 49,795 completed a health behavior questionnaire. PTSD and MACE diagnoses and covariates were determined by the presence of the corresponding ICD-10 codes. All analyzes were performed using SPSS version 24 with a significance level of p < 0.05. Covariates included socioeconomic factors (education, employment, income), lifestyle (exercise, smoking, obesity, alcohol use), and risk factors for cardiovascular disease (hypertension, hyperlipidemia, diabetes).

Results:PTSD diagnosis was significantly associated with MACE (odds ratio [95% confidence interval] = 2.04 [1.91, 2.18], p < 001, N = 102,395) after adjustment for cardiovascular risk factors. This effect remained significant after inclusion of socioeconomic factors (1.90 [1.68, 2.13], p<0.001, N=50,881) and lifestyle factors (1.81 [1.60, 2.04 ], p<<.001, N = 49.795). 🇧🇷 A univariate ANOVA was used to test the main effects of PTSD and gender on MACE while controlling for cardiovascular risk factors. A significant main effect was observed for PTSD (F[1,102,477] = 23.74, p<0.001), such that the risk of MACE was greater in patients with PTSD than without PTSD. A significant main effect was also observed for gender, such that the risk of MACE was higher in men than in women (F[1,102,477] = 37.32, p<0.001). PTSD by gender interaction was not significant.

Conclusions:Our results, from a large health biobank, expand on those of previous studies, showing that PTSD is a significant risk factor for MACE after controlling for important confounders, including risk factors for cardiovascular disease, lifestyle factors , life and socioeconomic factors. We also show that the risk of MACE is higher in men with PTSD, consistent with previous studies showing that premenopausal women have a lower risk of MACE than men (probably due to higher estradiol levels). Mechanistic studies are critical in determining the pathways by which men develop a risk for MACE relative to women with PTSD and how sex hormones affect these pathways.

Key words:PTSD, cardiovascular disease, sex and gender

To disclose:Nothing to disclose.

Matthew Girgenti*, Mario Skarica, Jing Zhang, Jiawei Wang, Hongyu Li, Dianne Cruz, Douglas Williamson, Hongyu Zhao, John Krystal

Yale School of Medicine, New Haven, Connecticut, USA

Background:Post-traumatic stress disorder is a multigenic disorder that occurs after exposure to severe trauma. Recent studies have begun to detail the molecular biology of the postmortem PTSD brain using tissue mass transcriptomic and epigenetic analyses. However, given the variety of molecular signaling pathways disrupted by PTSD identified to date (eg, glucocorticoid signaling, GABAergic transmission, and inflammatory signaling), it is unlikely that a single cell type is responsible. Therefore, there is a need to discover the contributions of each cell type to the molecular pathology of PTSD.

Methods:We isolated approximately 1 million postmortem human dorsolateral prefrontal cortex nuclei (BA 9/46) from cases and controls for single nuclear RNA sequencing in three diagnostic cohorts: PTSD, MDD (psychiatric control) and neurotypical controls for identify cells. neural and not identify . -type clusters and changes in gene expression specific to cell type. We then performed paired sequencing of the same samples for ATAC sequencing to measure differential chromatin accessibility. We identified open genomic regions harboring PTSD risk alleles and, by integrating snRNA and snATAC, identified disease-specific cis-regulatory elements. We use the latest and greatest GWAS for PTSD and MDD from the Million Veteran Program to identify cell types enriched for risky variants. We performed spatial transcriptomics on a subset of our cohorts to identify the specific cortical lamina where PTSD gene expression changes aggregate. Finally, we confirmed our results using a combination of low molecular weight in situ fluorescence (FISH) and digital quantitative PCR.

Results:We identified 67 distinct groups of cell types, including neuronal and non-neuronal cell types. We identified over 800 significantly differentially expressed FDR genes in many cell types and confirmed the expression changes of several genes implicated in the pathophysiology of PTSD using FISH and digital PCR. We found PTSD-specific cis-regulatory elements for several genes, including ELFN1, FKBP5, and SGK1. Integration of GWAS big data with our snATAC dataset revealed variant enrichment for PTSD, MDD, and other quantitative clinical phenotypes in excitatory and inhibitory neurons, and genome-wide spatial transcriptomics confirmed changes of layered, GABAergic signaling transcripts specific to DLPFC.

Conclusions:Taken together, this work is the first step towards creating a cell-type-specific atlas of stress disorders. Applying functional genomic approaches to characterize risk alleles within specific cell types will help determine which processes are most affected by stress. These results provide a comprehensive picture of the cell-type-specific molecular regulatory mechanisms that control the effects of stress in the human cerebral cortex and provide a model for integrating genomic data from individual cell types to characterize the molecular landscape of other brain regions. . traumatic stress.

Key words:PTBS, MDD, Genomik, single cell omics

To disclose:Nothing to disclose.

Vena Martinez*, Jiawei Wang, Hongyu Li, Dianne Cruz, Douglas Williamson, Hongyu Zhao, Ronald Duman, John Krystal, Matthew Girgenti

Yale University, New Haven, Connecticut, USA. UU.

Background:The brain's gene regulatory landscape is highly dynamic in health and disease, coordinating many biological processes in different cell types. Complex psychiatric disorders such as PTSD result from differences in different levels of regulation (epigenomics, transcriptomics and proteomics) and converge on specific biological signaling pathways of clinical importance. We are beginning to understand more about the neurobiology of PTSD and the molecular mechanisms involved, but many critical questions remain.

Methods:Here, we generate a large multi-omics set of postmortem brain data from PTSD donors compared to neurotypical controls and a psychiatric (major depressive) control group, spanning RNA expression, DNA methylation, and brain protein expression. dorsolateral prefrontal cortex, amygdala, and hippocampus Single-core RNA-seq data were generated to infer cell-type-specific expression.

Results:Integration of signaling pathways identified by multiliomics, including glucocorticoid signaling, GABAergic transmission, and inflammation, which are differentially enriched in PTSD and MDD. At the RNA and methylation level, there was differential expression aggregation at specific PTSD risk loci, including CRHR1, ELFN1, and MAD1L1.

Conclusions:This approach highlights the unique genomic properties of both diseases and shows how convergent pathways between molecular modalities contribute to the stress-associated etiology.

Key words:TEPT, GWAS, ATAC-seq, RNAseq

To disclose:Nothing to disclose.

Katharina Domschke*, Miriam Schiele, Jan Lipovsek, André Pittig, Benjamin Straube, Jan Richter, Ulrike Lüken, Andreas Ströhle, Elisabeth Binder, Tilo Kircher, Alfons Hamm, Volker Arolt, Hans-Ulrich Wittchen, Angelika Erhardt, Anna Köttgen, Jürgen Deckert

University of Freiburg, Freiburg, Germany

Background:Within the vulnerability-stress pathogenetic model of mental disorders, epigenetic mechanisms such as DNA methylation have been proposed to play a dynamic role at the interface between the genetic and environmental levels. Here, genome-wide DNA methylation patterns were examined as disease markers of anxiety disorders and as potential predictors and/or mechanisms of response to psychotherapy.

Methods:A longitudinal association study across the epigenome (Illumina MethylationEPIC BeadChip) was performed at baseline (BL), post-treatment (POST) and at 6-month follow-up (FU) in the largest sample of patients with anxiety disorders up to the time. date (N = 415, f = 238; mean age ± SD: 33.29 ± 11.3 years; panic disorder with or without agoraphobia: N = 257; social anxiety disorder: N = 129; multiple specific phobias: N = 29) who were treated with cognitive behavioral therapy (CBT) based on standardized exposure and in 317 healthy controls.

Results:A significant association across the epigenome was found for altered DNA methylation at 256 CpG in the panic disorder subsample compared to healthy controls. In the general sample of patients with anxiety disorders, evidence of altered DNA methylation at ten and two CpG sites, respectively, was found to predict response to treatment in POST and FU. Evidence of DNA methylation changes throughout the epigenome, along with a CBT response in anxiety disorders, was seen in 13 CpGs from BL to POST and in nine CpGs from BL to FU. Several hits are attributed to genes previously involved in processes related to anxiety, learning or plasticity.

Conclusions:The identification of epigenetic biomarkers of anxiety disorders can help to develop preventive measures that improve resilience. Defining epigenetic signatures as predictors or core mechanisms of action of exposure-based interventions should contribute to the development of more specific personalized treatments for anxiety disorders.

Key words:EWAS, epigenetic biomarkers, DNA methylation, psychotherapy, precision medicine for mood and anxiety disorders

To disclose:Janssen Inc.: Advisory Board (own)

Amanda Morgan*, Veronika Kondev, Sachin Patel

Northwestern University, Chicago, Illinois, USA. UU.

Background:Life-threatening traumatic experiences can have lasting negative consequences, many of which involve the development of maladaptive pathologies. There is a complex relationship between traumatic stress events and chronic neuropsychiatric conditions, including PTSD, anxiety and depression. A translational model of life-threatening trauma in rodents uses exposure to a predatory odor (2MT) to elicit fear behaviors in mice. In both rodents and humans, the neural substrates underlying traumatic experiences are diverse, and the basolateral amygdala (BLA) is heavily involved in processing trauma and stress.

Methods:We examined BLA neuronal activity in vivo during olfactory exposure to predators by measuring calcium transients with fiber photometry in male and female mice.

Results:Previously, we showed that 2MT increases amygdala endocannabinoid (2-AG) levels and here we report a systemic pharmacological manipulation of endocannabinoids that modulates BLA activity during exposure to predator scent.

Conclusions:Different trauma response modes directly correlate with different patterns of activity in the BLA, and these effects are mediated by the endocannabinoid system.

Key words:Amygdala, acute traumatic stress, endocannabinoids

To disclose:Nothing to disclose.

Emily Wright*, Rochelin Dalangin, Sally Ho, Lin Tian

University of California, Davis, Davis, California, USA

Background:We have developed a new serotonin biosensor, iSeroSnFR2.0, which has improved sensitivity and a lower dissociation constant (Kd) compared to the iSeroSnFR1.0, providing greater ability to measure serotonin concentrations in subseconds in several studies using fiber photometry . Here we use this powerful tool to record the dynamics of serotonin release during two anxiety-provoking states. We recorded the bed nucleus of the stria terminalis (BNST) and the orbitofrontal cortex (OFC) during fear learning, as these regions are innervated by distinct populations of serotonergic neurons in the dorsal raphe.

We also examined the effects of chronic social defeat on serotonergic transients. By measuring serotonin release under conditions of chronic and acute stress, we intend to obtain a more complete picture of how exposure to adverse stimuli modulates serotonin release.

Methods:Experiment 1: All recordings were made by fiber photometry using iSeroSnFR1.0 or iSeroSnFR2.0 expressed in BNSTs or OFCs from adult male mice. Mice were then subjected to a 3-day fear conditioning paradigm. On the first day of testing, mice received 5-tone tests followed by 10-tone/shock tests. On the second test day, mice were tested with 15 tones/shock. On the third day of testing, mice received 5 tone/shock challenges, followed by 10 tone challenges. n = 7-9 per group.

Experiment 2: All recordings were made by fiber photometry using iSeroSnFR2.0 expressed in BNST from adult male mice. Mice were subjected to chronic social defeat (or control treatment) for 10 consecutive days with 10 different CD1 stressor mice. 24 hours after the last day of defeat, the mice were submitted to a social interaction test in a cage. During this test, mice spent 3 minutes in an empty neutral arena, 3 minutes with an empty wire cage placed in the arena, and 3 minutes with a new incarcerated CD1 offender placed in the arena. Two days later, the mice were tested again, this time in a cageless social interaction test. During this test, mice spent 3 minutes in an empty neutral arena, 3 minutes with a new male of the same strain, and 3 minutes with a new male CD1 stressor. Control n = 2, stressed n = 5.

Statistical analysis: Raw photometry data were reduced 100 times. The isosbestic channel was then fitted to a biexponential curve and this curve was subtracted from the signal to correct for fading. ΔF/F% was calculated as [100∗(signal 465 - adjusted signal)/adjusted signal)] and these results were then z-weighted. Data were then averaged across experiments and animals. Area under the curve (AUC) analyzes were performed from the beginning of the tone to just before the onset of the shock. AUC was calculated as the sum of the area under the middle trace and above y = 0. Parametric t-tests were used to determine significant differences between AUC values.

I also add preliminary data from machine learning tracking of mice during caged and cageless social interaction tests with Deeplabcut. The use of position estimation data to track animal behavior and correlate it with photometry data is ongoing.

Results:Experiment 1: AUC analysis shows significantly less response to tone-only studies in pre-shock studies than studies consisting of tone + shock or post-shock study alone. discharge for both iSeroSnFR1.0 BNST (p < 0.01), iSeroSnFR1.0 OFC (p < 0.01), iSeroSnFR2.0 BNST (p < 0.01) and iSeroSnFR2.0 OFC (p < 0.01) . In the initial tone/shock experiments on day 1, we found that serotonin in the BNST/OFC is released after the mouse receives the paw shock, but as the experiments progress, serotonin input is triggered by the onset of the tone. This pattern is most evident in mice injected with iSeroSNFR2.0.

Experiment 2: For social interaction in the cage: All test mice did not show a significant response to time spent in the empty arena or being placed in an empty cage. All test mice increased serotonin release from the BNST in response to placing the caged CD1 offender in the arena, with no significant differences between groups. For out-of-cage social interactions: There was no statistically significant difference in response to time spent in the empty arena or to initiating an out-of-cage interaction with a new C57 male. Stressed males showed increased serotonin in the BNST at the start of an out-of-cage interaction with a novel male CD1 stressor, which is not seen in non-stressed males (AUC p < 0.05).

Conclusions:Although the firing patterns of serotonergic neurons have been described, other neuroimaging techniques have not made it possible to measure serotonin release from spatially displaced extremities with a high degree of temporal specificity. Here, my work demonstrates that the iSeroSnFR2.0 can track experiment-specific changes in endogenous serotonin release within a fraction of a second. These results indicate that the increased sensitivity at lower serotonin levels achieved by iSeroSNFR2.0 allows a more complete and accurate picture of serotonin release dynamics to be captured than is possible with iSeroSNFR1.0.

Results from fear conditioning and chronic social stress show that the split-second release of serotonin transiently and rapidly tracks anxiety and anticipates punishment. Declaring serotonin can play a crucial role in preventing risky behavior or encouraging a quick way out of an unfavorable situation. Future directions include acute versus chronic administration of SSRIs prior to anxiety conditioning or chronic social stress.

Key words:Serotonin, fiber photometry, optical biosensors, acute and chronic stress

To disclose:Nothing to disclose.

Mashal Ahmed, Christina F. Pereira, Laura M. Best, Rachel F. Tyndale, Dafna Rubin-Kahana, Bernard Le Foll, Isabelle Boileau, Stefan Kloiber*

Centre for Addiction and Mental Health, University of Toronto, Toronto, Canadá

Background:Social anxiety disorder (SAD) is one of the most common psychiatric disorders worldwide. Despite ongoing clinical efforts, response rates to conventional pharmacotherapies remain low, requiring exploration of new neurobiological mechanisms. Preclinical evidence suggests that defective signaling of the major endocannabinoid neurotransmitter anandamide, via the upregulated activity of its catabolic enzyme, fatty acid amide hydrolase (FAAH), may be involved in the pathophysiology of anxiety spectrum disorders. However, there are no in vivo clinical studies examining the status of brain FAAH in people with SAD. The aim of this study was to determine, using positron emission tomography (PET) imaging with the new radioligand FAAH [11C]CURB, whether brain levels of FAAH in subjects with SAD compared to healthy controls (HC) are increased .

Methods:Sixteen participants who met the DSM-5 diagnostic criteria for SAD underwent PET imaging with arterial blood samples. [11C]CURB λk3, an index of FAAH levels in the brain, was examined in the brain and 9 regions of interest (ROI) using ANCOVA repeated measures to control for genetic variability known to drive the linkage of affected [ 11C]CURB (FAAH rs324420 C>A). The severity of SAD symptoms was assessed using the Liebowitz Social Anxiety Scale (LSAS).

Results:People with SAD (n = 16; F/M = 13/3; 26.88 ± 5.78 years; FAAH rs324420: 11 CC, 4 AC, 1 AA) had 8.78% greater whole-brain [11C] CURB λk3 (F(1.59)=5.190, p=0.026) compared to HC (n=46; F/M=24/22; 27.17±8.47 years; FAAH rs324420: 32 CC , 12 BC , 2AA). Significant interaction was also observed between group [2] and ROIs [9] (F(5,023,296.36)=2.52; p=0.029). Paired comparisons of post-hoc LSD revealed that [11C]CURB λk3 was significantly increased in 3 of 9 ROIs (p<0.05) (hippocampus, ventral striatum, dorsal striatum). A partial correlation control for the FAAH genotype revealed that whole brain [11C]CURB λk3 did not correlate with the total LSAS score or any LSAS subscores.

Conclusions:Consistent with our hypothesis and preclinical evidence, our preliminary results suggest that whole-brain FAAH levels are significantly elevated in subjects with SAD compared to CH, as inferred from [11C]CURB binding. The mechanism behind FAAH enzymatic activity in SAD is unknown. However, initial results from this pilot study support up-regulated FAAH activity as a potential neurobiological mechanism in SAD and may inform future development and research of interventions targeting FAAH.

Key words:Social anxiety disorder, endocannabinoid system, PET imaging, FAAH

To disclose:Empowerpharm: Advisor (automatic)

Meredith Reid*, Sarah Whiteman, Thomas Denney, Abigail Camden, Stephanie Jeffirs, Frank Weathers

Auburn University, Auburn, Alabama, USA. UU.

Background:People with PTSD often report difficulties with working memory, but the neural basis for their dysfunction is not well understood. Previous fMRI studies of PTSD have shown reduced activation in the dorsolateral prefrontal cortex (DLPFC), a critical brain region for working memory. Consistent evidence from animal models and human studies point to glutamatergic dysfunction in key brain regions in PTSD. It is possible that glutamatergic abnormalities could be behind the different activation patterns observed in DLPFC; However, this has not been directly tested. Functional magnetic resonance spectroscopy (fMRS) can potentially solve this problem by measuring glutamate changes associated with neuronal activity in response to stimuli. Furthermore, MRS studies on DLPFC in PTSD are lacking. Therefore, in this study, we used 7T-MRS in the resting state as well as fMRS during the N-back working memory task to measure glutamatergic changes in DLPFCs from people with PTSD, trauma-exposed people without PTSD, and people without trauma. We hypothesized that (1) glutamate would be reduced in people with PTSD, (2) glutamate would be increased by working memory stress, and (3) the relationship between glutamate and working memory would be altered in PTSD.

Methods:Participants completed the Life Events Checklist (LEC-5 Extended Version) and the PTSD Checklist for DSM-5 (PCL-5). This study included 26 people with PTSD (age: 28.2 +/- 8.3; gender: 20 F / 6 M), 21 trauma-exposed people without PTSD (TE; age: 29.6 +/- 9.0 ; sex: 10 F / 11 M ) and 24 people without trauma (NT; age: 29.6 +/- 11.2; gender: 15 F / 9 M). Images were performed at the Auburn University MRI Research Center on a Siemens MAGNETOM 7T MRI scanner equipped with a 32-channel head coil. Structural images were obtained for voxel placement. Spectra were acquired from the left DLPFC (25 x 25 x 25 mm) using an ultrashort TE-STEAM sequence (TR/TE/TM = 10,000/5/45 ms), FASTESTMAP adjustment, and VAPOR water suppression. For the MRS resting state, 32 water-suppressed and 4 non-water-suppressed stockings were collected while participants were fixed to a cross. During fMRS, participants completed the N-back task. The stimuli were single letters presented one after the other. The task included 9 alternating blocks of 0-back, 1-back, and 2-back conditions (3 blocks of each working memory load). For fMRS, 8 water-suppressed media were collected during each block and the spectra were combined in MATLAB. The MRS and fMRS spectra were analyzed in LCModel using a simulated base set. The spectra were corrected for eddy currents and quantified using the unsuppressed water signal. MRS glutamate levels were compared between groups using one-way ANCOVA, controlling for age and sex. A linear mixed-effects model controlling for age and sex was used to examine the effects of group, condition, and group*condition interaction on fMRS glutamate levels.

Results:For resting MRS, we observed a significant group effect (F(2.65) = 5.20, p = 0.0008). Specifically, glutamate was significantly lower in PTSD vs NT (p(Tukey) = 0.023) and in TE vs NT (p(Tukey) = 0.019). For fMRS, the condition effect and the interaction between group and condition were not significant. However, we observed a significant group effect (p < 0.001). In particular, glutamate was lower across all conditions in PTSD vs. NT (t = 3.79, p < 0.001) and in TE vs. NT (t = 2.95, p = 0.005). Percent change in glutamate was calculated relative to passive MRS fixation and was greater for NT (5.0-5.9%) compared to PTSD (2.5-2.7%) and TE (1.5 -2 ,two%).

Conclusions:We observed (1) less glutamate in trauma-exposed people with and without PTSD compared to people without trauma, and (2) increased glutamate during the task compared to passive gaze. Our findings are consistent with previous studies reporting lower levels of glutamate in the anterior cingulate cortex of people with PTSD and add to the growing evidence of glutamatergic abnormalities associated with traumatic stress. In future work, we will investigate the link between glutamate and brain activation using fMRI. As fMRS and fMRI study different aspects of neuronal firing and synaptic activity, the combined approach of these techniques could better characterize the neurobiological basis of working memory deficits in PTSD.

Key words:PTSD, functional magnetic resonance spectroscopy, glutamate, working memory

To disclose:Nothing to disclose.

Shan Siddiqi*, Noah Philip, Stephan Palm, Heather Bouchard, Jennifer Barredo, Jordan Grafman, Rajendra Morey, Michael Fox

Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, EUA. UU.

Background:The optimal purpose of transcranial magnetic stimulation (TMS) for post-traumatic stress disorder (PTSD) is still unknown, and clinical trials have produced mixed results. The connectivity of symptom-causing lesions has been shown to predict the effectiveness of neuromodulation targets for the same symptoms, including depression, motor parkinsonism, cognitive symptoms of Parkinson's disease, and tics. The risk of PTSD has been shown to be reduced after tonsil injuries, but the tonsil is too deep to be directly accessible with TMS. Therefore, we used brain injuries to map a circuit-based TMS target for PTSD in veterans. We analyzed three datasets to derive a specific circuit-based TMS target for PTSD in military veterans.

Methods:First, we tested whether the risk of PTSD is reduced after damage to specific brain regions (using voxel injury symptom mapping) or specific brain circuits (using injury network mapping) in veterans who suffered penetrating trauma (n = 193). We used halved cross-validation to confirm significance. Second, we tested whether our brain-injury-derived “PTSD circuitry” was abnormal in brain-injured veterans (n ​​= 180) using resting-state functional connectivity (rsFC). Finally, we tested whether connectivity changes in this circuit were associated with an improvement in PTSD symptoms after TMS (n = 10 active, 10 sham). We controlled for depression and tested circuit specificity in all analyses.

Results:The sites of injury that reduce PTSD risk are mapped to common brain circuitry that includes the medial prefrontal cortex (mPFC), amygdala, and anterior temporal lobe. Lesion network maps derived from half of the patients predicted PTSD status in the other half (p = 0.01). This result persisted even when all lesions overlapping the tonsil were excluded (p < 0.05), demonstrating that this is a circuit-level phenomenon. Connectivity within this circuit, but not in other circuits, was associated with the diagnosis of PTSD in patients without brain injury (p < 0.01) and improvement in PTSD after TMS (p < 0.05).

Conclusions:The sites of lesions that protect against PTSD are mapped to common brain circuitry. This circuit is abnormal in patients with PTSD without brain injury, is associated with a TMS-induced improvement in PTSD severity, and may serve as a target of neuromodulation for veterans with PTSD symptoms.

Key words:PTSD, TMS, circuit-based approach, Läsion

To disclose:Magnus Medical: Advisor (Own), Brainsway Inc: Stocks/Stocks (Own)

Alice Hill, Huzefa Khalil, Klaudia Laborc, Savannah Kounelis-Wuillaume, Colin Johnston, Isaac Agranoff, Swapnil Gavade, Benjamin Singer, Huda Akil, Joanna Spencer-Segal*

University of Michigan, Ann Arbor, Michigan, USA. UU.

Background:Neuropsychiatric symptoms affect half of survivors of serious illness, creating a significant public health burden. Glucocorticoids are often given to patients with acute illnesses for their cardiovascular and anti-inflammatory properties, but they also affect brain outcomes. Interestingly, randomized and observational clinical trials show that glucocorticoid treatment during critical illness reduces the risk of post-traumatic stress disorder (PTSD) in survivors, but the mechanisms are unknown. We hypothesize that treatment with glucocorticoids during illness may affect hippocampus-dependent cognitive and/or emotional processes in survivors.

Methods:We used cecal ligation and puncture (CLP) to induce systemic infection in male and female mice (N = 80, evenly distributed between groups) and treated them with corticosterone (week 16) during acute illness (days 1-5). mg/kg) or vehicle. 🇧🇷 Disease severity was measured by locomotion and daily weight. From day 14, we looked at affective behavior and neuroendocrine function. The open field and elevated plus maze were used to measure negative affect, while the object recognition test was used to measure memory. Basal and stress-induced (forced swimming) ACTH and corticosterone were measured from plasma using an ELISA, and systemic inflammation was measured using spleen cell counts by flow cytometry. The dorsal and ventral hippocampus were dissected from half of the mice and the RNA isolated and prepared for 50 bp end-paired RNA sequencing performed on an Illumina NovaSeq S4.

Results:Corticosterone prevented CLP-induced weight loss without significantly affecting disease-induced exercise behavior or overall survival. After a 14-day recovery, surviving male and female CLP mice exhibited persistent adverse effects based on decreased open area exploration in open field and elevated plus maze, and this did not resolve with corticosterone treatment. On the other hand, corticosterone treatment during illness affected survivors' performance on the object recognition test. Mice that survived CLP showed evidence of increased central hypothalamic-pituitary-adrenal (HPA) axis activity based on elevated baseline ACTH levels, but corticosterone treatment during illness had no effect on HPA axis function in survivors. There was also evidence of ongoing systemic inflammation in CLP survivors based on spleen cell counts that did not recover with corticosterone treatment.

RNA sequencing revealed different neuronal signatures of CLP and corticosterone treatment. 103 genes were differentially expressed in CLP survivors and 2076 genes were differentially expressed after corticosterone treatment, with only 6 genes overlapping. CLP survivors showed sustained upregulation of genes related to inflammation and immunity that were not altered by corticosterone treatment. Correlation of elevated plus maze behavior with gene expression revealed a panel of 126 genes in the ventral hippocampus that are associated with affective behavior after CLP, most of which are involved in neuroendocrine signaling rather than inflammatory or immunological processes.

Conclusions:In conclusion, murine survivors of CLP-induced acute infectious disease showed persistent adverse effects and increased activation of the central HPA axis. Although persistent systemic and neuronal inflammation has been observed in CLP survivors, correlation of gene expression with behaviorally altered neuroendocrine signaling affected the ventral hippocampus and not neuroinflammation in CLP survivors. Corticosterone treatment during illness did not rescue negative affect in survivors, but it did impair object memory and altered the expression of 10% of detectable transcripts in the dorsal and ventral hippocampus. These results provide the first insight into mechanisms related to affective and cognitive decline after acute illness. The data suggest that neuroendocrine signaling in the ventral hippocampus is important for emotional outcomes, highlighting the role of glucocorticoids in cognitive outcomes. Future work will address the resulting hypothesis that glucocorticoids may alter PTSD risk by altering hippocampus-dependent memory processes.

Key words:Glucocorticoid, Hippocampus, Infection

To disclose:Camurus AB: Contract Research (own expense), Recordati Rare Diseases: Advisory Board (own expense), Chiasma Inc.: Advisory Board (own expense)

Sija van der Wal, Elbert Geuze*, Livia Dominicus, Edwin van Dellen, Remko van Lutterveld, Eric Vermetten

Ministry of Defence, Netherlands, Utrecht, Netherlands

Background:Active duty military personnel are frequently exposed to traumatic events during deployment, but only a minority of them develop mental disorders such as post-traumatic stress disorder (PTSD). It is not fully understood why some are at greater risk of developing PTSD after implantation. A large body of literature has been published to identify risk factors for PTSD, but this has not yet led to the development of effective pre-use screening tools. Machine learning can be a promising approach to develop better predictive models.

Methods:The present study used a randomized forest method to predict the development of PTSD symptoms up to ten years after deployment in the PRISMO cohort of Dutch Afghan veterans (N = 963). The dataset consisted of psychological and biological variables before implantation.

Results:The predictive model performed well above chance (AUC = 0.71, sensitivity = 0.63, specificity = 0.69). The five highest ranking predictive characteristics included self-reported symptoms (depression, anxiety and suspiciousness, and personal sensitivity) and laboratory markers (vasopressin sensitivity and DEX). A random forest model that uses a dataset that uses only psychological predictors and the random forest model based on psychological and biological information.

Conclusions:The results suggest that a randomized forest approach can be effective in identifying key predictive markers to define new risk reduction interventions. As the performance of the model in the present study was modest and external validation could not be performed, more research is needed to improve usability for pre-implementation testing.

Key words:PTSD, machine learning, PTSD, prediction, causal modeling, trajectory modeling, cortisol

To disclose:Nothing to disclose.

Samantha Friend*, Sorana Caldwell, Rahul Nachnani, H. Kirk Hammond, Victoria Risbrough

VA San Diego Healthcare System, San Diego, California, USA

Background:Growing evidence suggests that inflammation plays a role in psychiatric disorders caused by trauma. Studies suggest that post-traumatic stress disorder (PTSD) is associated with abnormalities in serum C-reactive protein (CRP) and mutations in the CRP gene. We examined the potential causal role of CRP in mouse models of PTSD and hypothesized that CRP expression may confer increased risk of PTSD-like behavior.

Methods:Avoidance and conditioned fear processes were tested in male and female C57BL6J mice without PCR. Male wild-type C57BL6J mice were given an intrajugular injection of 10^11 copies of the AAV8.CRP or AAV8.Null genome and tested four weeks later in the predator stress model of PTSD, which assesses persistent avoidance behavior and specific fear of trauma responses 1-2 weeks after exposure to a big cat.

Results:Female mice without PCR have greater memory of extinction anxiety at baseline (FCRP = 1.794, n = 15, p = 0.0053). Despite an almost three-fold increase in protein levels (17.63 pg/ml for AAV8.CRP vs. 6.34 pg/ml for AAV8.null), male mice overexpressing AAV8.CRP did not have an increased risk of PTSD avoidance behaviors or changes in extinction anxiety in males after predatory stress.

Conclusions:Loss of CRP signaling supports an increase in extinction anxiety in females but not in males. Men also show no effects of CRP overexpression, suggesting that women are more susceptible to the effects of CRP on PTSD-related behaviors. Future studies will examine how constitutive CRP expression contributes to fear behavior after trauma and how CRP overexpression contributes to the effects of trauma in female mice. Studies are ongoing on how CRP alters peripheral and central immune responses after trauma.

Key words:C-reactive protein, fear conditioning and extinction, neuroimmunology, stress and anxiety behavior

To disclose:Nothing to disclose.

Paul Thomas, Beatriz Peñalver, Suzanne Alvernaz, Jun Ma, Olusola Ajilore*

University of Illinois at Chicago, Chicago, Illinois, USA. UU.

Background:The role of the gut-brain axis in the internalization of psychopathologies is increasingly recognized. The present study examined dynamic connectomes by formulating a joint analysis of brain/microbiome networks in participants with depression and obesity to understand coupled changes over time after the intervention.

Methods:Participants came from a study that examined the effectiveness of specialized behavioral therapy over 2 months. A subgroup (n = 26, 8: usual care, 18: intervention) with gut microbiome/neuroimaging data at baseline and after 2 months was included in our analyses. For each subject, an individual brain sample and microbiome network were derived at both time points and presented as tensors. Common tensor factorization was used to couple subject mode tensor decomposition to identify common variations in brain/microbiome networks, and subject factors derived from the analysis were used to relate clinical scales to network changes.

Results:A subject factor was significantly correlated with reductions in GAD-7 (rho = 0.547, p = 0.007, q = 0.045). The associated brain network factor consisted of negative connections between limbic/default mode network regions. For the microbiome network factor, the predominant connectivity came from the Bacteroidaceae/Lachnospiraceae families. Furthermore, we found that coupled factorization provided the best grouping of participants with 96% accuracy, followed by independent taxa (85%) and brain network factorizations (69%).

Conclusions:Coupled tensor decomposition can be used to identify common temporal changes in the brain/microbiome networks of participants receiving treatment for comorbid obesity and depression, suggesting that incorporating heterogeneous data fusion uniquely reveals prominent network features.

Key words:Gut microbiome, brain connectome, depression, obesity, anxiety

To disclose:KeyWise AI: Founder (auto), Embody Labs, Blueprint, Milken Institute, Sage Therapeutics: Advisory Board (auto),

Sanne van Rooij*, Sean Minton, Timothy Ely, Cecilia Hinojosa, Nathaniel Harnett, Abigail Powers, Tanja Jovanovic, Daniel Drane, Kelly Bijanki, Jon Willie

Emory University School of Medicine, Atlanta, Georgia, USA

Background:A better understanding of the neurobiology of post-traumatic stress disorder (PTSD) may reveal new targets for neuromodulation and improve treatment outcomes. One such target could be the amygdala, a key region in the threat neurocircuitry. A hyper-reactive right amygdala (R) combined with ventromedial inferior prefrontal cortex (vmPFC) control has been associated with PTSD. In addition, brain damage, including that of the amygdala, has been shown to protect against the development of PTSD; However, due to their invasive nature, neurosurgical procedures have not been studied for PTSD.

Methods:This unique case series reports prospective data from 10 epileptic patients who underwent unilateral ablation for treatment-refractory epilepsy. Data are presented as a case series, as the differential nature of the ablations does not allow analysis at the group level. Before and >6 months after surgery, PTSD symptoms were assessed using the Physician Administered PTSD Scale (CAPS) for DSM-5, and fMRI MRI scans were performed at both time points to assess threat reactivity and functional connectivity (for N = 5 ). Neuroimaging analyzes were performed in native space using Statistical Parametric Mapping 12 and CONN Toolbox. Post-ablation scans were co-registered with pre-ablation scans of the same modality to ensure that all scans were in the same natural region. The regions of interest (ROI) were L amygdala (probabilistic atlas CITI168) and vmPFC (WFU PickAtlas, BA25) and were constructed for the first time in the standard MNI space. The pre-ablation structural image was normalized to MNI space and inverted normalization parameters were used to convert ROIs to native space. Average ROIs were extracted using the REX toolbox. The mean difference in contrast value for anxious versus neutral faces was calculated as a measure of threat reactivity. The CONN toolbox was used to calculate amygdala-vmPFC functional connectivity (FC) during threat response.

Results:Five patients met before or after ablation for PTSD. Patients (Pt) 1 and 2 were no longer treated for PTSD after Ramygdala ablation. Pt 2 showed before and after treatment a decrease in left amygdala (L) threat reactivity (-0.27), an increase in vmPFC reactivity (+0.14) and an increase in vmPFC-tonsyl FC ( + 0.29). Patient 3 did not recover from PTSD after Ramygdala + R temporal pole ablation. He also developed suicidal thoughts after the operation. It showed minimal change in threat reactivity (-0.07 for L-amygdala and +0.04 for vmPFC) and a decrease in vmPFC-amygdala FC (-0.36). Patient 4 was exposed to trauma without PTSD but developed PTSD after Ramygdala + temporal pole ablation. Patient 5 underwent previous surgery, sparing his ramygdala. A car accident led to more seizures and the development of PTSD. She underwent an open tonsillar resection, after which her PTSD improved, but the seizures continued. Five patients with epilepsy without PTSD (MRI data for N = 3) undergoing L-tonsyl ablation were evaluated as controls.

Conclusions:This case series supports that the amygdala is crucial in the maintenance of PTSD symptoms, supports previous work on the role of the amygdala in PTSD treatment failure, and supports the amygdala as an important target of neuromodulation. The results also suggest that ablation of the temporal pole of R is associated with poor PTSD outcomes, following another case report finding findings of lower activation and size in PTSD, suggesting that the temporal pole is an important brain region for further study.

Key words:Tonsil ablation, post-traumatic stress disorder, epilepsy, temporal pole, threat response

To disclose:Nothing to disclose.

F. Andrew Kozel*, Megan Senda, Isabelle Taylor, Mariah Jensen, Kevin Johnson

Florida State University, Tallahassee, Florida, USA

Background:Dysphoria is a transdiagnostic symptom of discomfort or dissatisfaction that occurs in a variety of diagnoses, including mood and pain disorders. Dysphoria can share basic similarities in mechanisms, and therefore treatments that target dysphoria can have broad effects. Traditionally, studies have focused on specific inclusion criteria for narrow diagnoses, excluding concomitant diagnoses. In clinical practice, comorbidities with dysphoria are quite common (eg, depression and pain), so a transdiagnostic approach may better reflect the clinical reality. The aim of this project was to test a sequenced approach for the rapid treatment of dysphoria. In the first step ("Phase 1"), we wanted to determine the feasibility and effectiveness of Virtual Reality (VR) treatment sessions. In the following steps, as indicated, we attempted to determine the efficacy, tolerability, and feasibility of accelerated transcranial magnetic stimulation (accel-TMS) for dysphoria, starting with sessions of stimulation of the left dorsolateral prefrontal cortex ("Phase 2A"), followed sequentially by sessions stimulating the dorsomedial cortex ("phase 2B").

Methods:Participants were 18 years of age or older and were recruited from the community. Inclusion criteria for dysphoria were depression (PHQ-9 ≥ 10), anxiety (GAD-7 ≥ 10), PTSD (PCL-5 ≥ 45), or chronic pain (mean pain intensity ≥ 4/10 for > 3 months) . We defined response operationally as a 30% improvement on the primary symptoms scale, with efficacy assessed separately on clinically graded scales. Participants were excluded due to medical contraindications to TMS and other major psychiatric diagnoses. Phase 1 was a series of mindfulness exercises in virtual reality twice a day for 10 days. Those who did not respond to the virtual reality treatments moved on to phase 2A of the accel-TMS (five sessions per day at 50-minute intervals for 5 days, 25 sessions in total). Phase 2A included stimulation of the left dorsolateral prefrontal cortex (modified F3 bundle), 110% manual motor threshold, 1800 iTBS pulses. One week after treatment, responders continued for 5 more sessions over 5 weeks. Participants advanced to Phase 2B treatments if they did not respond to Phase 2A or remained symptomatic after Phase 2A, as defined by the inclusion criteria. Phase 2B was Accel-TMS (five sessions per day at 50-minute intervals for 5 days, a total of 25 sessions) plus 5 sessions over 5 weeks. Phase 2B included stimulation of the dorsomedial prefrontal cortex (midline, 25% nasion-inion distance, from nasion), 110% foot motor threshold, 1800 pulses of 10 Hz theta burst (600 iTBS pulses followed by 1200 pulses of 10 Hz).

Results:This interim report is based on 20 participants registered, with 1 screen failure, and 19 initiated for Phase 1. For Phase 1 (mindfulness in VR), 10 participants completed the full 10 days, 3 participants completed 5 days, and 6 participants they gave up. before 5 days. The reasons for discontinuing VR were no change in symptoms (n = 9), disgust with VR (n = 6), nausea (n = 1) and pain that prevented them from continuing to go to the laboratory for VR (n = 1 ). = 1). There were 5 participants who did not proceed to Phase 2A (1 responded with improvement in chronic pain and 4 participants chose not to proceed). There were 14 participants who moved on to Phase 2A (3 of the responders completed the study and 3 are waiting to complete Phase 2B). Eight participants advanced to Phase 2B, with two of the eight (25%) responding. All participants completed the full Acute Phase 2A and 2B regimens without major adverse events.

Conclusions:Most tolerated the VR treatments, but 37% (7/19) considered the experience negative. Of the 14 who progressed to accelerated TMS phase 2A, all completed the full week (25 sessions) and tolerated the treatment well. In both the accel-TMS phase 2A and subsequent accel-TMS phase 2B, there was a modest response (21%, 25%) despite only 1 week of treatment. Our enrolled participants experienced multiple unsuccessful treatment attempts in their current episode. This likely played a role in the perception of virtual reality treatments and the modest TMS response rate. Future work is needed to optimize progressive sequencing of treatment approaches to provide rapid relief for patients suffering from symptoms of dysphoria.

Key words:Theta Burst Transcranial Magnetic Stimulation, Virtual Reality, Dysphoria

To disclose:Neuronetics: Other Financial or Material Support (Own)

Mascha van 't Wout-Frank*, Sydney Brigido, Emily Aiken, Noah Philip

Alpert der Brown University School of Medicine, Providence, Rhode Island, USA. UU.

Background:Virtual reality (VR) exposure therapy has been used to treat post-traumatic stress disorder (PTSD) based on the idea that its immersive nature promotes the emotional engagement necessary for clinical improvement. However, like non-VR exposure, VR is intense and emotionally demanding. Previously, we showed that standardized and non-customized VR Warzone scenes that capture the context of the traumatic experience distinguish veterans with PTSD from those without PTSD and reduce the severity of PTSD symptoms with high completion rates. Since clinical response to non-VR exposure is associated with inter-session habituation to trauma cues compared with in-therapy habituation, we examined inter-session and intra-session psychophysiological habituation to war zone-related standardized virtual reality exposure to assess whether standardized virtual reality specifically captures clinically meaningful learning emotions between sessions.

Methods:As part of a randomized double-blind clinical trial (NCT03372460), veterans with PTSD (n = 28) completed six 25-minute sessions of Warzone VR exposure over 2-3 weeks. In each session, participants completed the same driving scenario three times or "raced" the Iraqi or Afghan Humvee in virtual reality. Psychophysiological habituation to arousal was quantified by skin conductance reactivity to virtual reality events and was measured continuously throughout each session.

Results:To test for the presence of habituation between sessions and intrasessions and their interaction, a repeated measures ANOVA included the variables session (session 1-6, which took place over 2-3 weeks and reflects habituation between sessions) and race. (careers). 1-3 occurring within each session, reflecting habituation within the session). Mauchly's sphericity test was significant (p < 0.001) and Greenhouse-Geisser values ​​are intended to reflect adjusted degrees of freedom. The interaction term session*performance was significant (F(4,5,122,2)=2.46, p=0.04, observed magnitude 0.73), as was the main effect of the session (F(2, 9, 79.2)=3.48 , p=0.02, observed potency 0.75), but not the main effect of Run (F(1,3,35,8)=1.75, p=0.19 , observed potency 0.28). These results reflect only within-session habituation in the first VR session, but inter-session habituation in all VR sessions.

Conclusions:These data demonstrate robust cross-session habituation to non-personalized Warzone-related VR exposure. However, apart from intra-session habituation in the first VR session, no other intra-session habituation occurred. This suggests that the reduction in arousal in the context of VR trauma is due to learning over multiple sessions consistent with traditional exposure without VR. The use of standardized rather than customized virtual reality environments can provide clinical benefits without the need to highly customize the exposure experience, which in turn can improve adherence and treatment completion.

Key words:Post-traumatic stress disorder, virtual reality, safety learning, emotional arousal, skin conductivity response

To disclose:Roche: consultant (self)

Noah Philip*, Megan Senda, Yosef Berlow, Stephanie Gee, F. Andrew Kozel, Michelle Madore

Brown University e VA Providence, Providence, Rhode Island, EE. UU.

Background:Repetitive transcranial magnetic stimulation (rTMS, hereinafter TMS) is an evidence-based treatment for drug-resistant major depression (MDD). We have recently demonstrated that standard settings for treating MDD can also be effective in reducing PTSD symptoms in veterans, resulting in statistically significant and clinically significant improvements. However, previous studies of PTSD-TMS often used different protocols and device parameters that fall into the broad categories of high-frequency left-sided stimulation and low-frequency right-sided stimulation, and more recently have included theta.burst stimulation (TBS). In MDD, TBS and 10 Hz TMS, the left dorsolateral prefrontal cortex (DLPFC) is not inferior to each other, although the limited data available indicate that higher frequency stimulation appears to produce greater effects in PTSD. To this end, we examined clinical outcomes in a large multi-site registry study of TMS; Based on our previous work, we hypothesized that high-frequency stimulation would show greater efficacy than other TMS protocols.

Methods:The VA Palo Alto/Stanford Institutional Review Board has approved the procedures related to this report. Training was standardized by VA Palo Alto and data was collected using a centralized VA REDCap database. Veterans were eligible for TMS if they met the standard inclusion/eligibility criteria and other treatments were stable for approximately 6 weeks prior to stimulation and unchanged for 30 treatment sessions, usually delivered using individual head anatomy measurements (Beam/F3 ).

With regard to TMS protocols, we compared the magnitude of clinical outcomes in patients treated with FDA-approved and non-FDA-approved (ie, off-label) TMS parameters. FDA approved parameters at the time of writing include 10 Hz for Magstim, Neuronetics or Magventure systems for 4 seconds, Intertrain Interval (ITI) 11 to 26 seconds, 3000 pulses per session; Brainsway devices at 18 Hz for 2 s, 20 s ITI, 1980 pulses; and intermittent theta burst providing triplets from 50 Hz to 5 Hz, 2 s pacing with 8 s ITI, 600 pulses). All other parameters used were off-label. These included 5 Hz TMS (120% MT, 3000 pulses/session), right-side intermittent TBS (80% MT, 1800 pulses/session), 1 Hz right-side TMS (120% MT, up to 3000 pulses/session ). session). pulses/session) session) and right side 1 Hz dTMS.

Depression and PTSD symptoms were measured using the 9-item Patient Health Questionnaire (PHQ9) and PTSD Symptom Checklist for DSM5 (PCL-5); Outcomes of interest included mean and response changes (>10 point reduction in PCL, >50% reduction in PHQ9). Results were analyzed using paired-sample t-tests and missing data were excluded in list form. These data include veterans who received TMS from October 2017 to February 2022, representing an expanded cohort from previous reports.

Results:The cohort included N = 1256 veterans treated at 35 different VA-TMS clinics with usable data. Of these, n = 883 (70.3%) received FDA protocols on the label; The representation was greater in the groups that received 10 Hz (n=736), 5 Hz (n=66), iTBS on the left side (n=72) and dTMS (n=75); other protocols were more sparsely represented. There were no statistically significant differences in PTSD scores between the on-label and off-label TMS parameters, and the ANOVA showed no significant difference between the examined protocols (all ps > .1). TMS was associated with a statistically significant and clinically significant reduction in PTSD symptoms (baseline mean [SD] = 45.0 (18.3) and posttreatment mean 28.6 (19.7) p < 0.001, i.e. 1.04). There were also no statistically significant differences in MDD results between the protocols examined (all ps > .1). TMS was also associated with a significant and significant reduction in MDD symptoms (baseline score = 18.3 (5.1), post-treatment score = 10.9 (7.0) p < 0.001, d = 1.21) . Sensitivity analyzes evaluating outcomes only in those who received an adequate dose (defined as 30 sessions of TMS) did not change the results.

Conclusions:These extensive, naturalistic, and multisite data have not provided clear evidence that any single EMT protocol is superior for the treatment of PTSD. Likewise, no protocol has outperformed another for MDD. These data show at the population level that decisions about clinical parameters can be made based on patient or clinic convenience and can be balanced in terms of effectiveness. As shown above, TMS was able to produce significant and significant reductions in PTSD and MDD symptoms. Limitations are those inherent in naturalistic cohort studies that may not have captured the many changes in protocols that occurred over time. These results represent population-level data without biomarkers, and it is possible that biological data could contribute to custom parameters or targeting that could improve outcomes. Within the off-label group, individual protocols were not evenly represented, limiting statistical significance. Accelerated and neuronavigated TMS were not well represented. Ongoing studies as part of this coordinated VA network are investigating biomarkers (fMRI, EEG) and their relationship to clinical outcomes. In summary, these data do not provide convincing evidence for the superiority of any TMS protocol for PTSD or MDD, underscore existing data on the effectiveness of TMS in this patient population, and provide important information on selecting protocols to treat clinicians.

Key words:Repetitive transcranial magnetic stimulation, Post-traumatic stress disorder, Veterans

To disclose:Neurolief, Wave Neuro: other financial or material support (own)

Erica Glasper*, Shakeera Walker, Rita Beyene

Ohio State University, Columbus, Ohio, USA. UU.

Background:Adverse experiences in the first years of life increase the susceptibility to the development of mental health disorders, such as anxiety disorders, often characterized by social avoidance behaviors. In addition to reducing time spent with other people, social avoidance also involves an inability to initiate interactions. This could be a result of lower social motivation (i.e., the desire to interact) or a result of the stress experienced during social interactions. In rodents, social approach is reduced by social stressors (eg, social defeat, predator stress) and is accompanied by increased social vigilance (ie, viewing an unknown individual from a safe distance, but not approaching it). In humans, reduced social focus associated with increased social alertness may predict the development of social anxiety disorder. As interventions are successful in reducing social avoidance, determining which adverse experiences in early life are associated with social avoidance and the trajectory of these behaviors is important for early detection and better outcomes. To test the exploratory hypothesis that early negative experience of paternal absence leads to maladaptive social behavior, we used a unique model of early childhood stress in biparental rodents in which the paternal male is permanently separated from his offspring (deprivation). 🇧🇷 and examined the effects of PD on the relationships between sociability, social anxiety and social alertness in adult children.

Methods:Adult male and female mice and California mice (Peromyscus californicus) reared with PD were behaviorally evaluated for two days in a three-chamber device. Social alertness and time spent in the chamber with an unfamiliar, non-threatening, caged same-sex partner were measured during tests of sociability (day 1) and social anxiety (day 2). Statistical analyzes included two-way analyzes of variance (ANOVA) (reproduction x sex; n = 10-11/group), followed by Sidak post hoc comparisons (if applicable) and simple linear regressions. Statistical significance was reached when p ≤ 0.05.

Results:Parental deprivation had no significant effect on social vigilance in men or women during the Day 1 sociability test (2-way ANOVA; parenting x gender: F(1.37) = 2.768, p=0.10; gender: F(1.37) = 3.962, p = 0.054, reproduction: F(1.37) = 1.703, p = 0.199). However, a slightly significant interaction between parenting and gender was observed in social vigilance behavior during day 2 of the social anxiety test (2-way ANOVA; parenting x gender: F(1.37) = 4.059, p = 0.051) . Sidak's multiple comparison test showed significantly lower social arousal in PD-reared males compared to PD-reared females (adjusted = 0.03). Social surveillance was not different in control offspring (adjusted = 0.90).

Simple linear regression was used to predict social vigilance behavior during the sociability test on day 1 = 0.022, R2 = 0.61) and females (F(1,9)=11.81, p = 0.007, R2 = 0.57). Regression showed that an increase in social alertness was associated with less time on camera with the same-sex unknown conspecific. This relationship was absent in adult control offspring on day 1 of the sociability test (p >0.05, all comparisons). On day 2, when mice were again presented with the now familiar same-sex conspecific (social anxiety test), the social alert no longer explained variation in time spent with the same-sex conspecific in either group. (p > 0.05, all). comparisons).

Conclusions:These analyzes highlight the unexpected relationship between adverse parental deprivation experience early in life and social alertness during low-risk social interaction. Paternal deprivation can reinforce perceived threat mechanisms in men and women, contributing to this maladaptive behavior. Importantly, the negative relationship between social surveillance and social interaction is reduced by repeated exposure to the same species. Future work will focus on identifying ways and manipulating targets to directly link changes in social behavior to paternal male loss in a biparental rodent species. Overall, this work contributes to our understanding of the behavioral consequences of early negative experiences and may promote therapeutic interventions.

Key words:Stress in early life, social and behavioral deficits, social anxiety

To disclose:Nothing to disclose.

Kimberly Vanover*, Eve Taylor, Stephanie Parks, Jordi Serrats, Stephen Cunningham

Engrail Therapeutics, Inc., San Diego, California, USA.

Background:Generalized Anxiety Disorder (GAD) can present as excessive worry and/or tension associated with a variety of somatic symptoms that significantly interfere with daily life. Non-selective positive allosteric modulators (PAMs) of type A gamma-aminobutyric acid (GABA-A), such as benzodiazepines, are established treatments for GAD, but their use is generally limited to short-term therapy due to the risk of drug dependence. drugs and significant side effects such as sedation and cognitive and motor impairment, consequences largely mediated by the activation of GABA-A receptors that contain the alpha1 subunit. ENX-102 is a GABA-A PAM that activates neurotransmission through GABA-A receptors containing alpha2, alpha3 or alpha5 subunits while blocking 1. ENX-102 is a new drug under development for the treatment of GAD. A Phase 1 clinical study is designed to evaluate the safety, tolerability and pharmacokinetics (PK) of ENX-102 in healthy volunteers.

Methods:ENX-102 was evaluated in a single randomized, double-blind, placebo-controlled, dose-escalating study in healthy male and female subjects. The primary objective was to evaluate the safety and tolerability of ENX-102 after single oral administration of escalating doses compared to placebo. The secondary objective was to evaluate the pharmacokinetics of ENX-102 after single dose administration. After signing the written informed consent form, subjects were examined up to 28 days prior to study day 1 (dosing day). Eligible subjects were admitted to a clinical unit one day before dosing and confined for at least 4 days after dosing to monitor safety and pharmacokinetics, with an outpatient follow-up visit approximately 7 days after discharge. Eight (8) subjects per dose cohort were planned and randomized to receive ENX-102 (N=6/cohort) or placebo (N=2/cohort). Within each cohort, 2 sentinel subjects were medicated and observed for at least 24 hours before administering the remainder of the cohort. A dose escalation committee reviewed safety, tolerability, and pharmacokinetic data before escalating to the next higher dose.

Safety was assessed using adverse events (AEs), vital signs, 12-lead electrocardiograms (ECG), clinical laboratory tests (hematology, serum chemistry, coagulation, urinalysis), physical examinations, and the Observational Alert/Modified Sedation Classification. (MOAA/S) scale. Security measures were analyzed using descriptive statistics. Blood samples for pharmacokinetic analysis were collected before administration and then 15, 30, 45, 60, 90 and 120 minutes and 4, 6, 8 and 12 hours after administration. Plasma concentration-time data for ENX-102 were analyzed using non-compartmental methods. Pharmacokinetic parameters included peak plasma concentration (Cmax), time to reach Cmax (Tmax), area under the plasma concentration-time curve (AUC), and half-life (t1/2).

Results:Of the fifty-six (56) healthy volunteers who participated, 30 (53.6%) were male and 26 (46.4%) were female, and 53 (94.6%) were white, 1 ( 2.4%) Asians, 1 (2.4%)) were black and 1 (2.4%) reported being brown; none reported being Hispanic/Latino, although 19.6% declined to declare their ethnicity. Participants were randomized to receive ENX-102 or placebo (6 active: 2 placebo per cohort) in 7 cohorts, evaluating doses of 0.5, 1.0, 1.5, 2.0, 3.0, 5, 0 and 10.0 mg. All 14 patients randomized to placebo completed the study and 41/42 (97.6%) patients randomized to ENX-102 completed the study; one subject randomized to ENX-102 10.0 mg withdrew consent after completing the inpatient portion of the study and declined the follow-up visit.

There were no deaths or other serious adverse events in the study. There were no interruptions due to side effects. Treatment-emergent adverse events (TEAEs) were reported in 16/42 (38.1%) patients randomized to ENX-102 and 1/14 (7.1%) patients randomized to placebo. Consistent with a central GABAergic mechanism of action, the most frequently reported adverse events in patients receiving ENX-102 were nervous system disorders and included mild dizziness in 8/42 (19.0%), mild fatigue in 4/42 (9 .5%) and mild to moderate sleepiness in 3/42 (7.1%). Postural vertigo occurred at similar rates in subjects receiving ENX-102 (3/42, 7.1%) and placebo (1/14, 7.1%); Postural dizziness has been reported as mild to moderate in ENX-102-treated subjects and moderate in placebo-treated subjects. Other TEAEs occurred in one subject each. None of the TEAEs were serious.

There were no significant dose-related changes in physical examinations, vital signs, ECG, or clinical laboratory values. No overt sedation was observed on the MOAA/S scale.

Pharmacokinetic analyzes showed an increase in ENX-102 exposure with dose. Mean (SD) Cmax values ​​ranged from 7.013 ng/mL (1.2663) associated with the lowest dose of 0.5 mg to 95.633 ng/mL (11.7959) associated with the highest dose of 10 mg and AUC at most recent non-zero time point from 244.296 h*ng/mL (55.1034) to 4400.502 h*ng/mL (1710.469). Tmax was reached between 1 and 4 hours. The average t1/2 was around 60 hours.

Conclusions:ENX-102 has been found to be safe and well tolerated by healthy subjects. A maximum tolerated dose has not been defined. ENX-102 demonstrated predictable dose-dependent exposure with a long half-life consistent with once-daily oral administration. The data support the development of ENX-102 for the treatment of GAD. ENX-102 has advanced to a Phase 1b multiple dose escalation study.

Key words:Phase 1, GABA-A, positive allosteric modulators, generalized anxiety disorder

Disclosures: Engrail Therapeutics: Contributors (auto), Intracellular Therapies: Actions/Equity (auto), Evolution Research Group: Consultants (auto)

Jeffrey Strawn*, Jeffrey Mills, Heidi Schroeder, Zoe Neptune, Ashley Specht, Susana Keeshin

University of Cincinnati, Cincinnati, Ohio, USA. UU.

Background:The impact of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in adolescents with anxiety disorders has not been prospectively studied. In addition, there are limited prospective data on the post-acute consequences of COVID-19 (PASC), including the symptoms that constitute the neuropsychiatric syndrome with prolonged COVID-19 infection. In this context, we examined the longitudinal course of anxiety and prolonged COVID symptoms following SARS-CoV-2 infection in affected adolescents.

Methods:In December 2019, we initiated an IRB-approved longitudinal study in adolescents aged 12 to 17 years with primary DSM-5 anxiety disorders treated with duloxetine or escitalopram. At each follow-up visit, mood and anxiety symptoms during the preceding interval were assessed week by week using the Longitudinal Interval Follow-Up Examination (LIFE). Each follow-up interview included all items from the Generalized Anxiety Disorder-7 (GAD-7) scales and the Rapid Depressive Symptom Inventory (QIDS) each week, as well as a psychiatrist-rated Clinical Global Assessment of Severity (CGI- S ). ) scale. 🇧🇷 To examine differences in anxiety symptoms before and after SARS-CoV-2 infection, the distribution of the difference in mean scores of the GAD-7/QIDS and CGI-S items was calculated using a Monte simulation. Carlo de um Student's t-distribution for calculated mean pre- and post-COVID symptom scores.

Results:Twenty-six patients contributed 1308 weeks of data (1019 patient-weeks of non-COVID-19 infected patients, 289 patient-weeks of COVID-19-infected patients, and 139 patient-weeks post-COVID-19). Patients had a mean age of 14.3 ± 1.64 years (14.8% male) and 3.8% were black and were followed for 50.3 ± 30.4 weeks (range: 7 to 96 weeks, median: 55.5 weeks). All patients met criteria for generalized anxiety disorder, 19% had separation anxiety disorder, 78% had social anxiety disorder, 30% had panic disorder, 26% had ADHD, and 37% had a history of depressive disorder. All patients with COVID-19 were not vaccinated and had mild symptoms; none were hospitalized or received monoclonal antibodies. After COVID-19, anxiety symptoms significantly worsened for all GAD-7 subscales (all p < 0.001) and patients showed significant syndromic deterioration reflected in CGI-S scores (p < 0.001). SARS-CoV-2 infection was also associated with worsening of COVID symptoms in the patient (anergy, β=0.37, p<0.001; amotivation, β=0.57, p<0.001; concentration, β=0, 35, p<0.001 and irritability, β = 0.52, p < 0.001).

Conclusions:This prospective study of the longitudinal effect of COVID-19 on pediatric anxiety disorders shows that COVID-19 is associated with worsening of anxiety symptoms and an alarming 33% worsening in syndromic severity. Furthermore, these data raise the possibility that COVID-19 is associated with an excess of neuropsychiatric symptoms in anxious adolescents, constituting a long-term neuropsychiatric COVID syndrome as described in adults.

Key words:Adolescent anxiety, COVID-19, Antidepressant treatment practice

Disclosures: Myriad Genetics: Other financial or material support (automatic), AbbVie: Contract Research (automatic), MedScape, Neuroscience Educational Institute: Speakers Bureau (automatic), Yung Family Foundation: Grant (automatic), Springer Publishing: Royalties (automatic) , Cerevel: Counselor (Auto)

Jordi Serrats*, Krishna Vadodaria, Kimberly Vanover, Eve Taylor, Stephen Cunningham

Engrail Therapeutics, San Diego, California, USA.

Background:Non-selective positive allosteric modulators (PAMs) of gamma-aminobutyric acid (GABAA), such as benzodiazepines, are established anxiolytics, but their clinical use is limited due to significant side effects, which are largely mediated by activation of the GABA A receptors they contain. the α1 subunit. Various efforts have been made to generate subtype-selective GABA A modulators (α2, α3, or α5 subunits) that drive the beneficial effects of GABA modulation without the undesirable effects resulting from activation of receptors that express an included α1 subunit.

ENX-102 is a GABAA-PAM that activates neurotransmission through GABAA receptors containing α2, α3 and α5 subunits while blocking α1. We evaluated the anxiolysis potential of ENX-102 in rodent anxiety models, such as the elevated plus maze (EPM) after acute and chronic dosing, and characterized the sleep-wake electroencephalographic (EEG) profile in rats monitored by increasing doses induced by ENX -102. 102

Methods:The in vitro pharmacology of ENX-102 was determined using the SyncroPatch platform in PAM mode on human GABA A receptors α1/β3/γ2 α2/β2/γ2, α2/β3/γ2, α3/β3/γ2 and α5/β3/γ2 . 🇧🇷

Adult male SD rats (N=130; N=10 per condition) were used in the in vivo pharmacological studies. ENX-102 scored on the EPM test, which assesses anxiety. The following measurements were automatically recorded: distance walked, time spent in each arm, and entries into each arm. ENX-102 was administered orally at doses of 0.1, 0.3, and 1 mg/kg to achieve receptor occupancies of approximately 30%, 50%, and 80%, respectively, 1 hour post-dose. Acutely administered rats were also tested 24 hours after dosing. Another cohort was given once daily for 14 days and tested 1 hour after the last dose to assess the anxiolytic properties of ENX-102 after continuous guidance. Chlordiazepoxide was used as a positive control. Data were analyzed using ANOVA followed by post hoc analysis where appropriate.

Adult male SD rats (N=12 in a crossover design) were used in the pharmaco-EEG studies. The sleep stage specific pharmaco-EEG signature of ENX-102 was evaluated after oral administration of ENX-102 (0.03 mg/kg, 0.1 mg/kg, 0.3 mg/kg and 1 mg/kg ) to target a broad spectrum of receiving professions. Lorazepam (1 mg/kg) was used as a positive control. Rats were implanted with telemetry devices. Recordings began 2 hours before compound administration and were recorded continuously for 48 hours after administration. Spectral analysis included quantification of changes in spectral power for traditional EEG bands (Delta 0.5-3.9 Hz, Theta 4-7.9 Hz, Alpha 8-11.9 Hz, Beta 12-29, 9 Hz, Low Gamma 30-49.9 Hz and High Gamma 50 -100 Hz).

Sleep analysis was also performed 2 hours before ENX-102 administration and 12 hours after ENX-102 administration, and 23-25 ​​hours and 46-48 hours after ENX-102 administration. Several variables were analyzed: sleep architecture as a percentage of active wake time, quiet wake, NREM, REM, and latency to sleep onset. Dunnett's multiple comparison ANOVA was applied independently at each 15-minute interval to assess drug effects on performance of different EEG spectral bands as well as sleep stages.

All experimental protocols in animal studies were approved by the Institutional Animal Care and Use Committee and were performed in accordance with the National Institutes of Health Guide to the Care and Use of Laboratory Animals.

Results:In vitro functional activity of ENX-102 at GABA A receptors demonstrated that ENX-102 is a subtype-specific GABA A PAM. ENX-102 did not drive Cl flux in the cloned human α1/β3/γ2 GABA subtype. ENX-102 demonstrated EC50 of 0.80 nM, 0.82 nM, 2.47 nM and 0.20 nM in α2/β2/γ2, α2/β3/γ2, α3/β3/γ2 and α5 GABA subtypes, respectively / β3/γ2; and Emax of 50%, 89%, 113% and 96% for GABA A subtypes α2/β2/γ2, α2/β3/γ2, α3/β3/γ2 and α5/β3/γ2, respectively.

In vivo characterization of ENX-102 in the EPM assay showed that ENX-102 increased distance walked in open arms, demonstrating an anxiolytic-like profile. The effect was equivalent to that shown by the reference anxiolytic compound chlordiazepoxide. Chronic ENX-102 dosing showed a similar magnitude of anxiolytic effect. These data indicate potent anxiolytic activity in rodents that is maintained with chronic dosing.

The EEG profile induced in rats by the dose of ENX-102 was also examined. ENX-102 induced EEG changes suggestive of an anxiolytic profile, mimicking the EEG spectral signature that has been associated with other subtype-selective GABA modulators (see Christian et al., 2014). This EEG spectral signature can be used as an indication of central signaling pathway involvement in rodents and as a translation bridge in clinical studies.

Conclusions:ENX-102 is effective in rodents after acute and subchronic (14 days) dosing with no loss of efficacy, although it attacks the target for the entire duration of the study. Sleep-wake pattern and EEG profile analysis suggest a non-sedating anxiolytic profile of ENX-102. These data support the clinical trial of ENX-102 in anxiety-related indications.

Key words:Distress, GABA-A, positive allosteric modulators, elevated plus maze, EEG biomarker

To disclose:Engrail Therapeutics: Employee (own)

Ritchy Hodebourg*, Constanza Garcia-Keller, Peter Kalivas

Medical University of South Carolina, Charleston, South Carolina, USA.

Background:There is a strong comorbidity between post-traumatic stress disorder (PTSD) and substance use disorders. For example, a person with PTSD is 2 to 4 times more likely to have a substance use disorder than a person without PTSD. Preclinical studies have shown that both substance use and exposure to acute stress induce long-lasting neuroadaptations at glutamatergic synapses in the nucleus accumbens (NAcore), including increases in AMPA/NMDA ratio and spinal dendritic density and downregulation of the glutamate transporter. Furthermore, a stress-related (SC) stimulus, such as drug-associated cues, is capable of restoring drug-seeking behavior. Knowing that cue-induced drug seeking requires activation of NAcore matrix metalloproteinases (MMPs), we previously found that a stress CS also increased NAcore MMP-2.9 activity and burial behavior in a seeking task. Induced defensive burial (DBT). However, it is not known whether the MMP increase is mediated by MMP-2, MMP-9, or both. In this study, we first try to determine which MMP is involved in CS stress-induced burial behavior. Next, we tried to quantify MMP activity in NAcore cells specifically. We hypothesize that burial behavior is mediated by MMP-9, an MMP known to be involved in cue-induced drug seeking.

Methods:To quantify the effect of acute stress on MMP-2.9 activity, Long-Evans rats received an MMP-9 inhibitor followed by FITC-quenched gelatin immediately before 30 min of acute restraint stress or 30 min. minutes at home with the NAcore microinjected cell. To assess the role of a stress CS on MMP-2.9 behavior and activity, rats were subjected to restraint stress for 2 hours and simultaneously exposed to an odor, which became the stress CS. Control rats were exposed to the same odor in the home cage. 3 weeks post-stress, mice were pre-treated with MMP-2 or -9 inhibitors, then FITC quenched gelatin was injected into the NAcore and the effect of CS or a novel stimulus (NS) was tested on a DBT for 15 min . Burying and immobility behavior and MMP-2.9 activity were quantified. Finally, MMP-2.9 activity was quantified specifically for each cell. For this purpose, an mCherry Cre-dependent AAV virus was used to transfect medium spiny neurons (MSNs) in Cre D1 and D2 dependent mice.

Results:We found that acute stress increased MMP-2.9 activity in the NAcore. This increase is prevented by an MMP-9 inhibitor. MMP-2 and MMP-9 inhibitors prevented CS stress-induced cupping behavior without affecting immobility. However, only the MMP-2 inhibitor significantly reduced MMP activity in NAcore. Finally, we found that CS stress significantly increased MMP-2.9, particularly around D1 but not MSN around D2.

Conclusions:These results add to a growing literature suggesting that PTSD and SUDs share common neural substrates and offer new targets for the treatment of both disorders.

Key words:Matrix metalloproteinases, post-traumatic stress disorder, nucleus accumbens

To disclose:Nothing to disclose.

Briana Chen*, Holly Hunsberger, Indira Méndez-David, Denis David, Alain Gardier, Christine Ann Denny

Columbia University, New York, New York, United States

Background:Serotonin (5-HT) receptors and N-methyl-D-aspartate (NMDAR) receptors have been implicated in the pathophysiology of mood and anxiety disorders. In particular, 5-HT type 4 receptor (5-HT4R) agonists and NMDAR antagonists have been proposed as fast-acting antidepressants and prophylactic drugs that increase resistance. Here, we evaluated whether targeting both receptors by a combined dose of (R,S)-ketamine and prucalopride, a 5-HT4R agonist, would have additive effects, resulting in reduced stress-induced anxiety, behavioral distress, and hyponeophagia.

Methods:A single injection of saline, (R,S)-ketamine, prucalopride, or a combined dose of (R,S)-ketamine + prucalopride was given before or after contextual fear conditioning (CFC) stress in 129S6/SvEv mice . Administered males and females. Drug efficacy was assessed using a variety of behavioral tests, including Forced Swim Test (FST), Elevated Plus Maze (EPM), Open Field (OF), Burying Marble (MB), Suppressed Novelty Feeding (NSF) and Anxiety Contextual . Discrimination (CFD). All experiments were approved by the Institutional Animal Care and Use Committee (IACUC) of the New York Psychiatric Institute (NYSPI). The expression of c-fos and parvalbumin (PV) in the hippocampus was examined by immunohistochemistry. In general, drug effect was analyzed by analysis of variance (ANOVA), using repeated measures where appropriate. When appropriate, post hoc Dunnett, Sidak, or Tukey tests were used.

Results:A single-dose combination of (R,S)-ketamine + prucalopride (10 + 3 mg/kg) attenuated learned fear in male mice (n = 6-10 male mice per group; ANOVA; p = 0.0035) and reduced behavioral fear. distress in both sexes (n=6-10 male mice per group; ANOVA; p<0.0001; n=6-12 female mice per group; ANOVA, p<0.0001). The combined administration of (R,S)-ketamine + prucalopride exerted an additive effect in preventing stress-induced hyponeophagia in male and female mice, but not when administered separately (n=6-10 male mice per group; ANOVA, p = 0.0004, n = 6-12 female mice per group, ANOVA, p = 0.0467). Prophylactic (R,S)-ketamine + prucalopride also had an additive effect of potentiating and facilitating contextual fear discrimination in male mice (n=6-7 mice per group; p<0.0001). Combined, but not separate, administration of (R,S)-ketamine + prucalopride significantly increased neuronal activity and PV expression, as well as overlap in the ventral CA3 of the hippocampus (n = 7-8 mice per group; ANOVA; p=0.0001, p=0.0197, p=0.0178).

Conclusions:Our results demonstrate that co-targeting NMDAR and 5-HT4R with a drug combination of (R,S)-ketamine + prucalopride has additional and distinct neural and behavioral effects in reducing a variety of stress-induced anxiety, behavioral distress and hyponeophagia. Exercised behaviors in rat models of male and female stress. Simultaneous targeting of NMDAR and 5-HT4R is sufficient to increase excitatory and inhibitory signaling in specific subregions of the HPC, a brain region critically involved in processing stress and psychiatric disorders. Together, our results demonstrate the potential for using combination drug treatments to promote targeted therapies for stress-induced psychiatric disorders.

Key words:(R,S)-ketamine, prucalopride, NMDA receptor, 5-HT4 receptor, depression and anxiety

To disclose:Patent: Patent (Own)

Caroline Moreira, SA Filho Alberto, Adam Keasling, Jordan Zjawiony, Elson Costa, James Fajemiroye*

Federal University of Goiás, Goiania, Brazil

Background:Despite the attribution of the analgesic and anxiolytic properties of Salvia divinorum to a neoclerodan diterpene called salvinorin A (SA), the limited pharmacological profile and lack of clinical applications of SA support the preliminary selection of its C-fused heteroaromatic analogue (22) [ 2 -O-salvinorin B benzo[b]thiophene-2-carboxylate (AK-1402)] in mouse models of nociception and anxiety when evaluating the possible mechanism of action.

Methods:Acute oral administration of AK-1402 (1, 3 or 10 mg/kg), morphine (MOR 5 mg/kg), diazepam (DZP 1 mg/kg) or vehicle 10 mL/kg in male and female Swiss mice [5 weeks with weight = 25 ± 3 g; n = 8 (4 mice per sex) randomized to treatment groups for acetic acid-induced writhing, formalin-induced hindpaw licking, hotplate thermal reaction, and aversive reaction of elevated plus maze (EPM) and light box -dark (LDB). In addition, mice were treated intraperitoneally with naloxone (NAL 3 mg/kg; non-selective opioid receptor antagonist), naloxonezine (Nalzine 10 mg/kg; selective μ-OR antagonist) and nor-binaltorphimine (nor-BNI 10 mg/kg). 🇧🇷 more selective ĸ-OR antagonist) or vehicle prior to oral administration of AK-1402 10 mg/kg, MOR 5 mg/kg, DZP 1 mg/kg or vehicle 10 mL/kg and behavioral assessments. In all experimental procedures, the NIH guidelines for the care and use of laboratory animals, approved by the Ethics Committee of the Federal University of Goiás (protocol number 104/08), were followed. Data were submitted to ANOVA followed by post hoc Dunnett or Bonferroni tests and expressed as mean ± SEM (p < 0.05 was considered statistically significant).

Results:Oral administration of AK-1402 (3 and 10 mg/kg) and MOR 5 mg/kg reduced writhing activity [F(4,39)=61.6], licking behavior in the first phase of formalin [F (4.25) = 19.8 , p<0.05] and increased latency for response to thermal stimulation on a hot plate [F(4.35)= 8.6, p<0.05], demonstrating an antinociceptive property . As with DZP 1 mg/kg, increased duration and open-arm entry of EPM [F(4,35)=12.5 and F(4,35)=8.3, respectively; p < 0.05] and the time of transition and permanence in the LDB bright zone [F(4, 35) = 10.1 and F(4, 35) = 9.3, respectively; p<0.05] suggests attenuation of the aversive-type response by AK-1402 at a dose of 10 mg/kg. Blockade of antinociceptive and anxiolytic properties after pretreatments with NAL, Nor-BNI and/or FLU suggests the involvement of opioid receptors and benzodiazepine sites in AK-1402 activities.

Conclusions:The antinociceptive and anxiolytic effects of AK-1402 are promising and require further pharmacological characterizations.

Key words:Salvinorin A, AK-1402, behavior model, opioid system, GABAergic system

To disclose:Nothing to disclose.

Teresa Daniels*, William Lewis-de los Ángeles, Brooke Hjelm, Emily Zitkovsky, Audrey Omidsalar, Marquis Vawter, Audrey Tyrka

Brown University, Bradley Hospital, Riverside, Rhode Island, EUA. UU.

Background:Growing evidence suggests that mitochondria respond to psychosocial and environmental stressors. A recent study found increased mitochondrial DNA (mtDNA) deletions in the postmortem brains of people with psychiatric disorders, but no previous work has examined the effects of early childhood stress (ELS) and adult health behaviors on mtDNA deletions. . This study evaluated mtDNA deletions, diet, and cardiometabolic risk in peripheral blood mononuclear cells (PBMC) in healthy young adults with and without ELS.

Methods:Participants (N = 181; 69% female) aged between 18 and 40 years were recruited from the community. Participants with ELS (n = 108) experienced childhood abuse and parental loss. Controls (n = 73) did not experience abuse, bereavement or psychiatric disorders. Standardized interviews and self-reports assessed demographics, adversities, psychiatric history, cardiometabolic risk factors, and dietary intake using the Healthy Eating Index. PBMC were isolated for sequencing mtDNA deletions. The splice-break pipeline with long-distance PCR and next-generation sequencing was used to quantify mtDNA deletions with statistical control for depth of coverage. The mtDNA deletions were log-transformed for analysis due to asymmetry.

Results:In a linear model adjusted for age, gender, and depth of coverage, participants with ELS showed significantly more single mtDNA deletions (F(4,176)=19.2, p<0.001) than participants without ELS. Current psychiatric disorders, adult stressors, and current perceived stress were associated with deletions (p < 0.05), but did not represent associations of ELS with single mtDNA deletions. A healthier diet was associated with less well-defined mtDNA deletions (p =0.046) in a linear model adjusted for age, sex, and depth of coverage, although diet was not responsible for the association of adversity and deletions in childhood. of mtDNA (p <0.001). There was no association between a composite metabolic risk score and burden of mtDNA deletion (p = 0.50).

Conclusions:In this sample, participants with ELS had a greater number of clear deletions regardless of psychiatric status. Furthermore, diet, but not cardiometabolic risk, predicted mtDNA deletions in healthy young adults. These preliminary results add to recent evidence suggesting that mtDNA is influenced by childhood adversities, psychiatric disorders, and health behaviors. Next steps include a more in-depth assessment of relationships to mitochondrial structure and function, metabolic hormones, and the nature and timing of adversity.

Key words:Mitochondrial DNA, Early Life Stress (ELS), Nutrition

To disclose:Nothing to disclose.

Michael Lewis*, Eylul Akman, Scott Rauch, Isabelle Rosso

McLean Hospital, Harvard Medical School, Belmont, Massachusetts, EUA.

Background:Post-traumatic stress symptoms (PTSS) are characterized in part by pathological anxiety, anxiety and stress reactivity (FASR). Certain aspects of the FASR are indexed with physiological measures of acute conditioned fear response and self-reported measures of dispositional fear reactivity. Elevated physiologic or self-reported FASR has been observed in some but not all PTSS specimens and may contribute to variability in clinical presentation and response to treatment.

The unconditional physiological response (UCR) to a naturally aversive stimulus may contribute to individual differences in FASR. Studies in rodents, healthy humans, and those with anxiety-related disorders have found that the UCR predicts the physiological response to a conditioned fear signal during fear acquisition. In a recent study of fear-potentiated Schreckle (FPS) in trauma-exposed individuals with low PTSS (Kreutzmann et al., 2021), UCR predicted FPS for conditioned fear and safety cues during acquisition. Some previous studies have found that the physiological response to stress is related to self-reported FASR. In a transdiagnostic study of anxiety and anxiety disorders (Marin et al., 2020), UCR predicted a self-reported composite score of dispositional stress reactivity. Here, we extend previous work by testing the association of UCR with physiological and self-reported anxious reactivity in a trauma-exposed sample with a PTSS severity continuum. We hypothesize that higher UCR would be positively correlated with FPS on conditioned fear signals during acquisition and extinction, with FPS on conditioned security signals during acquisition and extinction, and with self-reported dispositional FASR. We also examined associations of UCR with PTSS severity.

Methods:Participants were 79 trauma-exposed adults (61 women) with a PTSS severity continuum. PTSD severity was quantified as a total score on the Physician Administered PTSD Scale (CAPS) for DSM-5. A self-reported composite anxiety, anxiety, and stress reactivity (FASR) score was obtained by averaging the z-scores of four self-reported measures indicative of different aspects of dispositional FASR and previously associated with PTSS and anxiety conditioning: Anxiety Survey Schedule – II, Anxiety Sensitivity Index-3, State-Trait Anxiety Inventory - Trait Anxiety Scale and 10-item Connor-Davidson Resilience Scale. FPS recorded during capture and scary erasure. The auditory startle probe was a burst of white noise. The unconditioned stimulus (US) was a breath of air in the larynx and the conditioned stimuli were bicolor shapes. The fear conditioned signal (CS+) was coupled to the US during acquisition and the security conditioned signal (CS-) was never coupled to the US. Acquisition consisted of 12 studies with each CS, with US following each CS+ study. Extinction consisted of 16 trials for each CS type. Average FPS for UCR was calculated using the 12 US submissions during acquisition. Average FPS for CS+ and CS- during acquisition and extinction were calculated after omitting the first trial of each CS type for each phase. Six separate linear regressions tested the correlation of UCR with FPS for CS+ during acquisition, FPS for CS+ during absorbance, FPS for CS- during acquisition, FPS for CS- during absorbance, FASR score, and total CAPS. All analyzes were performed with and without sex as a covariate.

Results:UCR was positively correlated with CS+ during acquisition (R2=0.24; p<0.0001), CS+ during extinction (R2=0.13; p=0.0028), CS- during acquisition (R2 = 0 .14; p = 0.0.0.0.0, absorbance (R2 = 0.21; p < 0.0001) and FASR (R2 = 0.15; p = 0.0004). UCR did not correlate with total CAPS (R2 = 0.03; p = 0.1352 All significant correlations survived the Bonferroni correction and remained significant for Bonferroni when gender Female gender was associated with higher total CAPS scores (B = 0.66, p = 0.0184), but this association did not survive Bonferroni's correction.

Conclusions:Higher UCR was associated with higher conditioned FPS in four different states (CS + acquisition, CS + extinction, CS acquisition, CS extinction) and with a composite measure of self-reported dispositional FASR in this sample exposed to trauma with a severity continuum PTSS. Thus, in trauma-exposed individuals, an increased UCR to naturally aversive stimuli may result in an increased physiological fear response to a wide range of conditioned stimuli and an increased tendency to feel anxious and anxious in response to stress. Conditional anxiety erasure is the mainstay of prolonged exposure therapy in PTSD, and the inability to suppress anxiety in the presence of conditioned safety cues is believed to represent a distinct phenotype of PTSD in terms of response or resistance to treatment. Therefore, future studies are needed to determine whether an increased UCR predicts differences in treatment response in PTSD.

Key words:Post-traumatic stress disorder, fear-potentiated shock, fear conditioning and extinction, unconditioned responses, anxiety and stress

To disclose:Nothing to disclose.

Meghna Ravi*, Sriya Karra, Tanja Jovanovic, Jennifer Stevens, Abigail Powers, Vasiliki Michopoulos

Emory University School of Medicine, Atlanta, Georgia, USA

Background:Neighborhood poverty is associated with exposure to chronic stressors, including environmental stressors such as noise and pollution, and traumatic events such as police violence and other violent crimes. Recent work by our group has shown that neighborhood poverty is associated with worse post-traumatic stress disorder (PTSD) symptoms in both chronically traumatized black women and acutely traumatized multiracial men and women. PTSD is also characterized by dysregulation of autonomic function. For example, after a traumatic event, people with PTSD take longer to adjust to a startle sound than people without PTSD. Additionally, several studies show greater startle in people with PTSD compared to people without PTSD. Despite the association between neighborhood poverty and PTSD symptoms, little is known about how neighborhood poverty is related to dysregulated psychophysiological functioning in PTSD. Thus, in the current study, we found associations between neighborhood poverty and acoustic startle in a fear-potentiated startle paradigm. We hypothesized that people living in areas with high poverty rates with high levels of PTSD symptoms would experience the highest level of distress. We also examined the interactions of PTSD symptom subgroups with neighborhood poverty rates at alarming levels.

Methods:Participants (N = 64, 70% women) were enrolled in the waiting rooms of a large public hospital in Atlanta, GA between 2013 and 2014. Participants were recruited from medical clinics, including primary care or obstetrics and gynecology waiting rooms . The sample consisted of 93.8% black, 3.1% white, 1.6% Latino and 1.6% brown. Basic sociodemographic information was collected, including the participant's zip code of residence. PTSD symptoms were assessed using the Modified PTSD Symptom Scale (PSS). Neighborhood poverty was assessed using the 2014 Five-Year American Community Survey, an annual survey that identifies sociodemographic information (eg, poverty) for a specific area in the United States. Neighborhood poverty was defined as the percentage of people living below the federally defined poverty line in a participant's zip code. Finally, startle severity was determined using an acoustic startle paradigm. Startle magnitude was defined as the mean intermittent electromyogram (EMG) response to 106 decibel white noise probes over 12 task trials. Moderation analyzes were used to determine the effect of neighborhood poverty on distress levels and whether there was a moderating role for PTSD symptoms.

Results:The model with full PTSD symptoms as a moderator accounted for 13.45% of the variance in shock severity, F(3.60)=3.11, MSE=1080.49, p=0.03. Neighborhood poverty significantly predicted startle levels, while living in more poverty-stricken areas predicted lower startle levels (B = -132.27, SE = 54.56, P = 0.02). There was also an interaction between neighborhood poverty and PTSD symptoms in level of distress (B = 6.19, SE = 3.15, ΔR²= 0.06, p = 0.05). Follow-up analyzes were performed to determine the conditional impact of PTSD symptoms. Results showed that the effect of neighborhood poverty on the degree of startleness was significant only at the 16th percentile of PTSD symptoms (B = -136.08, SE = 52.39, P = 0.02), but not at the 50th percentile. (B = -70.42, SE = 39.49, p = 0.08) or 84th percentile for PTSD symptoms (B = 13.70, SE = 53.09, p = 0.80). In the symptom subgroup analyses, the model with overarousal symptoms as a moderator accounted for 11.88% of the variance in startle severity, F(3.60)=2.70, MSE=1100.11, p=0, 05. In this model, neighborhood poverty significantly predicted level of fear (B = -124.33, SE = 56.70, P = 0.03), although the interaction between arousal symptoms and neighborhood poverty was not significant (B = 14.88, SE = 8.69, ΔR²= 0.04, p = 0.09). For intrusion symptoms, the model accounted for 7.86% of the variation in shock force and was not significant, F(3.60)=1.7, MSE=1150.34, p=0.18. Finally, the model of avoidance and daze symptoms predicted 12.54% of the variation in collision force, F(3.60)=2.87, MSE=1091.84, p=0.04. Neighborhood poverty significantly predicted level of fear (B = -132.77, SE = 53.11, P = 0.02) and the interaction between avoidance and sedation symptoms and neighborhood poverty was significant (B = 14.04, SE = 6.80, ΔR²= 0.06, p = 0.04). Follow-up analyzes revealed that neighborhood poverty was most common in the 16th (B = -132.77, SE = 53.11, p = 0.02) and 50th (B = -83.63, SE = 40, 97, p = 0.05) avoidance and intoxication percentiles predicted symptoms at an alarming rate, but not at the 84th percentile of avoidance and intoxication symptoms (B=2.02, SE=48.97, p=0.97).

Conclusions:Our results show that neighborhood poverty is associated with silent terror only in people with few PTSD symptoms. This effect appears to be driven by the cluster of PTSD numbing and avoidance symptoms. People living in areas with high poverty rates may be more accustomed to loud noises, possibly due to increased exposure to loud noises in their everyday environment, leading to a reduced response to acoustic shock probes. This habituation may disappear when a person has more severe PTSD symptoms. Overall, the results suggest that neighborhood poverty may affect basic autonomic functions. Future studies should further explore the role of different types of PTSD symptoms and their interaction with neighborhood poverty in affecting psychophysiology.

Key words:Acoustic shock, PTSD, neighborhood poverty

To disclose:Nothing to disclose.

Vasiliki Michopoulos*, Susie Turkson, Paul Howell, Igho Ofotokun, Tanja Jovanovic, Gretchen Neigh

Emory University School of Medicine, Atlanta, Georgia, USA

Background:People living with HIV often experience trauma throughout their lives, increasing their individual risk of developing post-traumatic stress disorder (PTSD) and psychophysiological hyperarousal, including deficits in calming anxiety. Additionally, marginalized and underserved black women living in urban settings often experience high levels of trauma, suffer from chronic PTSD, and are at increased risk of HIV infection. Because evidence-based PTSD treatments such as B. prolonged exposure are dependent on anxiety cessation, it is important to understand how HIV serological status interacts with PTSD to influence anxiety cessation. We hypothesized that people with HIV and PTSD would have greater deficiencies in calming anxiety. Furthermore, it is important to understand the biological mechanisms by which HIV and PTSD may influence anxiety eradication processes. Estradiol (E2) and its receptors, estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ), influence the neurobiological processes underlying the extinction of anxiety. More specifically, preclinical and translational studies in women show that limbic brain regions critical for fear erasure and learning are densely populated with ERα and ERβ, demonstrating that E2 influences fear erasure processes. Therefore, in the present study, we also evaluated the effects of HIV and PTSD on the relationship between peripheral ERα gene expression and peripheral ERβ gene expression. Our hypothesis is that both HIV and PTSD would be associated with differences in the proportions of ERα to ERβ gene expression.

Methods:Women (18-65 years) recruited from the Women's Interagency HIV Study (WIHS) in Atlanta, GA (n=70, 26 HIV-negative, 44 HIV-positive) gave informed consent and underwent a semi-structured assessment interview ( Traumatic Events Inventory; TEI) and exposure to childhood trauma (Childhood Trauma Questionnaire; CTQ) and PTSD using the PTSD Checklist for DSM-5 (PCL-5). Participants were also subjected to a fear-enhanced shock (FPS) paradigm to assess fear extinction. Blood samples were collected within two weeks of the FPS paradigm to assess peripheral ERα and ERβ gene expression. A ratio of ERα to ERβ gene expression was calculated. ANCOVAs were performed to assess the effects of HIV, PTSD and their interaction on extinction anxiety and ERα/ERβ expression controlled for age, income, education and trauma exposure in adults.

Results:PTSD diagnosis (p = 0.021; η2 = 0.088) and HIV status (p = 0.046; η2 = 0.067) were associated with deficits in percent reduction in anxiety cessation. There was also a significant interaction of HIV status and PTSD diagnosis (p=0.023; η2=0.082) on extinction anxiety, as HIV was associated with decreased extinction anxiety only in women diagnosed with PTSD (p= 0.026; partially eta2 = 0.078). Although there were no main effects of PTSD or HIV on ERα/ERβ expression, there was a significant interaction between PTSD and HIV (p = 0.006; η2 = 0.142). ERα/ERβ expression was significantly lower in women without PTSD and with HIV (p = 0.007) and women with HIV and without PTSD (p < 0.001) compared to women without HIV or PTSD.

Conclusions:Our results suggest that HIV affects the psychophysiology of anxiety in women diagnosed with PTSD, demonstrating impairments in anxiety extinction. Given the use of prolonged exposure as a prominent evidence-based therapy for PTSD, these findings are clinically relevant, suggesting that HIV may compromise the effectiveness of such treatment in women living with HIV. Our results also suggest that HIV and PTSD affect ERα/ERβ expression in females, but not synergistically. Future studies are needed to determine how changes in ERα/ERβ expression may contribute to deficits in anxiety relief in women living with HIV, including inflammatory pathways associated with psychophysiological hyperarousal in people exposed to trauma.

Key words:PTSD, HIV, fear of extinction, estrogen receptor, women's mental health

To disclose:Nothing to disclose.

Abigail Powers*, Catherine Abrams, Elizabeth McAfee, Shimarith Wallace, David O'Banion, Rebecca Hinrichs, Vasiliki Michopoulos, Jennifer Stevens

Emory University School of Medicine, Atlanta, Georgia, USA

Background:Risks associated with trauma and post-traumatic stress disorder (PTSD) are passed down from generation to generation, but little is known about the early pathways of risk or resilience associated with maternal PTSD. Childhood is a critical period for socio-emotional development. The emotional connection (EC) between mother and child is particularly important for the infant's secure attachment and ability to regulate stress. Infant cardiac reactivity and low vagal tone, as measured by heart rate (HR) and respiratory sinus arrhythmia (RSA), are significantly influenced by parental behavior and may be an important early biomarker of post-infant vulnerability risk. Furthermore, increased sympathetic arousal is a biomarker of PTSD, and maternal emotional reactivity may affect a mother's ability to respond to her child's needs. However, previous studies have not examined how mother-infant CD is related to maternal-infant stress response or its relationship to maternal PTSD. Therefore, examining physiological stress response patterns in newborns and their mothers in a sample of women with high levels of PTSD symptoms and trauma exposure will contribute to our understanding of the potential ways in which maternal PTSD affects development. -risk children for negative results.

Methods:In the current pilot study, maternal PTSD symptoms, mother-infant emotional connection (MC) and mother-infant stress response to the Immobile Two-Sided Paradigm (DSFP, 4m) were measured in 20 mother-infant dyads (mean of mother age = 27; infant) measured = 4 months; 91% Black or African American) recruited from an urban safety net hospital with high exposure to trauma and PTSD (45% with a probable diagnosis of PTSD). DSFP is a laboratory stress task used to assess the infant's response to maternal distancing. The dyads completed a behavioral task in which they rated baseline EQ and post-stress EQ using the Welch Emotional Attachment Scale, which includes measurement of attractiveness, voice, face, and sensitivity scales, and a total EQ score. PTSD symptoms were assessed using the DSM-5 PTSD Checklist. The child's respiratory sinus arrhythmia (RSA) and heart rate (HR) were measured during DSFP. Maternal skin conductance (SCR) response during DSFP was also obtained from a subsample of participants (n = 8). Bivariate correlations between maternal PTSD, mother-infant CO at baseline, and physiological response to stress were analyzed. For the baby's stress response, baseline, early recovery, and last recovery points were used. Bivariate correlations between PTSD symptoms and post-stress EC were also performed.

Results:Bivariate correlation analyzes showed that higher mother-infant EC during the onset of the first phase of DSFP recovery (r = 0.48, p = 034), but not at baseline (r = -0.15, p = ) , was significantly associated with greater infant RSA response was associated with 0.53) or final recovery (r = 0.33, p = 0.19). There were no significant associations between mother-child CD and CF. Furthermore, mother-infant EC was inversely proportional to the level of maximum maternal skin conduction response during DSFP (r=-0.85, p=008, n=8). No significant correlative associations were found between PTSD symptoms and mother-infant CD or infant ARS or CF at baseline. However, higher PTSD symptoms were associated with lower mother-child EQ after exercise for the facial and sensation subscales (r = -0.54, p = 0.031 and r = -0.52, p = 0.041;n= 16).

Conclusions:The results suggest that CD in mother-infant dyads is related to how mothers and their babies respond to stress and point to an important potential pathway through which intergenerational trauma and risk or resilience can occur.

Key words:Post-traumatic stress disorder, intergenerational transmission of trauma, psychophysiology

To disclose:Nothing to disclose.

Ida Fonkoue*, Katherinne Fox, Sayra Medina Bañuelos, Abigail Powers, H. Drew Dixon, Rachel Gluck, William Umpierrez, Tanja Jovanovic, Thaddeus Pace, Kathryn Cullen, Vasiliki Michopoulos, Charles Gillespie

University of Minnesota School of Medicine, Shoreview, Minnesota, USA.

Background:Higher rates of trauma exposure are strongly associated with poverty. Women exposed to trauma are twice as likely to develop post-traumatic stress disorder (PTSD) than men. Previous research suggests that the presence of PTSD is associated with poor sleep and an increased risk of cardiometabolic disease. However, given the potential link between poor sleep quality and cardiometabolic disease, it is unclear whether sleep disruption is the mechanism by which PTSD leads to increased risk of cardiovascular disease. In this study, we examined the impact of PTSD diagnosis and symptom severity on cardiovascular and autonomic responses to acute psychological stress. In addition, we examined the effect of sleep quality and comorbid depression on these responses. We hypothesize that women diagnosed with PTSD have elevated blood pressure, heart rate, and sympathetic responses to the Trier Social Stress Test (TSST) and that these responses are moderated by sleep quality.

Methods:To test this hypothesis, we recruited 74 black women (aged 31 to 63) with a history of trauma and type 2 diabetes from a large municipal hospital in the southeastern United States. We measured cardiovascular and sympathovagal response during TSST in women with (n = 45) and without (n = 29) a current diagnosis of PTSD. Categorical diagnosis of PTSD and severity of PTSD symptoms were assessed using the Physician Administered PTSD Scale (CAPS), severity of depressive symptoms using the Beck Depression Inventory (BDI), and sleep quality using the Pittsburgh Sleep Quality (PSQI). Baseline systolic and diastolic blood pressure (BP) was measured using the automated SphygmoCor. Participants completed the 20-minute Tier Social Stress Test (TSST) and sat in a quiet room before and after the standardized psychosocial stress test. Heart rate (HR) and low-to-high-rate ratio (LF/HF) were obtained using a 3-lead ECG measured before, during, and after the TSST. Pearson's correlation was used to examine the relationship between CAPS, BDI, and PSQI scores. PA, HR, and LF/HF reactivity was analyzed using repeated measures ANOVA with time within the factor and PTSD diagnosis between the factors. PSQI and BDI were covariates in the analysis.

Results:We found a significant correlation between PSQI severity and CAPS (r = 0.47, p = <0.001) and between PSQI and BDI (r = 0.58, p = <0.001). The heart rate response to the TSST was significantly greater in the PTSD group than in the non-PTSD group (time, p=<0.001; group, p=0.02) The LF/HF response was also significantly greater in those with PTSD compared with those without (Time , p=0.46; group, p=0.05) Systolic blood pressure response did not differ between groups (time, p=<0.001; group, p= 0.22). Given the strong correlation between PSQI and BDI, we decided to control for one of the two variables in repeated measures ANOVA was selected based on the literature supporting the association between sleep deprivation and an exaggerated sympathetic response to acute stress in women. Reactivity between groups was affected.

Conclusions:Our results show that PTSD status is associated with heart rate hyperresponsiveness and autonomic imbalance during a standardized psychosocial stressor in this sample of traumatized black women with type 2 diabetes. Furthermore, we found that sleep quality moderates this response. This suggests that sleep disturbances are a feature of PTSD and may be the factor leading to the reported sympathetic hyperactivity of the acute stress described in PTSD. Therefore, improving sleep quality can serve as a target for interventions aimed at reducing the cardiovascular risk associated with PTSD.

Financing: Supported by R01MH099211 (CFG).

Key words:PTSD, women, sleep, heart rate variability, heart rate

To disclose:Nothing to disclose.

Zachary Pennington*, Alexa LaBanca, Zhe Dong, Patlapa Sompolpong, Denise Cai

Icahn School of Medicine at Mount Sinai, New York, New York, United States of America

Background:Acute severe stress can produce a variety of changes in anxiety and anxiety-like behaviors, including defensive responses to stress-associated stimuli, increased responses to novel aversive events, and increased anxiety-like behaviors. It remains to be seen whether these different high-stress outcomes arise through plasticity in a common circuit or whether different circuits support the different high-stress outcomes. Answering this question is critical to understanding how to mitigate the pathological consequences of stress. Here, using a combination of region-specific protein synthesis inhibition, chemogenetics, and activity-dependent cell labeling, we show that stress-induced plasticity in the ventral hippocampus (VHC) and basolateral amygdala (BLA) supports dissociable stress events. severe.

Methods:Experiment 1 examined the role of stress-induced protein synthesis in HCv and BLA on hindsight behavior. Mice were subjected to a severe acute stressor, whether or not they received 3-meter electrical shocks, and protein synthesis in both structures was blocked shortly afterwards. One week later, associative fear of the stressor was assessed by placing the animals back in the stressful environment and freezing was measured, fear-like behavior was assessed in a light-dark test, and learning about new subjects was assessed. The use of aversive events were exposed to nothing more than auditory stressors in a separate conditioning chamber. Next, Experiment 2 evaluated how BLA and HCv support the expression of post-stress behavior changes. An identical behavioral procedure was used as in Experiment 1, but chemogenetics was used to inhibit HCv or BLA during the expression of post-stress behavioral phenotypes. Finally, Experiment 3 used a transgene activity-dependent labeling approach to permanently label stress-sensitive cells and then examined their reactivation in response to subsequent events using immunohistochemistry. n = 8-12/group. Male mice were used for these experiments.

Results:In Experiment 1, blocking stress-induced protein synthesis in the BLA significantly reduced subsequent associative freezing in the context of the stressor and mitigated heightened responses to a novel stressor, but had no effect on anxiety-like behavior in the animals themselves. In contrast, blocking stress-induced protein synthesis in HCV attenuated changes in anxiety-like behavior but had no impact on responses to novel stressors and had minimal impact on associative freezing. In Experiment 2, using chemogenetics, we showed that neuronal activity in BLA and HCv make similar dissociative contributions to the expression of these post-stress phenotypes. Finally, in Experiment 3, we found that stress-sensitive ensembles in BLA (but not in HCv) are more likely to be reactivated by new stressors, suggesting that stress-induced plasticity specifically within this cell population supports an increased response to new stressors. stressors.

Conclusions:Taken together, these results indicate that plasticity in separate BLA and vHC circuits supports the differential effects of stress on behavior, and ongoing research aims to further elucidate the unique role of stress-sensitive assemblies. Crucially, these results suggest that the effects of severe stress are biologically distinct. If true, this may suggest that interventions targeting one of these post-stress phenotypes (eg, associative memories) in conditions such as PTSD may target other post-stress phenotypes (eg, anxiety). Furthermore, by targeting specific cells within these networks that are activated by stress, we could mitigate post-stress phenotypes.

Key words:Fear, anxiety, amygdala, hippocampus

To disclose:Nothing to disclose.

Thomas Kash*, Olivia Hon

University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, EE. UU.

Background:Anxiety disorders affect approximately one-third of the population, and a central symptom of anxiety and trauma-related disorders is excessive and generalized anxiety. While detecting and responding to threats that predict danger is essential to survival, constant preoccupation with future threats can become inappropriate. Recent work suggests that the predictability of whether and when danger will occur plays a crucial role in the development of pathological anxiety. Recent studies in rodents have shown that an unpredictable but unpredictable threat affects the bed nucleus of the stria terminalis (BNST), a part of the enlarged amygdala that has long been studied in relation to stress, anxiety and substance abuse.

Methods:We used several approaches to investigate this question. To determine whether CRF in BNST regulates fear and antecedent behavior, we used viral clearance of CRF in conjunction with behavior in the mouse brain. To determine activity profiles of neurons and modulators, we used fiber photometry and miniscope recordings in mice.

Results:First, we found that partially reinforced (PRF) but not fully reinforced (FRF) fear conditioning resulted in an exaggerated auditory startle response in men but not in women. We then used multiregional fiber photometry to characterize the BNST cell body and terminal dynamics in the periaqueductal gray matter, a midbrain structure that regulates adaptive motor responses. We found that during fear conditioning, BNST cell body and terminal activity did not differ between fear groups, but differences were observed 24 hours later during fear recall. Interestingly, the magnitude of BNST responses during conditioning was positively correlated with memory freeze behavior in PRF mice but not in FRF mice.

We then became curious about the modulation signaling that drives these behaviors. The extensive work of Mike Davis and others over the years has shown that the neuropeptide corticotropin releasing factor (CRF) plays an important role in this behavior. Therefore, our aim was to determine the role of BNST-CRF neurons in partially heightened anxiety in male and female mice. Using a floxed CRF transgenic line, we found that CRF knockdown in BNST selectively increased PRF in females but not in males. We then implanted GRIN lenses and used miniature head-mounted microscopy to record individual BNSTCRF cells during behavior. We found that post-conditioning BNSTCRF activity in both sexes was greater in partially-enhanced fearful mice than in fully-enhanced fearful mice, and that cells responded differently across groups and sexes during fear recall. Finally, using fiber photometry in conjunction with a new CRF biosensor, we identified differences in CRF release in PAG, but not in BNST, during fear recall between groups.

Conclusions:Overall, we found sex-specific effects of BNSTCRF signaling on partially and fully increased anxiety, suggesting potential sex-dependent treatment strategies based on CRF modulation. In particular, we found that deletion of BNST CRF in male mice exposed to a more reliable fear leads to an increase in postfear startle, suggesting that fear-evoked release of CRF limits arousal.

Key words:Amygdala, neuropeptides, auditory startle response

To disclose:Nothing to disclose.

Erin Hisey*, Emily Newman, Kerry Ressler

Harvard Medical School, McLean Hospital, Belmont, Massachusetts, EUA.

Background:Adolescence is a time of monumental cognitive and neurobiological changes. Trauma during this time can, in turn, disrupt normal brain development and lead to lifelong psychiatric disorders. While there are models for early life neglect in rodents, there are almost no models for early life trauma. To better understand the neurobiological basis of early childhood trauma in the adult brain, we developed a model of chronic social defeat in male mice.

Methods:Chronic Adolescent Social Defeat Stress (aCSDS): On the first day of aCSDS, a male C57BL/6J (C57) experimental mouse (P27+/-2 days) is placed directly into the territory of an adult male (>8 weeks old). Resident CFW a 3-minute aggressive encounter (ends after 30 bites). After the aggressive encounter, the experimental C57 mouse is housed with that resident for 24 hours until the aggressive encounter the next day. This defeat and housing process is repeated with a new inhabitant every day for 10 days. Undefeated control C57 mice are housed in shared cages identical to those used for defeat, along with an unknown control C57 mouse. On day 10 of aCSDS, defeated and control C57 mice are housed side by side in shared cages allowing olfactory and visual contact until adulthood.

CFW Male Open Field Social Interaction (OFSI): After 1 hour of acclimatization in the test room, male C57 mice (P50 for late adolescence tests, P70 for adult tests) are placed in front of a wire plate. black inverted in a large (44 x 44 cm) stadium. After 150 seconds of exploring the arena and the cup empty, C57 is placed back in the arena with the cup now containing a new non-aggressive CFW man inside and allowed to explore for 150 seconds. All interactions are recorded and evaluated with Ethovision. The social interaction index is calculated as the time spent with an empty glass divided by the time spent with the glass containing a CFW.

Home Cage Social Interaction with Ovariectomized CFW Females (HCSI): Adolescent male C57 mice (~P50) remain in their home cage and an ovariectomized CFW female is placed in the cage for 90 seconds. If either a male or a female bites, the interaction immediately ends and the female is replaced by another female. The interaction is recorded at 30 fps and then analyzed for specific behaviors using DeepLabCut.

Whole brain c-fos imaging: After OFSI, mice are placed in an empty, clean cage in a quiet room for 1 hour and then perfused with 1X PBS followed by 4% PFA. Brains are removed and placed in PFA overnight and then stored in 0.02% sodium azide-PBS. Only brains without redness or visible damage were used for tissue purification, followed by c-fos labeling and whole brain imaging (LifeCanvas Technologies).

Results:After chronic exposure to defeat in early adolescence, mice exhibit strong social avoidance that is maintained through late adolescence and into adulthood (t-test for OFSI proportion of social interaction with non-aggressive CFW males; n = 40 defeated, 38 male control mice; in late adolescence (~P50), p<0.0001, in adulthood (>P70), p<0.0001). This social avoidance behavior also generalizes to female mice of the same lineage as those used as aggressors during defeat (HCSI with female CFW at ~P50, characterized with DeepLabCut, n = 14 defeated, 14 controls; t-test for reductions in monitoring (p<0.001) and contact (p<0.01), increased defense (p<0.001) and freezing (p<0.05) in defeated mice compared to controls). Re-exposure to a non-aggressive male mouse in adulthood results in a dramatic increase in c-fos activity with changes in network connectivity in the brains of defeated male mice when young, as shown in the images. of c-fos of the whole brain. Significant increases in c-fos expression compared to control mice were found in the hippocampus (CA3), medial and lateral entorhinal cortex, and anterior insula (n = 6 knockout brains, 6 control brains, t-test showing compare defeated and depleted brains). control, p < 0.05).

Conclusions:Our aCSDS model generates robust and long-lasting deficits in social interaction that allow us to examine the neural circuits underlying avoidance behavior, a hallmark of neuropsychiatric disorders such as generalized anxiety and PTSD, following the stress of social defeat in children and adolescents. One of the strongest areas of activation after adult social interaction in young defeated mice is CA3, a region involved in pattern completion. Interestingly, changes in hippocampal volume and connectivity are among the strongest findings in human imaging studies of adults who experienced trauma in childhood and adolescence. We are currently using 10x RNA sequencing to compare differential gene expression in CA3 of adult mice defeated when they were juveniles with that of CA3 in adult humans with a history of early trauma. By using this reverse translation approach, we hope to better understand how circuits are disrupted after early trauma, with the hope of developing more effective treatments for psychiatric disorders resulting from early trauma.

Key words:Adolescent stress, chronic stress from social defeat, early trauma

To disclose:Nothing to disclose.

Aakash Basu, Abigail Yu, Jen-Hau Yang, Samira Glaeser-Khan, Yulong Li, Alfred Kaye*

Yale University, New Haven, Connecticut, USA. UU.

Background:Post-traumatic stress disorder involves an internal state of hypervigilance to memories of past traumatic experiences. Norepinephrine (NE) has been proposed as a mediator of this process, since excessive release of NE after stress induces anxiety in animals and exacerbates PTSD symptoms in humans. Therefore, understanding the moment-to-moment processing of traumatic memories and how they alter the threat calculus in internal states requires a direct measurement of NE in the course of traumatic memory expression.

Methods:We expressed the GRAB-NE2h norepinephrine fluorescent sensor in the mouse medial prefrontal cortex (mPFC) with AAV9. We measured NE release using fiber photometry during fear conditioning while varying the delay between cues and outcomes (in groups of n = 10-13 animals). NE dynamics were measured over 20 training trials and 20 extinction trials. Reinforcement learning models were fitted for NE release induced by cues and foot shocks during the course of learning and extinction. The models included 1) time difference learning, 2) DT learning with belief states (Starkweather et al. 2017), and 3) DT learning with uncertainty state (Mikhael et al. 2022).

Results:NE is released during footshock, and NE release during predictive threat signals is increased with repeated signal/shock associations (p = 0.0026, t = 3.882, 1st forward training vs 11th training signal) . Cue-elicited EN persists in the absence of cue-shock pairs (p < 0.0001, t = 7.606, 1st advanced training vs. 1st extinction cue). Fear follow-up conditioning also increases cue-evoked NE release in 5-s follow-up conditioning (p = 0.0011, t = 4.385, 1st exercise vs. ) or 30-s follow-up conditioning (p = 0. 4501). , t = 0.7896, 1st training vs. 1st test signal), and the NE caused by the test signal decreases with increasing trace length (trace: F(2,30) = 7.136, p = 0.0029). By modeling feature conditioning using TD learning under state uncertainty, the prediction error term recap several important features of the NE release, such as:

Conclusions:Our results suggest that prefrontal norepinephrine is a more accurate threat prediction error signal than previously described. Memories of a traumatic event induce NE release that increases with the intensity of the threat memory. Reinforcement learning threat models required modifications to include constant environmental feedback and temporal uncertainty to reproduce the observed patterns of NE release. Thus, NE appears to multiplex threat and uncertainty into fear memory recall and provides a computationally intensive signal for navigating dangerous environments.

Key words:Norepinephrine, fear circuits, reinforcement learning, optical biosensors, insecurity

Divulgações: Transcend Therapeutics, Freedom Biosciences: Contract Research (self)

Arthur Godino, Marine Salery, Angelica Minier-Toribio, Vishwendra Patel, John Fullard, Eric Parise, Carole Morel, Sarah Montgomery, Scott Russo*, Panos Roussos, Robert Blitzer, Eric Nestler

Icahn School of Medicine at Mount Sinai, New York, New York, United States of America

Background:Despite growing evidence that both the ventral hippocampus (vHipp) and mesocorticolimbic dopamine systems encode fear-related information, surprisingly little is known about how dopamine signaling selectively affects vHipp representations of emotionally salient stimuli to encourage approach/approach behaviors. avoidance. To address these deficiencies, we here examine dopaminoceptive neurons in mouse vHipp, which can be separated based on their D1 or D2 dopamine receptor expression, to delineate a model of dopamine action in vHipp.

Methods:We used D1-Cre and D2-Cre mouse lines to visualize, record and manipulate D1 and D2 vHipp cells. Reporter lines were used for anatomy, snRNA sequencing, section electrophysiology, and cell type-specific in vivo calcium imaging, chemogenetics, and optogenetics. Fluorescent dopamine sensors were used to record dopamine release in vHipp.

Results:At the histological level, cells expressing D1 and D2 exhibit precise topographical organization into vHipp subfields, which we dissect further by RNA sequencing of single ordered nuclei of D1 and D2 cells. We also confirmed the pharmacological effects of dopamine on the electrophysiological properties of these cell types. Functionally, we found that anxiogenic environments and approach/avoidance conflicts elicit different patterns of calcium activity in D1 versus D2 vHipp neurons, along with dopamine release in this region. Bidirectional optogenetic and chemogenetic manipulation of the activity of vHipp D1 or D2 neurons causally demonstrated their opposing roles in mediating fear and approach/avoidance behavior. Interestingly, vHipp dopaminoceptive mechanisms also contribute to cocaine-related behaviors, suggesting drug-induced plasticity in this circuit as well.

Conclusions:Together, we propose that dopamine dynamics in vHipp act as a feedback loop bidirectionally tracking anxiety levels to drive exploratory behavior through differential recruitment of vHipp neurons D1 and D2, which in turn mediate opposing focus/focus responses. avoidance and anxiety. This work paves the way for further studies of dopamine signaling in limbic regions and underscores the complexity of the circuitry mechanisms that control affective states.

Key words:Anxiety, dopamine, in vivo imaging

To disclose:Nothing to disclose.

Camila Demaestri*, Margaux Pisciotta, Naira Altunkeser, Madalyn Critz, Dayshalis Ofray, Kevin G. Bath

Columbia University, New York, New York, United States

Background:Experiencing adversity in early life (ALS), such as B. resource scarcity, is associated with an increased risk of anxiety-related disorders. Women are twice as likely to develop anxiety-related disorders as men. A key feature of these outages is increased responsiveness to real and perceived threats. Gender-related biases in risk and symptom presentation may be related to changes in corticotropin-releasing hormone (Crh), a neuropeptide released in response to stress and important in driving the overarousal associated with threat responses. In men, ALS has been linked to changes in Crh levels in the amygdala, however the impact in women and implications for threat response remain largely unexplored.

Methods:We used the Limited Conditioning and Nesting (LBN) model of ALS in mice to assess its effects on fear-potentiated startle, a translation-relevant behavioral phenotype used to assess threat reactivity and Crh+ cell activity in the amygdala test. Mice were reared with LBN from postnatal day 4 (PD4) to PD11 and tested in the fear-potentiated startle task as adults ~PD70. Startle levels were measured during moderate and high anticipation states, in which mice were given the 50 ms startling white noise randomly (moderate anticipation) or with a previous tone previously associated with a foot tap (high anticipation). The activity of Crh+ neurons in the central amygdala was measured using two methods. First, the number of active Crh+ neurons was quantified after the test using cFos as a neuronal activity marker. In a separate cohort of mice, the Ca2+ of Crh+ neurons was measured in vivo during fear-potentiated startle using fiber photometry. Two-way ANOVAs were used to test the main effects of reproduction (control x LBN), sex (male x female), and an interaction in the startle response to the percentage of random and elicited white noise (n = 15-17/cluster). of Crh+ neurons co-expressing cFos (n=6-7/group), and in z-score fiber photometry and AUC calculations (n=5-7/group).

Results:We found that LBN improved acoustic startle when the startle white noise was preceded by a conditioned tone (response: F(1.57) = 7.37, p = 0.008, partial eta2 = 0.11) and when it was presented randomly ( reaction: F(1.57 ). ) = 9.61, p = 0.003, partial eta2 = 0.14), which indicates greater reactivity to threats in states of high and moderate expectation. This effect was most strongly observed in LBN females, who show a greater change in startle compared to control females. Female LBN mice also increased cFos+ and Crh+ co-labeling in the central amygdala (interaction: F(1,23)=4.29, p=0.04), partial eta2=0.15) and sustained Ca2+- activity of Crh+ neurons during conditioned tone (interaction: F(1,23)=4.63, p=0.04), eta2partial=0.16), suggesting a role for central amygdala Crh+ neurons in the anticipation of threats.

Conclusions:Current work identifies a possible gender-specific mechanism to improve response to threats as a result of ALS. Ongoing studies will lay the groundwork for understanding gender differences in pathology and help to improve individualized treatments and interventions based on the individual's past experience and gender.

Key words:Adversity in early life, startle aggravated by fear, corticotropin-releasing hormone, sex differences

To disclose:Nothing to disclose.

Marcus Weera*, Jason Middleton, Nicholas Gilpin

LSU Health New Orleans, New Orleans, Louisiana, USA

Background:In humans, stressful events can induce avoidant coping (ie, sustained avoidance of stress-associated stimuli) in some individuals, which is associated with adverse outcomes such as increased alcohol consumption and increased anxiety. Using rats, our laboratory has shown that stress caused by predator odors (ie lynx urine) elicits sustained avoidance of a stressful context in a subset of individuals termed "avoiders". Interestingly, avoidant rats show a sustained increase in alcohol self-administration (AS) after stress exposure, a phenomenon absent in non-avoidant rats exposed to stress and recapitulative findings in humans. Our published work shows that CRF1 receptor antagonism in the central amygdala (CeA) rescues stress-induced SA alcohol escalation and attenuates avoidance of a stress-matched context in avoidant rats. Furthermore, we show that avoidance of a context corresponding to stress is mediated by CeA neurons that project to the lateral hypothalamus (LH), a brain region known to modulate motivated behavior. The main objective of this study is to test the hypothesis that the stress-induced increase in SA alcohol and avoidance behavior is supported by the activation of CeA-LH neurons that express the CRF1 receptor.

Methods:All experiments were performed on male and female CRF1-Cre-tdTomato mice bred in our laboratory. In Experiment 1, we used a combination of retrograde scanning and c-Fos immunohistochemistry to test the hypothesis that stress produces more c-Fos+ CRF1 CeA-LH neurons in avoiders compared to non-avoidants (N = 11-14 mice/ group). In Experiment 2, we used ex vivo cutting electrophysiology to characterize synaptic transmission and intrinsic properties of CRF1+CeA-LH neurons in stressed and non-avoidance avoiders and non-stressed controls (N = 38-42 cells/cluster) . In Experiment 3, we used chemogenetics to test the hypothesis that in vivo inhibition of CRF1-CeA-LH neurons rescues stress-induced alcohol SA escalation, context avoidance paired with stress, and alcohol-like behavior. anxiety measured with the elevated plus maze (N=7-11 rats/group). To inform future hypotheses, in Experiment 4 we used a Cre-dependent virus-mediated anterograde scanning approach to identify additional brain areas receiving projections from CRF1+CeA neurons (N = 4 mice). Data were analyzed using multivariate ANOVA and Tukey's post hoc tests where appropriate.

Results:In Experiment 1, stress increased the number of c-Fos+ CRF1 CeA-LH neurons in avoidant rats (p < 0.01). In Experiment 2, we found that stress attenuates sIPSC frequencies in CRF1-CeA-LH neurons (p < 0.05), which may contribute to increased excitability of these neurons. In Experiment 3, chemogenetic inhibition of CRF1-CeA-LH neurons rescued the stress-induced increase in alcohol SA (p < 0.05), anxiety-like behavior, but not alcohol-associated context avoidance. In Experiment 4, Cre-mediated anterograde tracing showed that CRF1-CeA neurons project to a variety of brain areas (in addition to the LH), including the nucleus accumbens, insula, lateral septum, bed nucleus of stria terminalis, pre- optica and ventromedial hypothalamus. , medial amygdala, lateral habenula, paraventricular thalamic nucleus, zona inserta, piriform cortex, and periaqueductal gray matter. No gender differences were found in any of the experiments.

Conclusions:These results suggest that increased excitability of CeA-LH neurons expressing CRF1 supports increased alcohol consumption and anxiety-like behaviors in avoidant rats following stress exposure. Current work is focused on elucidating the extended neurocircuitry that contributes to this phenomenon. Future work focused on identifying the molecular mechanisms that modulate the activity of CRF1-CeA-LH neurons and related neurocircuitry may discover new targets for the treatment of alcohol abuse and stress-related anxiety.

Key words:Anxiety and stress, alcohol, central amygdala

To disclose:Roche In Vitro Diagnostics: Consultant (spouse)

Ka Ng, Michael Pollock, Abraham Escobedo, Brent Bachman, Susan Sangha*

Indiana University, Indianapolis, Indiana, USA

Background:Stressful events can have powerful and lasting effects on behavior, particularly by disrupting normal fear regulation and reward processing. Post-traumatic stress disorder (PTSD) has become a growing public health problem, with a lifetime prevalence of approximately 6.4% of the US population. Growing evidence suggests that PTSD can impair the ability to discriminate between different stimuli, particularly when PTSD disrupts the ability to use safety cues and overgeneralizes the effects of fear cues.

Our lab uses a unique rodent behavioral task that allows us to study stimulus discrimination along with fear regulation and reward processing behavior. Male Long Evans rats show significant differentiation between signals representing reward, fear and security. Specifically, they spent more time seeking rewards during a sucrose prediction reward cue than during a fear or safety cue, and they spent more time freezing during a foot tapping prediction fear cue compared to a fear cue. security or reward. Crucially, they also show suppressed freeze values ​​when the fear signal is presented simultaneously with the safety signal, but without foot shock (fear + safety signal). Prior exposure to stress reduces this anxiety-suppressing effect.

Our previous work has shown that areas of the prefrontal cortex and the amygdala contribute to this learning. However, the precise connections between these subregions in the ability to express learned security remain to be tested.

Methods:Adult male Long Evans rats (n = 25-30) were used in the present study because we have previously shown that female rats do not learn to suppress fear in the presence of a safety signal. Using a dual viral approach, we expressed mCherry-tagged hM4D(Gi) receptors in the infralimbic (IL) cortex expressing neurons projecting to the basolateral amygdala (BLA) or central amygdala (CeA) to neurons induced by CNO (3 mg/kg). , i.p.) neuronal inhibition. All rats underwent stimulus discrimination training combining a reward cue with sucrose, a fear cue with paw shock, a safety cue without sucrose and without paw shock, and a composite fear+safety cue without shock. in the legs. All rats received vehicle i.p. Injections during the first 3 discrimination sessions. Then, using an within-subject design, rats received either vehicle or CNO during discrimination sessions 4 and 5. Freezing and reward-seeking behaviors were quantified for each cue and collapsed during discrimination sessions 4 and 5, followed by 2-way repeated measures ANOVA comparing drug and signal.

Results:We show that the infralimbic projection to the central amygdala is necessary to suppress freezing in the presence of the safety signal, whereas the projection to the basolateral amygdala is not. Specifically, only CNO inhibition of IL-CeA neurons resulted in a failure to suppress freezing during fear and security signals compared to the fear signal (p > 0.05). In contrast, freezing was significantly lower than the fear signal in the same mice (n = 5) under vehicle conditions (p < 0.05) and in mice (n = 6) with unconfirmed mCherry expression in what was injected with CNO (p < 0.01) or vehicle (p < 0.05).

Conclusions:The loss of regulation of discriminatory anxiety observed specifically during IL-CeA inhibition is similar to the disturbance seen in individuals with PTSD who are unable to regulate anxiety in the presence of a safety signal.

Key words:Safety learning, fear regulation, amygdala, medial prefrontal cortex

To disclose:Nothing to disclose.

Austin Coley*, Jeremy Delahanty, Assaf Ramot, Rachelle Pamintuan, Lexe Linderhof, Vivian Liu, Caroline Jia, Harini Advikoluna, Sama Shathaya, Kanha Batra, Deryn LeDuke, Felix Taschbach, Romy Wichmann, Hao Li, Kyle Fischer, Marcus Benna, Takaki Komiyama, Kay Tye

Das Salk Institute for Biological Studies, La Jolla, California, USA.

Background:A critical problem in the field of mental health is the lack of granularity in diagnostic practices. For example, a patient who sleeps and eats too much might be prescribed the same antidepressant as a patient who sleeps and eats too little. This could explain the low efficacy rates of first-line antidepressants and requires further analysis beyond the DSM. Anhedonia, described as the inability to experience pleasure, is a central feature that is expressed in both major depressive disorder and schizophrenia. Anhedonia is associated with dysregulation in the brain's reward pathways, which include the medial prefrontal cortex (mPFC), which is highly involved in processing emotions and valences, which are essential for encoding hedonic values. Dopamine (DA) transmission strongly regulates mPFC cortical activity and associated behavior and is implicated in anhedonia. However, it is still unknown how DA modulates the activity of the mPFC valence-specific neuronal population during stress-induced anhedonia.

Methods:We implemented learned helplessness (LH) and mild chronic stress (CMS) protocols to induce anhedonia in mice. We projected an anhedonic phenotype score for individual mice. To investigate the effects of DA modulation on valence-specific neuronal populations of mPFCs during anhedonia, we performed longitudinal 2-photon calcium imaging in vivo using optogenetic techniques to detect DA inputs into the ventral tegmental area (VTA) in the mPFC and simultaneously measure the activity and dynamics of the mPFC population during a Pavlovian conditioning task in mice exposed to LH and CMS. Both males and females were used in this study.

Results:Our preliminary results showed a significant reduction in reward consumption and sociability in LH mice (Pearson correlation, r = -0.69, p = 0.03), but not in CMS mice (Pearson correlation, r = -0, 16, p = 0.58), indicating a difference in behavioral phenotypes depending on stress. After initial exposure to CMS, we observed a significant decrease in mPFC activity during aversive studies in susceptible mice compared to robust and control groups (one-way ANOVA (F(2,398) = 13.66, p<0.001; Tukey post hoc -Kramer), susceptible mice showed a significant increase in activity during reward trials compared to resilient groups (one-way ANOVA (F(2,398) =7.26, p=0.0008 Tukey-Kramer post hoc susceptible /resistant, p=0.002, susceptible/control, p=0.999 , resilient/control, p=0.003), but no change in control mice.

Conclusions:These results indicate that anhedonic states affect the valence encoding properties of mPFCs and that acute and severe stressors can lead to different etiologies of mild chronic stress. Overall, these experiments point to the need for greater granularity in the measurement of neural behavior and activity, as these factors may decipher the inducing conditions of stress-induced anhedonia, as well as the underlying biological pathology, leading us to future medicine. individualized.

Key words:Valency, anxiety and depression, medial prefrontal cortex

To disclose:Nothing to disclose.

Robert Rozeske*, Leonie Runtz, Aaron Sossin, Alexandra Keinath, Mark Brandon

University of Toronto, Scarborough, Toronto, Canada

Background:Assessing a situation as threatening or safe is critical to our survival. However, this process can be affected in people with post-traumatic stress disorder (PTSD). Consequently, neutral environments are indistinguishable from a traumatic memory and result in the reliving of psychological distress from the original trauma. One theory for the pathophysiology of PTSD is impaired context processing. Previous work indicates that contexts in the hippocampus (HPC) are represented by sets of "place cells" that collectively create a spatial map. Although the HPC is essential for episodic memory, the dynamics of the spatial representation of the HPC during aversive memory formation and neutral or threatening memory retrieval is not fully understood.

Methods:To investigate contextual fear discrimination, we used one-photon calcium microendoscopic imaging in free-behaving male C57BL/J6 mice (n = 8-11) during a novel contextual memory retrieval task. Mice were surgically injected with AAV to express the calcium reporter GCaMP6f in HPC CA1 CaMKII+ cells; A GRIN lens was subsequently implanted for imaging. An adapted fear conditioning device, composed of speakers and a cylindrical LED screen (90 cm in diameter), presented two different contexts, A and B, while the mice remained in the same physical space. On days 1 and 2, mice were placed in neutral context B in the morning and fear conditioned with paw shock in context A in the afternoon. On day 3, mice were placed in the device for 12 min and presentations of contexts A and B alternated repeatedly at 2 min intervals. HPC activity and freezing behavior were recorded during the task. To investigate spatial coding, peak probabilities were calculated from neuronal calcium transients and spatial cell rate maps were constructed. For each mouse, neuronal activity was correlated with a population vector of mouse locus cell pool activity. This population vector correlation was used to assess the strength of the HPC spatial map at a given point in time. A separate group of unconditioned control mice (n = 4) underwent similar CA1 and behavior recording procedures. Data analysis was performed with Matlab and statistical significance was calculated using goodness tests, nonparametric tests, Pearson's correlation, and between-subject comparisons with mixed controls.

Results:We report three main findings in our fear conditioning task: (1) On day 1, fear conditioned mice significantly increased freezing (p < 0.01 Friedman) and differed from unconditioned controls (p < 0.01 Kruskal-Wallis ). Conditioned and unconditioned mice showed significantly different freezing on day 2 of conditioning (p < 0.01 Kruskal-Wallis). On day 1, the HPC spatial map was significantly remapped in fear-conditioned context A compared to neutral context B (p < 0.01 Kolmogorov-Smirnov; p < 0.05 Wilcoxon sign rank for context A ). (2) During the "teleport" contextual freezing behavior on day 3, behavior changed significantly during the trial (p<0.01 Friedman) and was different between conditioned and control mice (p<0.01 Kruskal-Wallis ). HPC spatial maps of contexts A and B were significantly altered during context transitions (p < 0.05 Wilcoxon sign rank for conditioned mice). (3) During the time around the context transitions, stronger A spatial context maps were correlated with stronger freezing and stronger B context maps were associated with less freezing (Pearson correlation p < 0.05).

Conclusions:These results reveal the temporal relationship between the HPC spatial map and memory formation/retrieval processes. Despite an unaltered context, the formation of an aversive memory destabilized and altered the spatial map. Furthermore, context switching in "teleportation" studies has illustrated the dynamic relationship between spatial map strength and fear memory expression. These studies connect the field of spatial navigation with emotional behavior and introduce a task to identify safe and dangerous contextual representation circuits that can guide the development of specific therapies for PTSD.

Key words:Contextual Anxiety, Generalized Anxiety, Hippocampus, PTSD, Spatial Memory

To disclose:Nothing to disclose.

Takashi Kitamura*, Joseph Terranova, Sachie Ogawa

University of Texas Southwestern Medical Center, Dallas, Texas, USA

Background:The formation and maintenance of long-term memory of episodes is important in daily life. One feature of episodic memory is autobiographical; requires first-hand experience, accompanied by acting out yourself in an episode, and retains the first-person point of view that distinguishes your episode from others. Although it is speculated that the self-reference effect is closely related to the process of transformation from episodic to semantic memory in humans, the neural circuitry mechanisms for the time-limited self-reference effect on memory retrieval remain unknown.

Methods:To directly examine the effect of self-reference on fear memory retrieval in mice, we established an observational contextual fear conditioning (OCFC) paradigm and analyzed neural circuitry mechanisms for both recent (1-day) and distant (1-day) memory recall. 28 days) to observe The CFC examines the observer side and the demonstrator side. Because the observer mice showed the freezing behavior on the observer side but not on the demonstrator side at the last time point, while the observer showed the freezing behavior on both at a distant time point. It is important to note that the demonstrator's increased freeze response is not due to fear generalization. This behavioral model is suitable for assessing the temporal effect of self-reference on recall from observational fears. 10-15 week old C57BL6J mice were used in the observer and demonstrator. The experimenters were blind to the genotype of the mice and the experimental designs were balanced. An equal number of animals were assigned to each experimental group (ie, genotype, sex, age). Sample size determination: Using data from our previous reports (Terranova et al., 2022, Neuron), we performed a performance analysis with an effect size of 0.9 and an alpha value of 0.05, corresponding to a sample size group of 10 mice revealed. Based on our previous studies (Kitamura et al., 2017, Science, Terranova et al., 2022, Neuron), we assigned 6 mice per group for histology. Statistical analysis: Comparisons between two groups were analyzed using unpaired t-test or paired t-test if normally distributed, otherwise Wilcoxon rank sum or signed rank test. Multi-group comparisons were assessed using one-way, two-way, or repeated measures analysis of variance (ANOVA), followed by post hoc tests when significant main effects were identified. The null hypothesis was rejected at the P < 0.05 level.

Results:We found that dorsal hippocampus activity is crucial for recent memory retrieval of CFC observed from the observer side (U = 13, P = 0.004, Mann-Whitney U test), whereas medial prefrontal cortical (mPFC) activity for long-distance memory is essential CFC memory observed on both the observer and demonstrator sides (t19 = 2.42, P = 0.03, unpaired t-test). Consequently, recent CFC recall observed on the observer side increased Arc expression in dCA1 (t8 = 2.69, P = 0.03, unpaired t-test). but not mPFC (t8 = 0.74, P = 0.48, unpaired t-test), while CFC observer long-distance memory recall affected bow expression in mPFC in both observers (t8 = 3, 13 , P = 0.01, unpaired t-test) and the increased demonstrator side (t10 = 3.32, P = 0.01, unpaired t-test), but not dCA1. Optogenetic terminal inhibition further demonstrated that the mPFC-BLA pathway is critical for long-distance memory retrieval of the observed CFCs.

Conclusions:Observational CFC memory is maintained permanently. Whereas observed CFC requires the dorsal HPC (dHPC) at a recent time point, observed CFC requires the mPFC-basolateral amygdala (BLA) pathway at a distant time point. Furthermore, we demonstrate that recent observation CFC memory can only be retrieved egocentrically, whereas remote observation CFC memory can be retrieved both as egocentric and allocentric retrieval, depending on the animal context. Finally, we show that mPFC neural activity during CFC observation is required for successful retrieval of both egocentric and allocentric observational CFC memory at a distant time point.

Key words:Dorsal hippocampus, medial prefrontal cortex, observational learning, fear conditioning, mouse models

To disclose:Nothing to disclose.

Tanner Francis*, Andrew Belilos, Christie Sanders, Ayesha Sengupta, Geoffrey Schoenbaum

University of South Carolina, Columbia, South Carolina, USA. UU.

Background:Surviving harmful environmental stimuli requires encoding an appropriate response to future threats. The nucleus accumbens (NAc) is a center for processing motivational information, including aversive events, and dictates the response to these salient events. Highly prominent aversive events promote phasic changes in striatal cholinergic interneuron (ChI) firing, which may contribute to learning. Furthermore, substance P is known to increase ChI activity over a period of seconds to minutes, an increase observed after a pause in activity in response to aversive stimuli. Downstream signaling via increased ChI activity via substance P activation promotes plasticity in the NAc milieu spiny neurons (MSNs) via muscarinic-1 receptors, which may provide a synaptic substrate for learning about these aversive events prominent. Therefore, we wanted to test the hypothesis that increased acetylcholine release by substance P predicts and supports associative learning of salient aversive events.

Methods:A Pavlovian fear conditioning paradigm was used to study aversive learning in mice, using freezing in response to associative cue as the main measure of learning. To determine the dynamics of selective acetylcholine release, mice were injected with an adeno-associated virus expressing the genetically encoded acetylcholine sensor GRAB-ACh3.0 in the NAc core and in vivo signals recorded by fiber photometry. in wild-type C57BL/6J. -Rats measured during different stages of fear and memory conditioning. All GRAB-ACh signals were normalized by z-score and changes quantified using the area under the curve. To determine acetylcholine responses to salient environmental cues, mice received footshocks of varying intensities (0.1–1.0 mA) at random intervals. To further test the role of acetylcholine in enhancement, a subset of mice were subjected to latent inhibition procedures to reduce the enhancement of aversive signals. To assess the role of substance P in mediating acetylcholine signaling and aversive learning, mice were injected with L-733060, an antagonist of substance P's major receptor, the neurokinin-1 receptor (NK1R). Furthermore, ChI-Cre transgenic mice were injected with an NK1R guide RNA in the presence of Cas9 for a ChI selective NK1R conditional knockout. Finally, to determine the need for acetylcholine signaling in stimulus-dependent learning, mouse NAc was directly infused with pirenzepine, a muscarinic-1 receptor-like antagonist, through a cannula implanted into the NAc.

Results:Stimulus-dependent fear conditioning produced a multiphasic response, including activity in response to a new cue, a decrease in release after a foot tap (pause), and a sustained increase in activity (1-2 seconds) after the break. Shock alone produced an identical pause followed by an increase in release, as seen during conditioning, indicating that salient stimuli in the absence of cues evoke these phasic changes in acetylcholine. Increasing shock intensity caused an increase in acetylcholine release (F(3,28) = 3.420, p<0.05) and the response decreased during subsequent exposures to stimuli (F(1,28) = 6.793, p <0.05), suggesting that these increases in acetylcholine release signals highlighting the NK1R antagonist treatment blocked the increase in activity by 0.6 mA (t(9) = 2.017, p<0.05), suggesting that the Substance P signaling is responsible for encoding the stress of the aversive stimulus. Cue recall was improved by NK1R treatment (t(40) = 3.801, p<0.001), NK1R CRISPR knockdown (t(26)=3.332, p<0.01) and latent inhibition (t(10) = 2.170 , p<) decreased significantly by 0.05). In all treatment cases, motor responses did not explain the change on freezing. Furthermore, latent inhibition (t(10) = 3.886, p<0.01) and NK1R antagonist treatment (t(13) = 2.140, p<0.05) suppressed cholinergic rebound activity without affecting the pause during cue retrieval. Finally, pirenzepine decreased the call sign when administered directly into the NAc before conditioning (t(17) = 3.253, p < 0.01), but not before the call sign (t(11) = 1.220, p > 0 .05).

Conclusions:These results provide evidence of a central NAc microcirculation that requires substance P and acetylcholine release for the plasticity underlying stimulus-dependent aversive learning. Furthermore, this work involves substance P signaling and not necessarily the intrinsic mechanisms in ChI rebound during aversive events and cue learning, which signals salient environmental features. This work reveals a mechanism for a peptide-acetylcholine microcircuit that shapes the response to aversive events by dictating stimulus emphasis. These findings may have broader implications for processing stressful events that trigger anxiety and depression.

Key words:Prominence, acetylcholine, neuropeptides, aversive learning, ventral striatum

To disclose:Nothing to disclose.

Frances Xia*, Nina Vishwakarma, Valeria Fascianelli, Frances Ghinger, Stefano Fusi, Mazen Kheirbek

University of California - San Francisco, San Francisco, California, USA. UU.

Background:Major depression is characterized by functional changes at the network level, with the amygdala (AMY)-ventral hippocampus (vHPC) pathway and associated regions being key components. However, it remains unclear how changes in emotional state are reflected in the activity patterns of individual neurons and populations in the AMY-vHPC network.

Methods:Here, we used high-density neuropixel probes to record single-unit activity across the entire AMY-vHPC network, including the AMY and vHPC subregions, as well as the medial prefrontal cortex (mPFC) and thalamus. This allowed us to study how stress modulates the representation of emotional information in the AMY-vHPC circuit and the impact on reward seeking behavior. Mice (male and female, total n = 60) were first exposed to the chronic stress of social defeat, a well-validated rodent paradigm that classifies stressed mice as those exhibiting depression-like behavior (prone) and those who are not (resistant). 🇧🇷 After defeat, we recorded single-unit activity via a thalamic AMY-vHPC-mPFC network while mice performed a head-fixed sucrose preference test, in which they were free to choose between water consumption and food rewards. sucrose, a classic test for anhedonic behavior. Statistical significance was assessed using a two-way ANOVA followed by post-hoc tests where appropriate. When data were significantly non-normal or variances were significantly unequal, nonparametric tests were used, including the Kruskal-Wallis, Mann-Whitney, and Wilcoxon signed rank tests.

Results:Our results show that sucrose preference after defeat was correlated with social interaction ratio (P = 0.0002), a standard measure of susceptibility to stress. At the level of individual neurons, we found that peak activity increased greatly during reward consumption in control (unstressed) mice via the thalamic AMY-vHPC-mPFC network, but stressed mice showed region-specific changes in neuron patterns. firing, including decreased activity in AMY and vHPC neurons (P < 0.0001) and increased firing rates in mPFC neurons (P < 0.0001). Interestingly, neurons in AMY and vHPC showed greater reward selectivity in stressed mice, despite a lower preference for sucrose in behavior. To further investigate this phenomenon at the population level, we use support vector machine classifiers to decode reward representations. We found that in stressed mice, future reward choice (sucrose or water) could be decoded seconds before choice in AMY, mPFC, and vHPC neurons (P < 0.0001), indicating a rigidity in future reward displays. Furthermore, neurons in these regions in susceptible mice showed less change in decoding fidelity before and after reward (P<0.0001), indicating lower reward sensitivity compared to controls and resistant mice. Next, we examine how stress alters the interaction between brain regions. We found that coordinated activity between AMY and vHPC neurons correlated with individual animal preference for sucrose (P  = 0.003), suggesting that a reduced AMY-vHPC interaction may underlie the anhedonia. Consistently, chemogenetic activation of the AMY-vHPC pathway rescued anhedonic behavior in susceptible mice (P = 0.01).

Conclusions:Together, our results indicate that chronic stress alters individual neuron firing patterns and population reward representations in the AMY-vHPC network, and these changes may be responsible for driving post-stress anhedonic behavior.

Key words:Mood disorders, chronic stress from social defeat, neural circuitry and animal behavior, neural decoding, reward representation

To disclose:Nothing to disclose.

Mark Gergues*, Joshua Bratsch-Prince, Shazreh Hassan, Mona Li, Arsine Kolanjian, Victoria Turner, Mazen Kheirbek

University of California, San Francisco, San Francisco, California, USA. UU.

Background:Recent work has uncovered the hippocampus (HPC), which has been classically associated with learning, for its role in encoding emotionally charged environments and generating appropriate behavioral responses. Specifically, new findings from our lab have identified ventral pole HPC neurons that project to the hypothalamus, encode anxiogenic environments, and bidirectionally modulate avoidance behavior. However, it is still unknown how and which inputs are involved in the generation of fear-related representations in the ventral HPC. Using a whole-brain cell-type-specific anatomical screen, we identified the anterior portion of the paraventricular nucleus of the thalamus (PVT), an area involved in processing salient emotional stimuli, as a putative source of anxiety-related information for HPC. In this study, we analyzed the anatomical organization of the PVT-vHPC circuit and its contribution to anxiety-related behavior.

Methods:We used a Cre-dependent strategy to label paraventricular thalamic cells (PVTs) with vHPC projection with the DREADD receptor inhibitor hM4Di. We injected retroAAV-Cre into vHPC and a Cre-dependent chemogenic inhibitor, hM4Di, into PVT, both bilaterally. Four weeks later, we injected the animals with NOC (3 mg/kg) 15 min before performing the elevated plus maze field test. To assess collateral projections of cells projecting vHPC in PVT, we used anatomical markers (a Cre-dependent expression of synaptophysin-mRuby in PVT and retroAAV-Cre in vHPC) and viral barcode approaches. Four weeks later, the animals were sacrificed, the brains removed, followed by whole-brain histology to identify axon fibers in other brain regions. Next, we try to identify how the PVT input differs from other inputs in the vHPC during behavior using dual-fiber photometry. We injected a retrograde jGcAMP8m into the vHPC and then implanted fiber optics into the PVT and basal-lateral amygdala (BLA) to record BLA-vHPC and PVT-vHPC neurons simultaneously. Four weeks later, we recorded calcium signals in PVT and BLA while the animals explored the elevated plus maze and the open field.

Results:Inhibition of the PVT-vHPC signaling pathway resulted in reduced time in the open and intermediate area of ​​the elevated plus maze (p < 0.05) and reduced time in the center of the open field (p < 0.05). In our experiment with synaptophysin, we identified axon fibers in the nucleus accumbens, in the central amygdala, in the bed nucleus of the stria terminalis and in the zona incerta. Dual fiber photometric recordings revealed differential responses of BLA-vHPC versus aPVT-vHPC in the elevated plus maze and free field test, indicating that these two areas convey different information to vCA1 during exploration of anxiogenic environments.

Conclusions:Here we identify a role for PVT-vHPC projections in modulating anxiety-related behavior. These PVT-vHPC projections collateralize the amygdala and nucleus accumbens, suggesting that transmission from PVT-vHPC neurons may play an important role in orchestrating behavioral responses to threatening stimuli. Responses in PVT vHPC neurons to the anxiogenic compartments of the elevated plus maze differed from those in the BLA vHPC, which showed consistent increases in activity when animals explored anxiogenic areas. This indicates a different and specialized processing of anxiogenic information by PVT-vHPC neurons compared to the well-studied BLA-vHPC signaling pathway.

Key words:Ventral hippocampus, paraventricular nucleus of the thalamus, fear circuit

To disclose:Nothing to disclose.

Munir Kutlu*, Jennifer Tat, Jennifer Zachry, Erin Calipari

Vanderbilt University School of Medicine, Nashville, Tennessee, EUA

Background:The execution of adaptive behavior depends on the ability of organisms to foresee potential threats in their environment. For this, animals learn to predict when aversive stimuli will occur and learn what actions are necessary to avoid contexts and situations with potentially negative results. Equally important, however, is the ability to learn when aversive stimuli are unlikely to occur. This balance allows animals to avoid potential negative consequences while exploring their environment when it is safe and unlikely to cause harm. Release of dopamine from the nucleus accumbens (NAc) has been causally linked to adaptive aversive learning, and its dysregulation is a central phenotypic feature of anxiety and stress disorders. Therefore, understanding the role of dopamine in aversive learning is important both for understanding neuromodulatory signaling in the brain and for the importance of its dysregulation in psychiatric disease states.

Methods:We used an aversive conditioned inhibition design combined with fiber photometry and optogenetics to test the role of NAc-dopamine in aversive learning. In this task, a target cue was presented alone (to predict the occurrence of an electric foot shock) or in combination with a secondary cue (to predict that the electric foot shock would be omitted in the present study). Using a fluorescent dopamine sensor (dLight1.1), we recorded the dopamine response to signals that predict the presence and absence of aversive electric shocks. Next, we optogenously manipulated dopamine responses during lost-paw shocks to demonstrate a causal relationship between NAc-dopamine and inhibitory conditioned learning. Finally, we use a theory-based computational model of associative learning (Kutlu-Calipari-Schmajuk, KCS model) to explain our results and derive new predictions about the role of dopamine in aversive learning.

Results:Using optical approaches to directly record and manipulate dopamine release from the NAc in conscious and well-behaved animals, we show that dopamine responses evoked at the time of omission of aversive outcomes are responsible for the expression of conditioned responses. The magnitude of the dopamine response at a lost foot shock scales positively with the prediction of aversive outcome in this study; However, this effect was only apparent at the time of the omitted result, not in response to the predictive cue itself. Importantly, by optogenetic manipulation of this signal, we have shown that dopamine does not transmit an error-based signal in this context, since amplification of this signal is disrupted rather than reinforcing learning. Finally, using the DED model, we show that these effects can be explained by dopamine signaling the perceived importance of predicted aversive events, but not the prediction error.

Conclusions:Together, we show that NAc nucleus dopamine responses to expected but omitted aversive stimuli causally determine associative learning to aversive stimuli in mice. These results add to the growing literature supporting dopaminergic encoding of perceived dopamine stress in the NAc. Our findings about the encoding of dopaminergic information in associative learning also have important clinical implications for anxiety and stress disorders. Taken together, these findings have far-reaching implications for learning and memory theory, understanding the mesolimbic neurocircuitry, and the psychopathology of anxiety and stress disorders.

Key words:Dopamine, safety learning, aversive learning

To disclose:Nothing to disclose.

Mikaela Laine, Julia Mitchell, Johanna Rhyner, Leena Ziane, Emmett Bergeron, Rose Clark, Akshara Kannan, Jack Keith, MaryClare Pikus, Rebecca Shansky*

Northeastern University, Boston, Massachusetts, EUA

Background:Pavlovian fear conditioning is a widely used paradigm for studying the neural mechanisms that mediate aversive learning. However, the behavioral outcome metric has historically been the only "freezing" response, despite the complex nature of the task and the multidimensional fear responses that animals can exhibit. Especially in the context of greater consideration of gender as a biological variable, expanding the repertoire of our behavioral observations in this classic task will be decisive for a more differentiated understanding of learning and memory processes.

Methods:Male (n=100) and female Sprague-Dawley rats (n=100) underwent auditory fear conditioning in standard chambers with 1.0 mA, 0.5 mA, 0.3 mA, or no unconditioned stimulus. Some animals also underwent learning and absorption recovery procedures on consecutive days. Movement behavior was recorded with overhead cameras and followed with Ethovision software. Vocalizations were recorded and analyzed using DeepSqueak software. Some animals were sacrificed 90 minutes after the end of fear conditioning, and areas of the prefrontal cortex, periaqueductal gray matter (PAG) and spinal cord were immunostained for c-fos expression.

Results:We observed significant main effects of gender and shock intensity on the number of alarm calls elicited during fear conditioning. Men made significantly more alarm calls than women, and these calls also lasted longer during the training session in men than in women. Propensity to make alarm calls tracked shock intensity and corresponded with freezing behavior in men but not in women. Alarm calls emerged later when CS-US presentations were not explicitly paired than when they were paired, suggesting that alarm calls may reflect associative learning. However, alarm calls can be observed both during ITIs and during the CS presentation. We also observed gender differences in correlations between c-fos activity and conditioned and unconditioned responses.

Conclusions:This work provides new evidence that men and women process a Pavlovian fear conditioning session differently, both on multiple behavioral dimensions and on the activity of key brain regions. Our data have important implications both for basic scientists who use Pavlovian fear conditioning to study learning and memory processes and for translational neuroscience who hopes to use rodent models to understand aversive learning disorders such as PTSD.

Key words:Fear conditioning, gender differences, ultrasonic vocalization, periaqueductal gray (PAG), prefrontal cortex

To disclose:Nothing to disclose.

Claire Stelly, Alyssa Hall, Kasey Anderson, Anh Duong, Naseem Azadi, Jeffrey Tasker, Jonathan Fadok*

Tulane University, New Orleans, Louisiana, USA

Background:Persistent symptoms of hyperarousal, including exaggerated startle responses and increased sympathetic tone, are hallmarks of PTSD. We hypothesize that interoception of sympathetic activity directly regulates threat responses to promote and maintain hyperarousal. Noradrenergic neurons in the nucleus tractus solitarius (NTS) receive ascending inputs from major organ systems and send noradrenergic/glutamatergic projections to the central amygdala (CeA), a key region for orchestrating threat responses. We propose that traumatic experiences alter NTS activity to promote exaggerated threat responses.

Methods:Hyperarousal symptoms were induced using the Traumatic Experience with Stress Reminders (TERS) paradigm, which consisted of a single exposure to a traumatic foot impact (10 s, 2 mA), followed by six short, intermittent exposures to a contextual reminder. experience of more than 24, last days. Male and female C57Bl6/J mice were randomly assigned to control (n = 8) or TERS (n = 22) groups. Acoustic startle responses, resting heart rate, and sociability were measured before and after the trauma paradigm.

The activity of the NTS noradrenergic neuron population was analyzed by injecting AAV5-CAG-FLEX-GCaMP6f into the NTS of TH-Cre mice (n=2) and implanting an optical fiber for photometry.

Chemogenetic activation of noradrenergic input from the NTS to CeA was assessed by injecting AAV5-hSyn-DIO-hM3dGq into the NTS of TH-Cre mice (n = 2) and local application of the DREADD agonist deschloroclozapine/vehicle via bilateral cannulas into the achieved CeA.

Results:Mice subjected to the TERS paradigm had increased acoustic startle (p = 0.006, Welch's t-test) and increased heart rate (p = 0.009, Mann-Whitney test) compared to controls without shock. Based on the acoustic startle response, the trauma-exposed group can be divided into a vulnerable group with significantly greater startle responses and a resistant group with startle responses as a control. Sociability did not differ between groups (social interaction events p = 0.56; time of social interaction p = 0.86, Welch's t test). No gender difference was observed at all.

Preliminary data from fiber photometry suggest that surprise and aversive stimuli elicit calcium responses in noradrenergic neurons of the NTS. Furthermore, chemogenic activation of NTS noradrenergic axon terminals in CeA potentiated the acoustic startle response in naïve mice (p = 0.05, paired t-test).

Conclusions:Traumatic experiences along with situational memories trigger symptoms of hyperarousal in both male and female mice. Noradrenergic neurons within the NTS likely fire during salient or aversive stimuli, and activation of noradrenergic projections from the NTS to CeA potentiates startle. These results suggest that the NTS may regulate threat responses through its projections to the central amygdala.

Key words:Hyperarousal, central nucleus of the amygdala, noradrenergic system, nucleus tractus solitariusiii

To disclose:Nothing to disclose.

Emily Newman*, Erin Hisey, Hector Bermudez, Nicholas Ressler-Craig, Kerry Ressler

McLean Hospital da Harvard Medical School, Somerville, Massachusetts, EE. UU.

Background:Stress-induced psychopathologies, such as post-traumatic stress disorder, can severely impair emotion regulation and heighten responsiveness; in some patients, this manifests itself as increased aggression. The central amygdala (CeA) is a crossroads of neural circuits that modulate both threat and aggression responses. In our current work, we use mouse models of naturalistic agonist behavior to study the neural basis of offensive (ie, territorial) attacks and self-defense. We used single-cell calcium imaging and chemogenetics to assess CeA neurons that express the well-characterized stress-signaling corticotropin-releasing hormone (Crh) neuropeptide.

Methods:Male CRH-ires-Cre mice were given intra-CeA-AAV5-EF1a-DIO-GCaMP6s and implanted with a gradient index lens to record calcium-dependent activity in Crh+-CeA cells. Cellular activity (n = 16-32 cells/mouse) was filmed using a miniature microscope during 5-minute offensive aggressive encounters in the home cage with a submissive intruder mouse or during 1-minute self-defense interactions with an aggressive conspecific. Crh+ CeA cell pools were identified based on their activity (maximum event threshold Z score 3) in relation to the initiation of an offensive attack. Additional CRH-ires-Cre males were given intra-CeA AAV5-hSyn-DIO-hM4D(Gi)-mCherry to target engineered drug-only activated designed inhibitory receptors (DREADD) or virus on Crh+-CeA - control neurons. Mice were systemically injected with vehicle or deschloroclozapine (0.02 mg/kg) five minutes before self-defense or offensive attempts at aggression. Behavioral videos from each test were collected and analyzed using a supervised machine learning pipeline. In particular, animal monitoring was performed in a multi-animal deep laboratory (maDLC; Lauer et al. 2022). The pose estimates generated by maDLC served as input to SimBA (Simple Behavior Analysis; Nilsson et al. bioRxiv), which used random forest classification to identify social focus, social contacts, and attacks. Sequences of graded behaviors were identified to quantify behavioral transition states, eg B. the likelihood of moving from social approach to social contact to attack.

Results:Crh+ CeA cells (n = 85) were divided into three sets: 41% were active in the 10 seconds prior to the start of the offensive attack, 32% were active during the attacks and 27% were inactive during the aggression. Chemigenic inhibition of Crh+ CeA cells selectively prevented offensive attacks without compromising social approach, contact, or adaptive self-defense by biting against an attacking intruder.

Conclusions:CeA Crh+ cellular activity is required for the transition from social contact to triggering offensive attacks. CeA-Crh+ cell activity was not required for self-defense bites, suggesting different neural circuits underlying offensive versus self-defense aggression. Closed-loop all-optical approaches are currently used to block the onset of seizures by using Crh+ CeA cell activity to remotely activate inhibitory optogenetics in real time.

Key words:Aggression, tonsil, corticotropin releasing factor (CRF), in vivo calcium imaging, chemogenetik

To disclose:Nothing to disclose.

Alyssa Roeckner*, Rebecca HInrichs, Timothy Ely, Sanne van Rooij, Nathaniel Harnett, Lauren LeBois, Vishnu Murty, Tanja Jovanovic, Stacey House, Samuel McLean, Karestan Koenen, Ron Kessler, Kerry Ressler, Jennifer Stevens

Emory University School of Medicine, Atlanta, Georgia, USA

Background:Amygdala hyperreactivity in early post-traumatic stress disorder is a demonstrable physiological correlate of later post-traumatic stress disorder (PTSD). Two areas of the amygdala in particular are known to play a role in threat response and PTSD: the basolateral amygdala (BLA), which is involved in threat processing and memory, and the central amygdala (CeA), which is involved in responses. autonomous to threats. However, there is little evidence of how the dynamics of amygdala reactivity over time relates to longitudinal PTSD symptomatology. Two opposing hypotheses are that (1) characteristic differences in amygdala threat response predict PTSD and persist over time, or (2) dynamic changes in threat response over time affect the results. Exploring how reactivity and functional connectivity in BLA and CeA persist or change over time after trauma may provide a better understanding of PTSD physiology and future treatment options.

Methods:As part of a larger multi-site study, AURORA, participants were admitted to the Emergency Department (ED) within 72 hours of a traumatic event. Participants witnessed an event involving actual or threatened serious injury, sexual violence or death, either through direct experience, witnessing it or learning from it. Participants were between 18 and 75 years old and spoke English. PTSD symptoms were assessed using the PTSD Symptoms Checklist for DSM-5 (PCL-5) at 2 weeks and 6 months after trauma. Left and right basolateral amygdala (BLA) and central amygdala (CeA) responses to threat (i.e., fearful > neutral faces) during fMRI were measured at 2 weeks (N = 305, 199 women) and 6 months after the trauma (N = 100 , 69 women). Anxious > neutral facial contrast scores for the four regions of interest (ROI) were tested for correlations with 2-week and 6-month PTSD symptoms. Task-based posterior functional connectivity (FC; anxious faces > neutral) was analyzed for regions showing significant associations in ROI analyses, using the Conn Toolbox with a voxel threshold of 0.005 to arrive at a FWE-corrected cluster threshold. end of 0.05 to allow .

Results:Left BLA response 6 months after trauma was negatively correlated with PTSD symptom severity at 2 weeks (r = -0.21, p = 04) and 6 months (r = -0.27, p = 006). Likewise, a decrease in left BLA reactivity from 2 weeks to 6 months predicted PTSD symptom severity at 6 months (r = -0.20, p = 0.04). There were no correlations between PCL-5 and CeA scores or right BLA reactivity at 2 weeks or 6 months. Subsequent FC analyzes were then performed using the left BLA as the seed region. At 2 weeks, current PTSD symptoms were associated with more positive HR in the cerebellum and more negative HR in the anterior and posterior cingulate, left middle frontal gyrus, and left supramarginal gyrus. At 6 months, current PTSD symptoms were associated with more positive HR involving the posterior cingulate gyrus, left inferior temporal gyrus, and left cerebellum, and more negative HR involving the right temporal pole and superior frontal gyrus.

Conclusions:The results suggest that PTSD symptoms persist in individuals who show strong reductions in left BLA threat reactivity in the months after trauma, supporting a dynamic model of changes in threat response after trauma in PTSD. The left BLA may experience a form of fatigue in people with chronic PTSD, possibly due to downregulation of norepinephrine or glutamate receptors in response to chronic stress. The CF results suggest that positive left BLA cerebellar connectivity is consistently associated with increased PTSD severity at all time points, whereas connectivity associated with increased PTSD severity between the left BLA and areas involved in the default-mode network ( posterior cingulate gyrus; anterior cingulate gyrus) starts negative at 2 weeks and becomes positive at 6 months. This suggests that the default mode network may play an important role in changes in left BLA reactivity for those with greater PTSD severity. The results support the importance of affective dynamics for PTSD risk and the need for further longitudinal neuroimaging studies.

Key words:PTSD, fMRI, basolateral amygdala, central amygdala, longitudinal MRI

To disclose:Nothing to disclose.

Jennie Garcia-Olivares*, Brittney Yegla, David Zweibaum, Chungping Yu

Supernus Pharmaceuticals Inc., Rockville, Maryland, EE. UU.

Background:Viloxazine ER (Viloxazine Extended-Release Capsules; Qelbree®) is a new FDA-approved non-stimulant treatment for attention deficit hyperactivity disorder (ADHD) in children (≥6 years) and adults. The therapeutic effect of viloxazine in ADHD has been attributed to inhibition of norepinephrine reuptake; however, their moderate potency (Ki = 0.630 µM) compared to conventional NRIs (eg, atomoxetine Ki = 0.005 µM) in binding to cells expressing human norepinephrine transporters (NETs) suggests alternative mechanisms of action. Recent in vitro data show that viloxazine has moderate affinity for the human serotonin (5HT) receptor isoforms [5-HT2C (Ki=1.5 µM), 5-HT7 (Ki=1.9 µM) and 5-HT2B ( Ki=3.4 µM)]. , but a clinically relevant effect on the 5-HT reuptake transporter SERT (Ki = 17.3 µM) was not expected. Furthermore, recently completed in vivo microdialysis experiments in rats show that viloxazine significantly increases 5-HT levels in the prefrontal cortex of rats at interstitial fluid (ISF) concentrations associated with clinically relevant plasma concentrations, an effect that is not can only be explained by NET inhibition. To take advantage of these emerging data and further elucidate the effects of viloxazine on serotonergic neurotransmission in vivo, we performed a positron emission tomography (PET) imaging study in cynomolgus monkeys. For this study, the radioligand agonist (to 5-HT2A and 5-HT2C), [11C]CIMBI-36, was used to evaluate the ability of viloxazine to induce changes in extracellular serotonin levels in cortical regions and brains. 5-HT2C receptors to be occupied in the choroid plexus

Methods:Four anesthetized cynomolgus monkeys received bolus infusions of viloxazine (3, 6, and 12 mg/kg) with a 6-week rest period between examinations. PET scans were performed at baseline and 30 minutes after infusion (1-2 scans per dose, 123 minutes per scan). [11C]CIMBI-36 was administered by bolus infusion immediately prior to the start of the study period. During image acquisition, arterial blood samples were obtained in eight moments from 2 to 90 minutes after the beginning of the scan for quantification of the metabolite [11C]CIMBI-36. Plasma concentrations of viloxazine were measured in blood samples collected at four time points 15-120 minutes after administration of viloxazine. PET images were analyzed using spatial processing to allow automated definition of regions of interest (ROI). The ROIs analyzed included the frontal cortex, choroid plexus and cerebellum. The choroid plexus was manually delineated. To estimate the total volume of distribution (TV) or ratio of [11C]CIMBI-36 in a target region, time activity curves were estimated from the data using the established multilinear analysis (MA1) modeling method. From the calculated VT values, the non-displaceable junctional potential (BPND) was calculated for each ROI, using the cerebellum as the reference region. The effect of viloxazine on radioligand displacement at 5-HT receptors is assessed based on the change in BPND between baseline treatment and viloxazine treatment.

Results:Administration of 3 mg/kg (n=1), 6 mg/kg (n=2), and 12 mg/kg (n=2) of viloxazine resulted in respective reductions in choroid plexus BPND of 60%, 76%, and 100% . %, respectively % (the latter represents complete blockage of [11C]CIMBI-36 binding). The same doses induced BPND changes of 25%, 15-32% and 38%-42% in cortical regions, respectively. At 3 mg/kg, the plasma free viloxazine concentration (Cmax) was 3.9 µM, which is close to the plasma free viloxazine concentration (Cmax) range of 2.2-3.3 µM observed with the therapeutic dose of 400 mg/kg. in children it was observed between 6 and 17 years.

Conclusions:Our results demonstrate a dose-dependent binding effect of viloxazine on the 5-HT2C receptor in the choroid plexus. The 60% displacement of radioligand by viloxazine at a clinically relevant dose (3 mg/kg) may be due to direct occupation of the 5-HT2C receptor by viloxazine. A dose-dependent displacement of [11C]CIMBI-36 by viloxazine in cortical regions was also observed. The action of viloxazine on cortical regions (rich in 5-HT2A receptors) may be due to direct occupation of 5-HT2A or increased synaptic release of 5-HT. An estimated viloxazine EC50 value for changes in BPND at the 5-H2A receptor is significantly greater than free viloxazine plasma concentrations at all doses tested. This suggests that the observed effect on radioligand binding is due to a viloxazine-mediated increase in endogenous 5-HT release rather than direct binding to the 5-HT2A receptor in the cortex. Overall, our experiments suggest that viloxazine at clinically relevant doses increases serotonergic neurotransmission in the PFC and acts on the 5-HT2C receptor, which may play a role in its effectiveness in treating ADHD.

Key words:ADHD, serotonin, PET imaging, PFC, viloxazine

To disclose:Supernus Pharmaceuticals Inc.: Employees (himself)

Gretchen Pifer, Karissa Gautier, Samantha Higley, Briana Karem, Kathleen Morrison*

West Virginia University, Morgantown, West Virginia, USA. UU.

Background:Adverse childhood experiences, particularly during the transition to adolescence, are one of the strongest predictors of mood dysfunction in women. As puberty is marked by dynamic hormonal changes and consequent reorganization of the brain, it represents a gender-specific window of vulnerability to negative experiences. We have previously shown that stress during puberty alters the hypothalamic-pituitary-adrenal (HPA) response to changes in the stress axis in adult female mice only during pregnancy and postpartum. In humans, pubertal difficulties resulted in an attenuated HPA response to a maternal separation stressor, which was associated with higher postpartum depression scores. We previously examined the reprogramming of pubertal stress in the paraventricular nucleus (PVN) of the hypothalamus, which triggers the HPA axis response. We found that pubertal stress resulted in an altered chromatin landscape and an altered transcriptophenotype in the PVN. Furthermore, we found that the pregnancy-associated hormone allopregnanolone is both necessary and sufficient to elicit the attenuated stress response in stressed pubescent women. Pubertal stress can lead to impaired maternal responsiveness and susceptibility to mood dysfunction. To advance our understanding of the risks that pubertal stress poses to altering future behavior, we began to examine different aspects of the formation and implementation of maternal behavior. Here, we examine pup-directed behaviors before (before mother) and after pregnancy and further explore the persistent programming of the stress response by pubertal stress. We hypothesized that pubertal stress would result in impairments in the ability to shape and display maternal behavior, as well as changes in chromatin and transcriptional landscape of maternal and stress-related brain regions.

Methods:Mice were exposed to chronic variable stress (CVS) from day 21 to 34 after birth using our previously established paradigm. The CVS consisted of two stressors (tactile, olfactory or auditory) per day. As adults, virgin females were left intact (no exposure) or exposed to new pups 2 hours a day for 4 days (maternal exposure). All females were tested for pup recovery in a maze 24 hours after the last maternal exposure, after which they were left intact for two weeks. The task of finding the pups was repeated and the brains were collected. Pup-directed behavior was analyzed during maternal exposure and pup retrieval task (n=34-35/group). To investigate molecular consequences related to maternal behavior, the medial preoptic area (mPOA) of the hypothalamus was removed from the brain, RNA was isolated, and quantitative PCR was used to measure gene expression (n=9-10/group) . In another group of mice, males and females were challenged with CVS as above and left intact until adulthood, when drug treatment and brain harvesting took place. Mice received allopregnanolone (100 ng/200 nl per side) or vehicle (25% w/v HP-β-CD) via intra-PVN cannulas 2 hours before brain harvesting. RNA was isolated from PVNs and gene expression was measured by quantitative real-time PCR (n=2-6/group). Data were analyzed using ANOVA with post hoc Tukey tests where necessary or Chi-square.

Results:Stressed pubescent adult females were more likely to show aggression towards pups than control females during challenges and behavioral tests (X2(1.69) = 6.031, p = 0.014). In mPOA, there was a significant interaction between pubertal stress and maternal exposure on Crebbp expression (p = 0.0034). In particular, there was an up-regulation of Crebbp in the mPOA of stressed pubescent women who had no maternal exposure compared to control women who had no exposure (p = 0.0225). This upregulation was associated with poor performance on the memory task, suggesting that pubertal stress disrupted Crebbp's canonical influence on memory. In PVN, preliminary results of intra-PVN administration of allopregnanolone recapitulated previous results, showing that stressed pubertal mice responded differently to allopregnanolone than control mice at the level of gene expression.

Conclusions:These findings provide new insights into the impact of adversity during adolescence on the lifetime risk of disturbed behavior. We found that stress during puberty resulted in disrupted pup-directed behavior and altered transcription in hypothalamic brain regions that regulate maternal and stress responses. Several areas of the hypothalamus are sensitive to pubertal stress, suggesting the potentially extensive and long-lasting consequences of adversity during this developmental period. Previous and ongoing work implicates disrupted histone acetylation as a possible mechanism for this persistent effect. This translation-relevant mouse model offers the opportunity to understand the molecular basis of the risk of behavioral and hormonal stress dysregulation following the stress of puberty.

Key words:Epigenetics, youth stress, risk and resilience

To disclose:Nothing to disclose.

Olivia Williams, Madeleine Coppolino, Cecilia Micelli, Melissa Perreault*

University of Guelph, Guelph, Canada

Background:Autism Spectrum Disorders (ASD) show an increasing prevalence in North America. Individuals are usually given a standard diagnosis of ASD, although the presentation and severity of symptoms vary across the spectrum, and sexual dimorphisms are also seen in age of onset, prevalence, etiology, and presentation. Animal models are often used to study certain aspects of ASDs, however, historically, women have been underutilized, leading to a lack of knowledge about possible sex-dependent mechanisms that may underlie the disorders. In this study, therefore, we aimed to characterize sexual dimorphisms in neuronal structure and function in the valproic acid model, a model commonly used to study idiopathic ASD.

Methods:Pregnant Sprague-Dawley rats were injected with VPA (500 mg/kg) or saline i.p. injected. the day of pregnancy 12.5. To assess changes in neuronal structure and function in vitro, cortical and hippocampal tissues (HIP) were dissected from postnatal day 0-1 male and female pups. In DIV 21, neurons were stained with microtubule-associated protein-2 (MAP-2) for Sholl analysis or neural systems activity was assessed on a multiple electrode array (MEA) (Axion Biosystems) for 30 min. To assess behavioral sexual dimorphisms, adolescent male and female rats (PND 31-38) were subjected to behavioral tests in the three-chamber social test, novel object recognition (NOR), object location (OL), and elevated plus maze ( EPM). After testing, rats were bilaterally implanted with stainless steel electrodes in the medial prefrontal cortex (PFC) and dorsal hip. After recovery, local field potential recordings were made in awake animals that moved freely for 30 min (N=10 rats/group). Chronux for MATLAB software was used to evaluate spectral power in each frequency band within each region.

Results:: Sholl's analysis showed sex-dependent VPA-induced changes in the mean number of intersections in cortical neurons and HIP, which depended on the distance from the soma. Only female cortical VPA neurons showed reduced length compared to sex-matched controls (p = 0.029). When neural activity was assessed, sex-specific changes in system function were evident in both the VPA group and control neurons. Male-derived cortical control neurons showed mean increase in firing and firing compared to female-derived control neurons (p<0.001), although this was reversed for VPA neurons (p<0.001). VPA neurons from both sexes also showed increased firing and popping compared to their same-sex controls (p < 0.001). Male-derived cortical neurons had a significantly higher synchrony index compared to females (p < 0.001), although this effect was lost between sexes in the VPA group. Overall, VPA neurons showed significantly greater synchrony compared to controls [F(1.62)=58.06, p<0.001]. In HIP neurons, the control firing rate of male-derived neurons was higher than that of females (p < 0.001), an effect that was lost with exposure to VPA. Only female-derived VPA cells showed increased activation compared to their sex-matched controls (p < 0.001). In contrast to the cortex, burst activity decreased in VPA-HIP neurons of male origin (p < 0.001) and increased in the female VPA group (p < 0.001) compared to sex-matched controls. No significant differences were observed between groups in the synchronicity index. In vivo behavioral tests in adolescence revealed gender-specific ASD-like characteristics in the VPA group. Rats exposed to VPA showed increased anxiety in MPE compared to sex-matched controls (p =0.005), showed deficits in the NOR task (p <0.001) and showed deficits in social index scores (p =0.007). ), although they were more sociable than VPA-treated male rats (p = 0.014). In contrast, VPA men showed deficits in both the OL task (p = 0.012) and social index score (p = 0.036) compared with male controls. After behavioral testing, neural oscillation activity was examined. Female VPA rats showed significantly higher PFC delta power (p<0.001) and reduced theta power (p<0.001) compared to female controls and had higher delta (p<0.001) and reduced theta power (p<0.001) compared to VPA males. In the high frequency bands, VPA females had lower beta, low gamma, and high gamma (p<0.001, p=0.012, and p<0.001, respectively) compared to VPA-exposed males, effects that were not evident between sexes. in controls In HIP, differences were observed selectively in the low frequency, delta and theta bands, where VPA females compared to VPA males had significantly higher delta power (p = 0.037) and lower theta power (p = 0.008). ) than control females. When the consistency between PFC and dHIP was examined, VPA females showed lower delta consistency (p = 0.029), while VPA males showed no change compared to sex-matched controls.

Conclusions:These preclinical results identify important gender differences in neuronal structure and function in vitro, and in the function and behavior of the PFC and HIP systems in vivo in a model commonly used to study ASD. In particular, the impact of VPA exposure on PFC and HIP was more significant in women exposed to VPA. Taken together, these results show clear sexual dimorphisms in the VPA model that may be relevant to the sexual dimorphisms observed in TEA. This work also underscores the critical need to employ both sexes when using animal models in the study of neuropsychiatric disorders.

Key words:autism, neural oscillations, dendritic branching, behavior, systems neuroscience

To disclose:Nothing to disclose.

Cassandra Kooiker*, Matthew Birnie, Yuncai Chen, Tallie Z. Baram

University of California - Irvine, Irvine, California, USA

Background:Early life adversity (ALS) is associated with poor cognitive and emotional health, including increased risk of a variety of mood disorders, including depression and substance use disorders. Many of these disorders are characterized by deficits in reward-related behavior, and we have found that the same deficits are induced by rodent models of ALS. However, the brain regions and processes underlying these long-term effects of ALS remain largely unknown. The paraventricular nucleus of the thalamus (PVT) is an important center of the reward circuit, which encodes emotionally salient and distant experiences to influence future motivated behaviors. We hypothesize that PVT encodes adverse experiences as far back as the early postnatal period in mice, and that ALS-activated PVT neurons subsequently contribute to changes in reward-related behavior in adults.

Methods:We used TRAP2 mice that we exposed to mock ALS for one week between postnatal days 2 and 9 in a resource-limited cage. We induced the TRAP2 system using tamoxifen at P6 and caused Cre-dependent recombination in activated neurons during P6-P8. This leads to a permanent labeling of neurons that were activated during that time. We validated our results using routine cFos immunohistochemistry in WT mice. We then inhibited these ALS-involved neurons during an adult reward-seeking task with the aim of enhancing ALS-induced changes in reward-seeking behavior.

Results:ALS robustly and selectively activates significantly more PVT neurons than typical rearing conditions (p = 0.0154, unpaired t-test; N = 24), and a large proportion of these ALS-committed PVT neurons express CRFR1 (40% vs. 20% in controls, p < 0.001, unpaired t-test, N = 12). Silencing of ALS-activated PVT neurons during reward-related tasks in adult female mice improved the observed ALS-induced changes in reward-seeking behavior (N = 16).

Conclusions:PVT is robustly and almost exclusively activated in response to emotionally salient events in newborn mice, and inhibition of these neurons involved in ALS enhances ALS-induced changes in reward seeking. Thus, PVT stands ready to make a potential contribution to deficits in reward-related behavior after ALS.

Key words:Paraventricular nucleus of the thalamus, adversities in early life, mood disorders, reward circuits, motivated behavior

To disclose:Nothing to disclose.

Natasha Fowler, Allison Milian, Bendersky Cari, Mason Andrus, Deena Walker*

Oregon Health and Science University, Portland, Oregon, EUA

Background:Adolescence is a rewarding phase of development, and social experiences in adolescence have robust effects on rewarding behavior. Reduced social connections increase the risk of substance use disorder. Our laboratory and others have shown that adolescent social isolation (SI) alters cocaine-related behavior and transcription in adulthood, but little is known about how SI interrupts reward circuitry development to influence behavior.

Methods:We hypothesize that SI disrupts the developmental profiles of GABAergic and glutamatergic systems in 3 brain regions (prefrontal cortex - PFC, basolateral amygdala - BLA and ventral hippocampus - vHIP) to affect adult behavior. Animals were postnatally isolated (P)22-P42 and then housed in groups. Male and female mice were sacrificed on the day of isolation (P22), isolation from the medium (P32), housing (P42) and on day P72. PFC, BLA and vHIP hits for RT-qPCR (n = 6-8 animals per group; total: ~150 animals) were collected from 24 GABAergic and glutamatergic genes. Reward-related behaviors, including tasty food intake and cocaine-related place preference, were also assessed in a subset of adult men and women.

Results:Preliminary behavioral analyzes indicate a greater preference for tasty food and cocaine in men. Three-way ANOVA for sex, SI and age revealed the main effects or interactions (p <0.05) for glutamate receptor subunits (Gria1 and 2; Grin1, 2a, 2b and 2c) and glutamate transporter (Slc17a6) in 3 brains. regions. Although region-specific effects were observed, a post hoc analysis revealed that expression of many glutamatergic genes was increased by SI in males at P32. However, GABAergic genes were affected only in PFC. Three-way ANOVA revealed a significant interaction between sex X age X SI for GABA A receptor subunits (Gabra1, Gabrg1; p<0.05), GABA transporter (Slc32a1; p=0.006) and Gad2 (p=0.001) . Post hoc analyzes showed a significant decrease in P32 expression in men.

Conclusions:These data suggest that SI leads to a gender-specific enhancement of the arousal system through reward circuits in men and a concomitant suppression of the GABAergic system (PFC only). These findings provide a gender-specific mechanism by which the SI can reprogram reward circuits to affect adult behavior.

Key words:Mesolimbic reward circuits, gene expression, adolescent stress, GABA-A receptors, NMDA glutamate receptors

To disclose:Nothing to disclose.

Andrew Nelson, Amanda Catalfio, Julie Philippe, Lia Min, Rene Caballero-Floran, Kendall Dean, Carina Elvira, KImberly Derderian, Henry Kyoung, Atehsa Sahagun, Stephan Sanders, Kevin Bender, Paul Jenkins*

University of Michigan School of Medicine, Ann Arbor, Michigan, USA

Background:Dysfunctions in sodium channels and their ankyrin structural partners have been linked to neurodevelopmental disorders, including autism spectrum disorder (ASD). In particular, the genes SCN2A, which encodes the sodium channel NaV1.2, and ANK2, which encodes ankyrin-B, are strongly associated with ASD. Recent studies indicate that ASD-associated haploinsufficiency in Scn2a affects dendritic excitability and synaptic function in neocortical pyramidal cells, but how NaV1.2 is anchored in dendritic regions is unknown.

Methods:Here we combine cellular and molecular biology with electrophysiology and two-photon imaging to show that the protein products of these two ASD risk genes, SCN2A and ANK2, interact in neocortical pyramidal cell dendrites to mutually regulate dendritic excitability.

Results:Using a novel epitope-tagged NaV1.2, we found that NaV1.2 colocalizes with ankyrin-B in the dendrites of mature neocortical neurons. Ankyrin-B deletion abolished dendritic localization of NaV1.2. Furthermore, dendritic ankyrin-B loss was not compensated for by other members of the ankyrin family, suggesting that ankyrin-B plays a unique role in this neuronal compartment. Ex vivo studies have shown that Ank2 haploinsufficiency results in intrinsic synaptic and dendritic deficits very similar to those seen in heterozygous Scn2a neurons.

Conclusions:Therefore, these results suggest that deficits in dendritic excitability may be a common point of convergence in ASD, with direct convergence between two high-risk genes SCN2A and ANK2.

Key words:SCN2A, dendrites, excitatory synapses, autism spectrum disorders

To disclose:Nothing to disclose.

Shelby Ruiz, Lambertus Klei, Bernie Devlin, Matthew MacDonald*

University of Pittsburgh, Pittsburgh, Pennsylvania, USA

Background:Despite the variety of symptoms and severity of autism spectrum disorders (ASDs), spinal cord changes are seen in many genetic models (ASDs) and affected tissues. Genetic studies of ASD have identified rare variants and shared loci that involve synaptic protein networks critical for spinal cord formation and stabilization. Furthermore, transcriptomic studies of cortical regions in ASD found altered expression of synaptic genes. However, transcriptome changes are not always well correlated with synaptic protein levels, and a study of the synaptic proteome in tissues from patients with ASD has yet to be performed. Therefore, it is currently unknown to what extent transcriptomic changes manifest at the synapse in ASD patients and contribute to changes in the spine. Here, in a preliminary study, we examined synaptic protein levels in primary visual cortex tissue of postnatal ASD and in corresponding neurotypical individuals.

Methods:Postmortem primary visual cortex tissue from 31 pairs of ASD and neurotypical individuals (ages 4 to 33 years) matched for sex, age, and postmortem interval was obtained from the NIH NeuroBioBank branch of the University of Maryland. Synaptosome enrichments were performed with SynPER. Synaptosomes were trypsinized, labeled with TMT, fractionated and analyzed in an Orbitrap Eclipse with SPS and real-time search. The identification and quantification of peptides and proteins was performed using Proteome Discoverer 2.5.

Results:7577 proteins were identified in synaptosome enrichments in all subjects. Of these, 4601 (including 115 ASD risk gene products, SFARI) with > 50% existing reputation were quantified and included for statistical comparison with age and diagnosis. Synaptosome levels of 1462 proteins were significantly associated with age (q > 0.05); with 860 decreasing and 539 increasing during postnatal development. Interestingly, the 860 proteins that decreased with age were significantly enriched for the terminal GO synapse in SYNGO (q=5.82e-15, relative to the 7577 proteins quantified), while the same occurred with the proteins that decreased with increasing age. . It's not the case. Similarly, proteins that decreased with age included 40 ASD risk genes, while proteins that increased included only 4 ASD risk genes. Of the ASD risk genes analyzed, only one, receptor-type protein tyrosine phosphatase F, differed significantly between ASD and neurotypical individuals (HR = 1.2, q > 0.05). We are currently studying protein expression and phosphorylation in this cohort.

Conclusions:Synaptic protein levels are strongly altered during postnatal development in the human primary visual cortex. Decreased synaptosome levels of canonical synaptic proteins and ASD risk genes likely reflect the reorganization and loss of synaptic proteins that accompany synaptic pruning in postnatal development and the importance of ASD genes in prenatal synaptic development. Our results further suggest a role for receptor-type protein tyrosine phosphatase F, which may be involved in postsynaptic organization and regulation of tyrosine kinases, in postnatal synaptic changes in ASDs.

Key words:Autism, proteomics, postmortem brain tissue

To disclose:Nothing to disclose.

Alan Lewis*, James Bauer, Leann Seanez, Catherine Cerroni, Yuval Guetta, Sam Kwon, Alex Steiner

Vanderbilt University Medical Center, Nashville, Tennessee, EUA.

Background:Localized hyperactivity of the anterior hippocampal formation is a reproducible finding in patients with early psychosis. Identifying the causes and consequences of regional hippocampal pathology at the molecular and cellular level of resolution in living humans is challenging and supports the use of animal models with aberrant neurodevelopment that predispose to psychotic disorders such as 22q11.2 deletion syndrome. Using a mouse model of 22q11.2 deletion syndrome, we tested whether mossy cells (MC), a glutamatergic neuron in the dentate gyrus (DG) that is prone to loss in other hippocampal hyperexcitability disorders such as temporal lobe epilepsy, are reduced in number. in adolescent and adult mice. We then performed RNA sequencing to examine molecular signaling pathways with potential relevance to localized MC changes.

Methods:Df(h22q11)/+ and D2-Cre mice were purchased from Taconic Biosciences and UC Davis, respectively, and bred at the Lewis Lab at Vanderbilt. D2-Cre;22q/+ or D2-Cre;+/+ males and females were sacrificed at P28 (juvenile) or >12 weeks of age (adult), followed by immunohistochemistry for the MC GluR2/3 marker, confocal microscopy and analysis.Manual. blind cell counts for genotype. Statistical analysis of cell number was performed using the t-test (two-tailed or one-tailed when testing predicted reduction) or ANOVA with Sidak's multiple comparison test. RNA sequencing was performed by Vanderbilt VANTAGE Genomics Core using RNA extracted from 12-week-old Df(h22q11)/+ and  + /+ ventral hippocampal tissue. Library preparation was performed with a ribo-depleted total RNA library preparation kit, and 150 bp end-paired sequencing was performed on the Illumina NovaSeq 6000, followed by differential gene expression analysis and p-value correction for multiple comparisons .

Results:The number of mossy cells was reduced in ventral but not dorsal DG of D2-Cre adults; 22q/+ mice compared to D2-Cre; littermates +/+ (region x genotype interaction: F( 1, 19) = 9.087, p =0.007; retest between genotypes: dorsal region: p=0.87; ventral region: p=0.001; N=10-11 /group). However, in this group of mice, there was no reduction in the density of granular cells in the DG (p=0.82) or in the number of parvalbumin+ interneurons in the DG (p=0.73). We then examined whether this reduction was also present during adolescent development and found that ventral MCs were reduced in 28-day D2-Cre mice; 1-tail t test). RNA sequencing of adult ventral hippocampal tissue (N = 3 Df(h22q11)/+, 3 mice +/+) showed a significant reduction in 18 of 27 genes within the Df(h22q11)/+ deletion. This analysis also identified a significant reduction in Fos and JunB, two members of the activator protein 1 (AP-1) transcription factor family not encoded in the Df(h22q11)/+ deletion region. Immunohistochemistry showed that Fos and JunB were expressed in ventral DG-MCs in wild-type mice.

Conclusions:These studies demonstrate that MCs are reduced in number in mice with a genetic deletion orthologous to the human 22q11.2 deletion syndrome. This deficit occurs at least as early as P28, arguing that the loss is not due to cell death later in development. Several questions arise from this study: 1. Is the reduction in ventral MC due to a parental population problem and/or a disorder of autonomous cell development? 2. Perform abnormalities in DG networks early in development, such as B. an imbalance between excitation and inhibition, to non-cellular autonomic deficits in MC maturation or stability? 3. Are AP-1 transcriptional networks really disrupted in MCs as opposed to other cell types? If so, is this cell autonomous or non-autonomous? If ventral MC loss per se contributes to cognitive or other aspects of the 22q11.2 deletion syndrome, exploration of the mechanisms underlying regional MC loss may contribute to a more general understanding of the pathological disorders. Molecular and cellular factors in the hippocampus that predispose to psychosis.

Key words:Hippocampus, 22q11 deletion syndrome, dentate gyrus, RNA sequencing, psychosis

To disclose:Nothing to disclose.

Dennisha King*, Judy Cameron, Ania Majewska, Julie Fudge

University of Rochester, Rochester, New York, USA

Background:The amygdala of non-human primates is remarkably similar to that of humans and develops over a long period of time after birth. This long evolution means that environmental events can affect neural growth and connectivity during the first few years of life. Our group and others, including those working with human postmortem tissue, have shown that the primate amygdala has a lifetime supply of immature postmitotic neurons (the paralaminar nucleus, PL) that surround the principal basal nucleus (MPG) and interdigitate. with him. 🇧🇷 While most PL neurons are immature at birth, a proportion have developed mature profiles by adolescence, indicating ongoing differentiation. Bpc, on the other hand, is largely populated by mature neurons based on immunocytochemical markers. Although we are beginning to understand normal neural maturation in LP, the role of microglia, the brain's immune cells, in the development of LP is unknown. However, microglia are crucial for differentiating progenitor cells into neurons, removing excess neuroblasts, and pruning synaptic contacts. Each of these functions is associated with different morphological and molecular signatures. Microglia phagocytize unnecessary neuronal progenitors (large microglial soma, short thick, clustered processes), prune neuronal synapses (small microglial soma, branched processes, relatively distributed), and release growth factors that support neuronal differentiation.

Methods:As a first step in characterizing the role of microglia in the development of LP, we examined microglia in 3-month-old (infant) and 4-year-old (juvenile) monkeys (n = 4/group) in both LP and macaques. adjacent BPC. We immunostained 1:12 sections through the tonsil for Iba1 (ionized calcium-binding adapter molecule 1), which is a microglia marker. The PL and Bpc region was identified using adjacent sections stained for mature and immature neurons. High power photomicrographs were then taken blindly, case by case, at similar levels. We then analyzed morphological features (microglia density, clustering, and size/soma shape) using FIJI/Image J. Studies on microglial branching (Sholl) and immunostaining for chemical markers of synaptogenesis are ongoing.

Results:Mean LP microglia density was 37% higher in adolescents (390 microglia/mm2) compared to infants (267 microglia/mm2; p = 0.0143), with no difference in density between medial, central, and lateral. Bpc microglia density was also higher in adolescents (341 microglia/mm2) than in infants (290 microglia/mm2), although in a smaller percentage: 16% (p = 0.0143).

The clustering index (distance), which measures the distribution of microglia considering density (calculated as: (mean distance from nearest neighbor)2 * microglia density), was similar in LP between juvenile groups (p = 0.395 ). On the other hand, the spacing index was 10% smaller in the Bpc adolescent (0.473) compared to the infant (0.530), indicating closer spacing (p = 0.0277).

Conclusions:These preliminary data show an increase in the number of microglials from infancy to adolescence in PL and Bpc. There is also an increase in Bpc microglia clustering in adolescence, suggesting potentially greater microglial interactions with neurons. Ongoing data analysis will determine whether differences in increased microglial density in each region are clues associated with regional synaptogenesis.

Key words:Paralaminar nucleus, immune markers, cytokines, synapses, schizophrenia, autism, basal nucleus

To disclose:Nothing to disclose.

Francisco Castellanos*, Paige Cervantes, Rebecca Shalev, Greta Conlon, Yuliya Yoncheva, Lauren Robinson, Glenn Hirsch, Andrea Troxel, Orrin Devinsky

NYU Grossman School of Medicine, New York, New York, USA

Background:Autism spectrum disorder (ASD) is widespread (~2.3% of children) and specific pharmacological treatments are lacking. Anecdotal reports and a placebo-controlled study (using a 20:1 ratio of cannabidiol (CBD) to THC; Aran et al., Molecular Autism, 2021) suggest that CBD may be helpful for some autistic children. CBD has been approved by the US Food and Drug Administration for the treatment of refractory seizure disorders in children and has been well tolerated. We conducted an ongoing open-label study of pharmaceutical-grade, THC-free, FDA-approved CBD in seizure-free children and adolescents with at least average IQ as a basis for hypothesis generation and dose and outcome selection. in future controlled studies. 🇧🇷 CBD is provided free of charge by JAZZ Pharmaceuticals, which was not involved in the design of the study or the analysis or reporting of the results.

Methods:Nineteen adolescents aged 7 to 17 years (M = 11.3 ± 2.9) with ASD have an ongoing 6-week open-label Phase 2 study with 98% CBD (100 mg/mL) at 3, 6 or 9 mg /kg/day completed; Target N = 30 [NCT03900923]. The dose was determined according to an optimal Bayesian range design, starting with a dose of 6 mg/kg/d, with an initial expectation of a response rate of 60%. Inclusion criteria were a confirmed diagnosis of ASD, fluency, IQ ≥ 80, Social Response Scale (SRS-2) total T-score ≥ 66, and Clinical Global Impression-Severity (CGI-S) scale score. ≥4 on an individualized target symptom domain, identified at baseline by clinical consensus informant report, rating scales, and clinical observation. Response was defined as a CGI Improvement Score (CGI-I) ≤ 2 in the target domain. Adverse events (AEs) were rated at weeks 2, 4 and 6 using the UKU Physician Administered Adverse Reaction Rating Scale, Patient Version 5 for Dyads and at weeks 1, 3 and 5 by calls from the coordinator to parents. Clinical consensus determined the association of AD with treatment. In response to COVID-19, all screening procedures and assessments (with the exception of physical exams and blood tests to monitor safety) were conducted via secure virtual conference calls. The surveys were managed securely through the REDCap software. Plasma CBD levels and clinical laboratory values ​​were obtained in the last session.

Results:Demographics: We enrolled 18 men and 1 woman. Complete IQ scores ranged from 81 to 136 (M = 104 ± 17). Seventeen had comorbid psychiatric diagnoses: ADHD - Combined (n = 12), ADHD - Inattentive (n = 4), Obsessive-Compulsive Disorder (n = 4), Anxiety (n = 3), and Other Specific Disorders and Impulse Control Disorders ( n=2). Participants' racial and ethnic identities included white (n=12), white/Hispanic (n=5), Asian (n=2), black/African-American (n=1), mixed race (n=2), racial unknown/Hispanic (n=1) and race/ethnicity unknown (n=1).

All 19 enrolled participants completed the study; a total of eight were classified as responders (42%); The response rate was dose dependent and ranged from 17% with 3 mg/kg/d (n=6) to 44% with 6 mg/kg/d (n=9) and 75% with 9 mg/kg. /d ( n = 4; this phase is still ongoing). Dose correlates with CGI-I (r(18)=-0.43, p=0.05). CGI-S scores improved significantly from before (M=4.68±0.48) to after treatment (M=3.95±0.78), t(18)=3.98, p=<0.001; Cohen's d = 0.92; CI 95% [0.37; 1.44]. In a post hoc analysis, we found that none of the five participants taking stimulants for ADHD responded to CBD, while 8 of the 11 (73%) who had ADHD but were not treated with stimulants responded (Fisher's exact p = 0.013) . 🇧🇷

A total of 83 AEs were reported; 79 were classified as mild, 3 mild to moderate and 1 moderate. Of the 30 AEs considered by medical consensus to be related to CBD, none were related or unexpected. There were 17 unexpected AEs, all considered unrelated. Laboratory tests of liver function and complete blood count were not affected by CBD. Plasma levels of CBD after 6 weeks of treatment ranged from 2.4 ng/ml to 430.6 ng/ml and were dose-related (r(18)=0.46, p=0.05), but not with the CGI-I (r(18)=-0.19).

Conclusions:CBD is well tolerated and appears to be beneficial for autistic youth, albeit with a lower than expected overall response rate. We speculate that although average doses of CBD in the community are 2 to 3 mg/kg/day, placebo effects may have disappeared due to informal testing by families and facilitated by the legalization of CBD (DiLiberto et al., 2022). Our experience suggests that higher doses tend to be beneficial and, when benefits are observed, they last for several weeks. Unexpectedly, we observed a high response rate (73%) in adolescents with comorbid ADHD who were not treated with stimulants. These results are consistent with Seeman's 2016 observation (in Translational Psychiatry) that CBD has partial agonist properties at striatal D2 receptors, comparable to aripiprazole, one of two atypical neuroleptics approved for the treatment of irritability in pediatric autism. We plan to continue enrollment until our IRB-approved 30-year delay is reached, with an emphasis on ASD+ADHD comorbidity in the remaining participants.

Key words:Delta9-tetrahydrocannabinol, cannabidiol, autism spectrum disorder and related syndromes, stage 2, attention deficit hyperactivity disorder

Disclosures: BOL Pharma: Advisory Board (own expense), Frontiers Media: Fees (own expense)

Luis Farhat*, Emily Behling, Angeli Landeros-Weisenberger, Jessica Levine, Pedro Macul Ferreira de Barros, Ziyu Wang, Michael Bloch

Faculty of Medicine FMUSP, University of Sao Paulo, Sao Paulo, Brazil

Background:Tourette syndrome (TS) is a neurodevelopmental disorder characterized by multiple motor tics and at least one phonic tic, with onset in childhood or adolescence and lasting more than 1 year. Practice guidelines from the American Academy of Neurology (AAN), the American Academy of Child and Adolescent Psychiatry (AACAP), and the European Society for the Study of Tourette Syndrome (ESTSS) agree that medication should be offered to people whose symptoms of TS are moderate to severe, persistent and associated with deterioration. However, there is no consensus on which drugs should be used as first-, second-, or third-line treatment. Inconsistencies in treatment recommendations stem from the fact that double-blind randomized controlled drug trials (RDBCTs) in TS are rare and based on small samples, creating difficulties in trying to determine the direct effects of different drugs. Network meta-analyses facilitate the assessment of the comparative effectiveness of two or more interventions, even if they have not been studied in direct RDBCT, and are required as the highest level of evidence for treatment guidelines. To fill this gap, we performed a systematic review and network meta-analysis of drug treatments evaluated in RDBCT for the treatment of adolescents with TS.

Methods:We searched PubMed, the Cochrane Central Register of Controlled Trials, Web of Science, Embase, PsycINFO, and the WHO International Trials Registry Platform, including ClinicalTrials.gov, from database inception to 19 February 2021. manually search the US Food and Drug Administration, European Medicines Agency, and relevant drug manufacturer websites, as well as references to systematic reviews and previous guidelines, to search for additional studies. Randomized, double-science controlled trials (RDBCT) were included that included children and adolescents (ages ≥ 4 and ≤ 17 years), adults (≥ 18 years) or both with a primary diagnosis of TS according to the Diagnostic and Statistical Manual of Mental ilnesess. (DSM-III/III-R/IV/IV-TR/5), the International Classification of Diseases (ICD-9/10/11) or the Chinese Classification of Mental Disorders, 3rd Edition (CCMD-3). We do not restrict eligibility based on medications as long as they were administered as monotherapy. For the outcome, we considered efficacy, measured as change in severity of tic symptoms; Tolerance, measured as the proportion of participants who discontinued the study due to side effects; and acceptance, measured by the proportion of participants who withdrew for any reason. Pairs of investigators independently reviewed records to select studies and extract data. We performed a random effects network meta-analysis in a frequentist environment. We assume a common variance of heterogeneity τ2 between the different treatment comparisons. We quantify heterogeneity as low, moderate, or high by comparing τ2 with its empirical distribution. We assessed inconsistency globally (design-by-treatment interaction) and locally (indirect evidence separated from direct, SIDE). All analyzes were performed in R using the meta or netmeta packages. The risk of bias of the RDBCTs was assessed using the Cochrane tool. We drew comparison-adjusted funnel plots to examine publication bias. We assessed the certainty of network meta-analyses results using the Network Meta-Analysis Confidence Framework (CINeMA).

Results:Of the 12,088 selected datasets, 39 RDBCTs with 4,578 participants (mean age [SD] 11.83 [SD] 11.83 [4.55]; 80% male) were included in the network meta-analyses. Ratings for heterogeneity, inconsistency, and publication bias were incorporated into the evidence quality ratings. Regarding efficacy, aripiprazole (SMD -0.60; 95% CI -0.83, -0.38), haloperidol (SMD -0.51; 95% CI -0.88, -0.14), olanzapine (SMD -0.83; 95% CI -1.49, -0.18), pimozide (SMD -0.48; 95% CI -0.84, -0.12), risperidone (SMD -0.66 ; 95% CI -0.98), clonidine (SMD -0.20; 95% CI -0.37, -0.02) and ecopipam (SMD -0.34, -0.63, -0.06) resulted in greater changes in tic symptom severity than placebo (moderate certainty evidence). There were no significant differences between the antipsychotic medications in the direct comparison (low to very low certainty evidence), but aripiprazole (SMD -040, 95% CI -0.69, -0.12) and risperidone (SMD -0.46; 95%). %CI -0.82, -0.11) were more effective than clonidine (moderate quality evidence). With regard to tolerability and acceptability, there were no relevant findings for any of the effective drugs compared with each other or with placebo (low to very low certainty of evidence).

Conclusions:Overall, our results support that antipsychotics are the most effective drugs in the treatment of TS. As there are no differences in efficacy between pairs of antipsychotics based on current data, the choice of antipsychotics should be based primarily on their tolerability. However, it is controversial whether antipsychotics should be used as first-line pharmacological interventions in the treatment of TS due to their potential for toxicity and the potential for serious and somatic adverse events, particularly in vulnerable populations such as children and adolescents. Although alpha2 agonists are less effective, their risk/benefit ratio may be higher due to less worrisome side effects.

Key words:Tourette's Syndrome, Psychopharmacotherapy, Meta-analysis

To disclose:Nothing to disclose.

Helen Heusslar, Jonathan Cohen, Caroline Buchanan, Carol O'Neill, Stephen O'Quinn, Terri Sebree, Steven Siegel*

Keck School of Medicine, USC, Los Angeles, California, USA.

Background:22q11.2 deletion syndrome (22q) is caused by a microdeletion of region 11.2 on the long arm of chromosome 22 and is the most common recurrent continuous gene deletion syndrome, estimated to occur in approximately 1 in 4000 live births. 22q is associated with several developmental abnormalities, including congenital heart defects, palate and throat defects, and immunodeficiency. Behavior problems, autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), and mood disorders are common in children who have 22q. ZYN002 is a pharmaceutically manufactured transdermal cannabidiol gel under development for the treatment of behavioral symptoms of 22q, fragile X syndrome and ASD. INSPIRE was an open-label Phase 2 study that evaluated the safety/tolerability and efficacy of ZYN002 in children and adolescents aged 4 to <18 years in the treatment of behavioral and anxiety symptoms in 22q.

Methods:Males and females in 22q, confirmed by genetic testing, with or without autistic features, a Clinical Global Impression Score (CGI-S) ≥ 4, and a Revised Pediatric Anxiety Rating Score (PARS-R) ≥ 22q were included. 10. Patients weighing ≤ 35 kg received 250 mg/day and patients weighing > 35 kg received ZYN002 500 mg/day in divided doses every 12 hours in addition to current stable therapy for 14 weeks. For patients with <25% improvement from baseline on the irritability subscale of the Aberrant Behavior Community Checklist (ABC-C) at week 6, the dose may be increased to 500 mg/day or 750 mg/day, depending on weight. Safety assessments included adverse events, vital signs, laboratory values, and electrocardiograms (ECG). Efficacy assessments included changes from baseline on the Anxiety, Depression, and Mood Scale (ADAMS), ABC-C, PARS-R, CGI Improvement (CGI-I), and Infant Sleep Questionnaire (CSHQ). A qualitative survey of caregiver-reported behavior problems was also collected.

Results:Twenty patients were included, 60% male, with a mean age of 9.9 years (5 to 15 years). During the treatment period, 17 patients completed participation and 3 withdrew. Sixteen patients had evaluable efficacy assessments at week 14, and 13 patients entered a 6-month extension period. Statistically significant improvements were observed on the ADAMS, ABC-C and PARS-R scales. The mean change and mean/median percent improvement from baseline on the ADAMS were as follows: total score -18.4, 45.3%/43.0%, p=0.0005; General anxiety -5.4, 43.6%/48.8%, p = 0.0005; Depressed mood -4.3, 50.3%/52.8%, p = 0.0033; Social avoidance -4.4, 41.3%/50.0%, p = 0.0084; Compulsive behavior -1.9, 64%/66.7%, p = 0.0037; Manic/hyperactive behavior -3.1, 38.2%/27.4%, p = 0.0032. Mean change and mean/median percentage improvement from baseline on the ABC-C were as follows: Social isolation -6.4, 27.6%/46.4%, p=0.011; Inappropriate language -1.8, 18.3%/50.0%, p = 0.0166; Stereotyped behavior -2.3, 52.1%/58.3%, p = 0.0155; Irritability -8.4, 36.3%/39.6%, p = 0.0055; Hyperactivity -7.6, 16.5%/38.1%, p = 0.0091. Mean change and mean/median percent improvement from baseline on the PARS-R were: total score -6.2, 40.6%/40.0%, p=0.0005. Twelve of 16 patients (75%) were rated as "improved", "much improved" or "much improved" at week 14, with 62.5% scoring "much improved" or "much improved" on the CGI-I. Three patients reported treatment-emergent adverse reactions, all of which were mild application site adverse reactions that were transient and resolved with continued administration. One patient discontinued treatment due to side effects unrelated to ZYN002. No serious adverse events or clinically significant changes in vital signs, ECG or laboratory values ​​were reported.

Conclusions:INSPIRE provides early evidence of a positive risk-benefit profile for ZYN002 in improving behavioral and anxiety-related symptoms in 22q children and adolescents when given in addition to a stable standard of care. More studies are needed.

Key words:22q11 deletion syndrome, Adolescence, Neurodevelopmental disorders, Cannabidiol, CBDV, Translational models, Clinical trials

To disclose:Zynerba: Counselor (auto)

Craig Erickson*, Lauren Schmitt, Lisa DeStefano, Rui Lui, Lauren Ethridge, Kelli Dominick, Rebecca Shaffer, Meredith Will, Elizabeth Smith, John Sweeney, Ernest Pedapati

Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, EUA.

Background:Fragile X Syndrome (FXS) is the most common single genetic cause of autism and the most common inherited form of developmental disabilities. Despite fragile X knockout (KO) animal models available, translation of preclinical treatment success has yet to result in successful approved treatments in humans with FXS. We discovered molecular variations in fragile X messenger ribonucleoprotein (FMRP) expression in men with FXS, which clinical genetic testing described as a full methylated mutation (CGG expansion) in the FMR1 gene. We added the peripheral blood FMRP assay to recent FXS-targeted drug studies to characterize patient-specific molecular pathology. We describe initial experience with this approach in placebo-controlled trials of a single dose of baclofen (GABA-B agonist) and a 2-week daily regimen of BAER-101 (alpha-2,3-selective GABA-A agonist) in people with FXS.

Methods:Using a Luminex-based system, we obtained peripheral blood levels of FMRP in subjects with FXS who participated in two Phase Ib studies targeting adolescents and adults with FXS. We then analyzed the results of each study using the molecular level of FMRP as a quantitative means for subgroups of patients. The first study was a double-blind, placebo-controlled, crossover, single-dose study of acamprosate, lovastatin, minocycline, and baclofen in adolescents and adults with FXS. The second study of a 2-week, double-blind, placebo-controlled crossover treatment period with the selective GABA-A alpha-2,3 agonist BAER-101 in adults with FXS. Both studies included performance-based outcome measures such as eye tracking, memory tests, and computer-based tests. Each project also focused on specific EEG outcomes, and both studies used high-density EEG scans before and after treatment.

Results:In our single-dose challenge study, acamprosate, minocycline, and lovastatin dosing were not associated with consistent changes in EEG signaling. In 17 adolescents and adults (11 males and 6 females; mean age 26.3 years; range 16-43 years), baclofen (30 mg single dose) was associated with a significant reduction in band frequency EEG activity . Elevated gamma-band activity is a well-known pathological feature of the EEG associated with FXS. In an FMRP-based subgroup analysis, men diagnosed by Southern blot and PCR with the complete and fully methylated FMR1 mutation, but expressing trace amounts of FMRP in their blood, showed a significant reduction in gamma band activity, which was associated with an improvement in social gaze on a tracking measure correlated with eyes. This positive association between EEG and clinical change was found in women or men who did not express FMRP in their blood. Overall, a significant association was found between FMRP levels and EEG gamma band shift, with lower FMRP levels associated with a greater reduction (rescue) in gamma band activity. In our study of BAER-101 in 13 adults with FXS, the low-dose drug (5 mg BID) was associated with improvements in memory, as measured by the Neuropsychiatric State Repeated Battery (RBANS), in men only. No significant BAER-101-associated improvement in EEG measurements was detected in any of the patients. Our FMRP-based subgroup analysis found that men who did not express FMRP in their blood exhibited an improvement in social isolation associated with low doses of BAER-101, as measured by the Aberrant Behavior Checklist (ABC), a shift in the opposite direction compared to to men, expressing some FMRP. Furthermore, this male subgroup with zero FMRP showed a relevant correlation between change in gamma band performance and improvement in memory, with reduction in gamma band being associated with greater improvement in memory as measured by RBANS.

Conclusions:We found early evidence that FMRP status in fragile X syndrome (FXS) may represent a molecular continuum measure of a disease/disorder that affects response to small molecule treatment. The ability to effectively identify molecular subsets of patients based on peripheral FMRP analysis holds promise for use in larger Phase II and III studies to match patient populations with specific investigational drugs. We believe that FMRP levels will support future studies of small molecules in FXS and potentially enable approaches to personalized medicine in this area. We need to collect data from larger patient populations to potentially confirm our initial findings that baclofen use is associated with a stronger positive signal in men expressing minimal levels of FMRP and that BAER-101 use with a positive signal in men that do not express FMRP.

Key words:Fragile X Syndrome, clinical trial methodology, EEG

Divulgaciones: Forge Therapeutics, Impel, Scioto Bioscience, Stalicla: consultor (auto)

Matthew Birnie*, Annabel K. Short, Gregory de Carvalho, Benjamin G. Gunn, Aidan L. Pham, Christy A. Itoga, Xiangmin Xu, Lulu Y. Chen, Stephen V. Mahler, Yuncai Chen, Tallie Z. Baram

University of California-Irvine, Irvine, California, USA

Background:Disrupted reward circuitry is believed to underlie a number of emotional disorders, including depression and substance abuse, disorders that often follow stress in early life. However, it remains unclear how early life adversity (ALS) affects the functional maturation of reward circuits to promote disease. An important component of the reward circuit, the nucleus accumbens (NAc) is a key structure that mediates pleasure, motivation, and emotional processes. Multiple inputs converge on the NAc to modulate reward behavior, including the basolateral amygdala (BLA). The BLA mediates associative learning to aversive and palatable stimuli, and stimulation of glutamatergic projections from the BLA to the NAc promotes palatable behaviors. Here we identify a novel projection that expresses the stress neuropeptide corticotropin-releasing hormone (CRH) to connect the basolateral amygdala (BLA) and nucleus accumbens (NAc). In the NAc, CRH+ axon terminals modulate motivational and reward behavior. Here we identify the role of this CRH+BLA-NAc projection during reward in naïve and ALS mice.

Methods:By combining viral genetic approaches with CRH-IRES-Cre mice and Cre-dependent viruses, we identified CRH+BLA projections to the NAc. To determine the function of this new CRH+BLA-NAc projection, we used chemo, optogenetic and electrophysiological strategies in control (CTL) and ALS mice. In these mice, excitatory or inhibitory Cre-dependent DREADD and optogenetic viruses were injected into BLA, followed by targeted microinjections of CNO or light activation into the medial envelope of NAc. Behaviorally, we tested the functioning of this pathway with rewarding and non-rewarding tasks.

Results:Male ALS mice have a reduced preference for sucrose, palatable food and sex signal compared to CTL. Viral genetic monitoring combined with electrophysiology identified a novel GABAergic projection that co-expresses the stress neuropeptide CRH from the BLA to the medial envelope of the NAc. In free-ranging mice, stimulating this projection with chemo and optogenetic techniques reduced preferences for sucrose, tasty food, and a sexual cue, but did not alter non-reward related tasks. In adult ALS mice, chemogenetic inhibition of CRH+BLA-NAc GABAergic projection rescued this reward behavior.

Conclusions:Here we identify a new CRH + BLA-NAc GABAergic projection and establish its role in mediating the effects of stress on reward behavior. These findings offer potential selective targets for prevention and intervention in conduct disorders that accompany multiple psychopathologies.

Key words:Basolateral amygdala, nucleus accumbens, CRH, early life stress, GABA

To disclose:Nothing to disclose.

Matthew Mosconi*, Erin K. Bojanek, Shannon Kelly, Lauren Schmitt, Stormi P. White, John Sweeney

University of Kansas, Lawrence, Kansas, USA. UU.

Background:Sensorimotor deficits, including reduced feedback and motor behavior control, are common in autism spectrum disorders (ASD) and have been documented in unaffected first-degree relatives. These results suggest that sensorimotor traits may serve as useful endophenotypes for understanding the hereditary risk pathways associated with ASDs. To determine the extent to which sensorimotor traits were familial in ASDs, sensorimotor behaviors were examined in a cohort of family triads that included individuals with ASDs (probands) and each of their biological parents. We also tested several separate motor behaviors (fast and sustained) in various effector systems (hand and eye).

Methods:Fifty-eight ASD subjects (subjects; ages 5 to 17 years), 109 parents (ASD parents; ages 29 to 54 years), and 89 neurotypical control (NT) participants matched for age, gender, and nonverbal IQ . they completed the manual and oculomotor skills exams. To assess progress control processes, participants completed precision rapid grip (hand motor) and visually guided saccade (VGS; oculomotor) tests. During the quick grip test, participants viewed a static red/green target bar and were instructed to squeeze the load cells as quickly as possible when the red target bar turned green such that a white force bar reached the level of the green target bar set. at 15, 45 or 75% of its maximum power. The accuracy of the initial force output was examined. During the VGS test, participants fixed a central cross and performed reactive saccades that suddenly appeared as peripheral targets at +12 or 24 degrees. The accuracy of saccadic movements was examined. To assess sensory feedback control of motor behavior, participants completed tests of sustained precision (manual) and smooth tracking eye movements (oculomotor). The endurance grip test was similar to the speed grip test, but participants were instructed to maintain constant force at the height of the target bar for 8 seconds. Sustained variability in grip strength was examined. During the smooth tracking test, participants tracked targets moving from 0 to +15 degrees at different speeds (2-30 degrees/sec). Track smooth gain, or the relationship between track speed and target speed, was examined. We also performed subgroup analyzes comparing families with at least one parent exhibiting broader phenotypic autism traits (BAP+) and those with two parents without BAP traits (BAP-).

Results:During the VGS and rapid accuracy tests, subjects had reduced accuracy compared to NT controls. These differences were specific to individuals with BAP parents. BAP parents also showed reduced saccade accuracy compared to BAP+ parents and NT controls. Saccadic precision was intertwined among familiar trios. During eye movement tests with sustained precision grip and smooth tracking, subjects showed performance deficiencies compared to NT controls, including increased variability during grip and decreased reinforcement during smooth tracking. Greater strength variability was more pronounced in individuals with BAP+ parents than in individuals with BAP parents. BAP parents showed greater variability in precision grip strength compared to BAP+ parents and controls.

Conclusions:Findings that rapid sensorimotor behaviors are selectively influenced in individuals with BAP and parents suggest that they may reflect polygenic impairments independent of familial autistic traits. Persistent sensorimotor behaviors were affected in BAP+ individuals and BAP parents, implying overlapping or additive polygenic risk with core features of autism. These results are consistent with previous research suggesting that sensorimotor impairments may serve as useful quantitative endophenotypes, reflecting inherited polygenic risk for ASD. The results also indicate that separate sensorimotor behaviors associated with different neurophysiological processes may represent unique pathways of familial ASD risk.

Key words:Autism, sensorimotor function, endophenotypes

To disclose:Nothing to disclose.

Yi-Ling Chien*, Susan Shur-Fen Gau

National Taiwan University Hospital, Taipeh, Taiwan (Republic of China)

Background:Abnormal cortical anatomy is one of the significant features of neuropathology in autism spectrum disorders (ASD). Several cortical regions were identified as altered in individuals with ASD. However, it is not conclusive which cortical index can be correlated with the clinical severity of autistic symptoms. This study aims to identify the cortical components that best explain the overall severity of ASDs.

Methods:We recruited 122 patients with ASD and 118 controls (DC) with normal development. All participants underwent brain MRI. Cortical thickness was analyzed using the FreeSurfer software with 74 automatic subdivisions. The severity of autistic symptoms was measured using the Social Response Scale (SRS), the Social Communication Questionnaire (SCQ) and the Autism Spectrum Quotient (AQ). We performed principal component analysis of cortical thickness and volume of the cerebral cortex to identify principal components of cortical indices and examined their correlations with the severity of autistic symptoms.

Results:In principal component analysis, there were 9 components for white matter volume, 3 for cortical volume, and 6 for cortical thickness. To correlate these factors with autistic traits, we found that none of the 9 white matter components correlated significantly with total AQ or SRS scores. For the cortical volume components, we found that the second component was correlated with AQ and SRS totals. Correlation coefficients were 0.27 for total AQ scores, 0.37 for total SRS scores. Both are low-level correlations. Regarding the cortical thickness component, the first three components were correlated with the overall AQ scores. Correlation coefficients ranged from 0.28 to 0.45, with the highest correlation in factor 3. For SRS, factors 2, 3, 4 were correlated with total scores, correlation coefficients ranged from 0.24 to 0 .34, with the highest correlation also in factor 3. The top is the third component in the mean correlation level.

We examined additional cortical thickness parameters to see if they could be better correlated with ASD severity. We adopted the other two cortical subdivisions instead of FreeSurfer. Using a network of 7 constructed based on the intrinsic functional connectivity proposed by Yeo, factors 1 and 3 were correlated with AQ and SRS, the correlation coefficients reached 0.39, slightly lower than those of DKT40- Cortical Thickness Components reaching 0 .45. Finally, regarding the main components of BA, the first two factors were correlated with AQ and SRS. Correlations between factor 1 and AQ or SRS can reach 0.7.

Conclusions:This study found that an important component of cortical thickness is significantly correlated with the severity of autistic symptoms. Autistic severity is associated with major components of cortical thickness and volume, but not with white matter volume. Autistic severity is also linked to core components based on functional connectivity. The highest correlations were in the sensory and motor components of the BA area. Our results warrant further validation.

Key words:Autism, cerebral cortex, core symptoms of ASD

To disclose:Nothing to disclose.

Robert McNamara, Alexis Brown, Maxwell Tallman, Thomas Blom, Jeffrey Welge, Jenni Farrow, L. Rodrigo Patiño, Melissa DelBello*

University of Cincinnati, Cincinnati, Ohio, USA. UU.

Background:The initial onset of Bipolar I Disorder (BD) usually occurs during the peripubertal period and is often preceded by Attention Deficit Hyperactivity Disorder (ADHD). Prospective studies have shown that ADHD increases the risk of developing mood disorders, including BD, and is associated with a younger age of onset of mood symptoms. However, the vulnerability factors associated with the risk of developing TB in adolescents with ADHD remain poorly understood. Having a first-degree relative with TB significantly increases the risk of TB in offspring, and adolescents with a first-degree relative with TB have higher rates of ADHD and more severe ADHD symptoms. Furthermore, retrospective studies suggest that prior exposure to stimulants may trigger or exacerbate manic symptoms and accelerate the onset of mania in a subset of people. Finally, BD juveniles are deficient in omega-3 polyunsaturated fatty acids (n-3 PUFAs), including docosahexaenoic acid (DHA), and developmental DHA insufficiency in rodents impairs dopamine neurotransmission and the stress response. To examine these potential risk factors, this study compared the effects of 12 weeks of psychostimulant treatment in adolescents with ADHD (“high risk”, HR) and without (“low risk”, LR) a first-degree relative with TB. We hypothesized that, compared to LR adolescents, HR adolescents would exhibit a greater increase in symptoms previously found to precede and predict the initial onset of BD, including manic symptoms and self-reported assessments of dysregulation. PUFA biostatus correlated negatively with these changes.

Methods:Adolescents with ADHD (10-18 years old) with (“high risk”, HR) and without (“low risk”, LR) a first-degree relative with TB were included. LR teens received mixed extended-release amphetamine salts (MAS-XR) for 12 weeks, and HR teens were randomized to MAS-XR or placebo (PBO). All patients with ADHD met DSM-5 criteria for ADHD (of any type), had not been exposed to psychostimulants for at least 3 months prior to enrollment, and did not have comorbid mood, behavioral, or eating disorders, or psychotic ADHD Clinical Assessments (ADHD Rating Scale, ADHD-RS), Mania (Youth Mania Rating Scale, YMRS), Depression (Revised Childhood Depression Rating Scale, CDRS-R), Global Functioning (Children's Global Rating Scale, CGAS) and Global Symptom Severity (Clinical Global Impression Severity Scale, CGI-S) were performed and parents completed the Child Behavior Checklist (CBCL) at baseline and at week 12. [EPA] levels +DHA, arachidonic acid, AA) were determined by gas chromatography. Group x time interactions in baseline endpoint change scores were calculated and correlations were made between al scores. symptom response and reference fatty acid levels.

Results:A total of n = 96 (HR: n = 47; LR: n = 49) adolescents with ADHD (mean age: 13.9 ± 2.5 years) (LR-MAS: n = 49; HR-MAS: n = )31. HR-PBO: n = 16). There were no significant differences between the reference groups in terms of age, sex, race, pubertal status, body mass index or previous exposure to psychostimulants. The HR-MAS group had lower baseline levels of DHA (p = 0.01) and EPA + DHA (p = 0.007) but not AA (p = 0) compared to LR-MAS but not HR-PBO 0 ,91). After 12 weeks of treatment with MAS-XR (mean MAS-XR dose: LR: 17.7 ± 5.2 vs. HR: 15.8 ± 5.7, p = 0.12), the LR-MAS had a significantly greater reduction in total ADHD-RS scores (p=0.12). 0.015) and inattention subscale scores (p = 0.0001) compared with HR-MAS. A greater percentage of LR-MAS achieved remission (ADHD-RS endpoint score <18) compared with HR-MAS (92% vs. 61%, p = 0.0001). LR-MAS adolescents also showed significantly greater improvements in overall illness severity (CGI-S, p = 0.0001) and global functioning (CGAS, p = 0.0008) compared with HR-MAS, and there was a trend for a greater reduction in the CBCL profile dysregulation subscale score (p = 0.08). For all ratings, there was no significant difference in change in endpoints from baseline in the HR-MAS versus HR-PBO groups, and no significant difference between groups in changes in YMRS and CDRS total scores. In all ADHD patients (n = 96), higher baseline RBC-DHA levels were associated with greater improvements in global functioning scores (p = 0.04), and higher AA scores were associated with greater reductions in depression (p = 0.02) and CBCL total score (p = 0.02) and externalization (p = 0.03), internalization (p = 0.04) and dysregulation (p = 0.01) subscales of CBCL. In the HR-MAS and LR-MAS groups, AA levels were different with changes in CGI-S (group interaction, p = 0.028), ADHD-RS total score (p = 0.040) and ADHD-RS subscale score . RS associated with hyperactivity/impulsivity (p = 0.02).

Conclusions:After 12 weeks of treatment with MAS-XR, adolescents with ADHD without a family history of TB show greater reductions in inattentive symptoms and greater improvements in overall illness severity and global functioning compared with adolescents with ADHD and a family history of TB. ADHD adolescents with a family history of BD had lower DHA biostatus compared to ADHD adolescents without a family history of BD, and both DHA and AA were associated with distinct changes in symptoms. These results suggest that ADHD adolescents with a family history of TB may need alternative or complementary treatments for inattention and global functioning, and the associations of PUFA with symptom changes warrant further investigation.

Key words:Bipolar Disorder, ADHD, Psychostimulants, Prodrome

Divulgações: Myriad, Medscape: Advisory Board (auto), Alkermes, Janssen: Consultants (auto), Alkermes, Lundbeck, Janssen, Allergan, Shire: Contract Research (auto),

Angela Tseng, Amy Yang, Bobbi Rohwer, Jason Wolff, Jed Ellison, Suma Jacob*

University of Minnesota, Minneapolis, Minnesota, USA. UU.

Background:Delays in language development are one of the first features associated with autism spectrum disorders (ASD) (Tager-Flusberg, 2016); Observations of atypical communication skills often serve as a stimulus for parents to seek assessments of their children's neurodevelopment (Richards et al., 2016). Autistic children pronounce their first words and phrases later than their peers (Roemer et al., 2019, Charman et al., 2003), and delays in nonverbal communication (e.g., gestures) are associated with deficits in verbal communication, even before language development. (Colgan et al., 2006, Luyster et al., 2008, Mitchell et al., 2006). Furthermore, receptive and expressive language skills are negatively associated with restricted and repetitive behavior in autistic (Ray-Subramanian & Ellis Weismer, 2012) and neurotypical (NT) (Larkin et al., 2017) children, with improvements in language skills. language a determining factor. predict the reduction of symptoms. However, little is known about the role of early verbal and non-verbal language development in sensorimotor and communication pathways in ASD and TN samples.

In the present analysis, we first use the MacArthur Bates Communication Development Inventory (MB-CDI): Words and Gestures (Infant Form) (Fenson et al., 1994) to delineate profiles of early communication based on data in a community sample. 🇧🇷 The MB-CDI Infant Form is a widely used and validated measure designed and standardized for use with children 8 to 18 months of age and older with developmental delay; Caregivers are asked to rate their child's ability in various components of language development, including raw scores and percentage rankings for expressive (produced words; WP) and receptive (understood words; WU, sentences) language. the use of the Child results from actions and gestures (Total Gestures; GT). In an effort to explore the informational potential of these new profiles, we examined associations between these groups using data collected concurrently with the Video-Referenced Reciprocal Social Behavior Rating (vrRSB; 18- to 30-month version), a self-report measure. parents, has high reliability in quantifying autistic traits in community samples (Marrus et al., 2018, Marrus et al., 2015, Marrus et al., 2020) and the Repetitive Behavior Scales - Early Childhood Supplement ( RBS-EC) (Wolff et al., 2016, Sifre et al., 2021), a measure of parental reporting of restrictive and repetitive behavior in children (8 months to 8 years).

Methods:Survey measures (MB-CDI: WG, vrRSB, RBS-EC, demographic data) were completed online by parents of N = 904 (47.9% female), community-identified children (mean age = 18 0, 08 ± 0.53 months) during the initial phase a larger, descriptive and longitudinal study was carried out. Using a two-stage cluster analysis (TSC) based on data with MB-CDI percentile ranks (WP, WU, PhU, TG), we use a logarithmic probability distance measure, the information criteria clustering criterion of Akaike (AIC) and a maximum of 15 bunches. To derive sparse profile TSC clusters, silhouette cohesion and separation coefficients together with membership variables of each cluster solution were used. Various general linear models (GLMs) were used to examine associations between TSC groups derived from MB-CDI, sex, age, vrRSB, and RBS-EC data.

Results:TSC analysis with percentage ranks for TG/WP variables yielded a four-group solution with a good measure of cohesion silhouette and separation coefficient (0.62): 1. LowWP/LowTG (N = 390); 2. High WP/Low TG (N = 139); 3. Low PC/high TG (N = 243); 4. High WP/High TG (N = 132). A similar four-cluster solution was found for WU/WP in the good cluster quality range (coefficient = 0.56): 1. LowWU/LowWP (N = 354); 2. Low UT/high WP (N = 233); 3. High UT/Low WP (N = 170); 4. High UT/high WP (N = 147). The TSC analysis with PhU only returned a solution of three groups (coefficient = 0.74): 1. LowPhU (N = 385); 2. MidPhU (N=362); AltoPhu (N = 157).

Covarying by age, GLM analyzes revealed discriminatory groupings by profile group membership and gender for ASD traits on the vrRSB subscale and composite scores (p < 0.01), as well as mean frequency and interference subscale and composite scores on RBS- CE (p < 0.05). In general, groups with lower MB-CDI percentile scores on all included variables (e.g., LowWP/LowTG, LowWU/LowWP) are associated with higher vrRSB and RBS-EC scores (i.e., higher risk of TEA). However, clustering also suggested different profiles for people who showed asymmetrical development of verbal and non-verbal communication skills (eg, LowWP/HighTG, HighWU/LowWP), which could provide more information about heterogeneity.

Conclusions:New TEA functions. Of particular interest is that siblings of autistic children at increased risk of an ASD diagnosis (18.7% relapse rate) show significant variability in language and gesture development (Ozonoff et al., 2011, Iverson et al., 2018), suggesting that associations between expressive and receptive verbal skills and gestures should be explored in the general population to capture heterogeneity in communicative development. Our community sample data will inform efforts to characterize early markers of ASD and focus on early therapeutic targets for personalized interventions.

Key words:Autism, communication, speech delay, cluster analysis, community screening

To disclose:Nothing to disclose.

Sonja Stojanovski, Guido Guberman, Eman Nishat, Jean-Christophe Houde, Maxime Descoteaux, Anne Wheeler*

SickKids Research Institute, Toronto, Canada

Background:Attention problems are common in children after a concussion. The short fibers of superficial white matter (SWM) in the brain are particularly susceptible to concussions in children because of their long-term myelination and location at the subcortical interface of gray and white matter. The objectives of this study are to describe changes in SWM in children with concussion and their impact on care and the structure of the community network.

Methods:9- to 10-year-old boys and girls with concussion (N = 339) were matched with children without concussion (N = 339) from the Adolescent Brain Cognitive Development Study. Particle filter tractography was applied to multilayer diffusion MRI data to generate weighted matrices with four model tensor measurements (FA, MD, AD, RD) and two of the fiber orientation distribution functions obtained from Constrained Spherical Deconvolution (AFD, NuFO). SWM was derived using length thresholds (<85 mm), while local community measures (modularity, mean clustering coefficient) were calculated from full matrices. Attention was assessed using the CBCL Attention Problems Scale. Differences between concussion and control groups and the relationship between measures were assessed using linear mixed-effects models.

Results:Children with concussion had more clinically significant scores for attention problems (p=4.9x10-6). Children with concussion had higher FA, MD, RD, AFD and NuFO (ps<2.0x10-8), lower AD (p=2.0x10-16) in SWM and lower network modularity (p=2.0x10- 16) and mean clustering coefficient (p = 2.0x10-16) compared to controls. Interactions between SWM measures and age showed that, in younger children with concussion, impaired SWM measures were associated with more attention problems.

Conclusions:SWM fiber maturation and LAN structure can be changed by concussion and affect attention.

Key words:Concussion, alertness, diffusion MRI, brain networks, white matter microstructure

To disclose:Nothing to disclose.

Jason Smucny*, Linhao Chen, Hiroshi Sakakibara, Soumil Shekdar, Ruyi Yang, Ian Davidson, Cameron Carter

University of California – Davis, Sacramento, California, USA

Background:Early detection of children with behavioral and psychopathological problems is essential for both clinicians and families. While predictive modeling methods such as machine learning (ML) have been used to identify predictors, most of this work to date has been cross-sectional, i.e. using baseline predictors to predict baseline symptoms. . Here, we use a multimodal ensemble machine learning approach explainable using a large dataset (the Adolescent Brain and Cognitive Development (ABCD) Study) in which we use benchmark features to assess the occurrence of "persistent" (vs. "absent/sender" ). to predict ) Child Behavior Checklist (CBCL) Scale scores (anxious/depressed, withdrawn/depressed, somatic complaints, social problems, thinking problems, attention problems, behavior against rules, aggressive behavior, internalizing, externalizing, problems general) to two years ascension follow-up period.

Methods:Demographic, environmental, neurocognitive, and brain imaging data were trained on separate neural network-based models and combined into a ensemble to generate sustained CBCL scores (defined as a t CBCL score of ≥ 65 at at least two time points). (baseline /one).(two years follow-up/two years) vs. absence/remission (defined as a CBCL t-score ≥ 64 at at least two time points) Neuroimaging features were downgraded by component analysis (PCA) prior to enrollment with independent PCA performed for each modality (volume structure MRI , diffusion tensor imaging, resting state fMRI, task fMRI for each contrast of interest. Location was also included as a predictor. As the sample was highly skewed (~95% were absent/in remission for all scales CBCL) the minority class (Persistent) was oversampled and the class weights were modified. loss function to avoid an incorrect prediction of the Minder heitsklasse led to a greater loss. Learning performance was validated by k-fold cross-validation. Explainable artificial intelligence (XAI) integrated gradient analysis was used to identify key predictors.

Results:From a sample size of 7902 with complete data, 378 were defined as persistent and 7524 as absent/medium remitting using the CBCL scores. Mean model accuracy across all scales was 79% (95% CI 78-80%), including 83% accuracy (95% CI 82-84%) for "general problems", 83% accuracy for the score broadband outsourcing score (95% CI 81%-85%) and 74% accuracy for the broadband outsourcing score (95% CI 73%-75%). Prediction accuracy for 2-year courses of certain syndromes ranged from 70% (for somatic complaints) to 90% (for rule violations). The XAI suggested that reasoning scores on the WISC-V battery, the School Protective Factors and Risk Questionnaire, School Participation and Environment scores, household income, and sleep problems were the top five predictors of syndrome progression.

Conclusions:These results suggest that machine learning can use baseline data to predict 2-year trajectories of CBCL scores in children. Cognitive thinking, school problems, family income, and sleep problems can be particularly effective predictors of clinically meaningful outcomes.

Key words:Developmental psychopathology, machine learning, explainable AI, ABCD study, sleep disorders

To disclose:Nothing to disclose.

Alexander Weigard*, Mike Angstadt, Aman Taxali, Zvi Shapiro, Mary Heitzeg, Chandra Sripada

University of Michigan Medical Center, Ann Arbor, Michigan, USA

Background:Evidence accumulation efficiency (EAE), a cognitive mechanism formally defined in computational models that drives people's cognitive performance in many contexts, has recently been found to be impaired in several psychopathologies, most notably attention-deficit/hyperactivity disorder (ADHD) in childhood. 🇧🇷 Although new evidence suggests that the EEA may be supported by the frontoparietal network and related neural systems that respond to external task demands, there is currently a dearth of research testing whether the EEA has plausible relationships between the functioning of these neural systems and transmitted psychopathology. In the Adolescent Brain Cognitive Development (ABCD) study sample, we examined relationships between individual differences in neural responses to cognitive demands in the n-back task, which is known to engage frontoparietal networks and other positive tasks while suppressing networks associated with Off . -task processing (eg networking in standard mode) and the EEE of individuals. We then assessed whether EEA is a potential mediator of the relationship between neural responses to cognitive demands and ADHD symptoms, as measured by parent and teacher reports one year later.

Methods:We focused on a subsample of adolescents from ABCD Release 4.0 (n = 2347) who had 1) baseline n-back neuroimaging data that passed quality checks and 2) valid parent-teacher reports of ADHD symptoms in the year they had -1 follow-up visit. EEA was measured using Diffusion Decision Modeling (DDM) on data from the n-back task and data from a separate task completed in the neuroimaging session, the stop sign paradigm ('Go' trials only). A Bayesian estimate was measured within the dynamic models of the Wahl R ensemble. We constructed multivariate "expression scores" for subjects' neural responses to cognitive demands by performing voxel parameter estimates for group-level contrast of 2 backs versus 0 backs, solidly activating positive task networks and disabling negative task networks and multiplying these estimates by the voxel parameters of each individual for the same contrast. Therefore, higher values ​​of such scores indicate that an individual is showing greater expression of the normative pattern of neural responses to cognitive demands. ADHD symptoms were measured dimensionally by fitting a two-factor model to parent-teacher report data from the 1-year follow-up study and estimating values ​​for the common factor, which represents the common variation across informants and the home and home context. school. 🇧🇷 We first tested the bivariate relationships between neuronal expression scores, EAS, and ADHD symptoms. Next, we tested formal mediation models in which the EEA measured the relationship between neuronal expression levels and future ADHD symptoms. All inference models were estimated in MPlus, using pooled bootstrap to estimate standard errors and accounting for nesting of participants within ABCD families and study sites.

Results:Expression scores of neural responses to cognitive demands in the n-back task showed a strong positive relationship with EEA in the same task (standardized Β =0.58, p <0.001) and a lower relationship with EEA in the signal task. stopping (Β = 0.19, p < 0.001). Expression scores were negatively associated with ADHD symptoms (Β=-0.16, p<0.001). EEA was associated with future ADHD symptoms, either in the N-back task (Β=-0.17, p<0.001) or in the stop sign task (Β=-0.16, p<0.001). 🇧🇷 The EEA n-back mediated model showed an effect of EEA expression score (Β = 0.58, p <001), an effect of EEA on future ADHD symptoms (Β = -0.12, p <0.001) and an overall significant EEA-mediated indirect effect (Β = -0.07, p < .001). A direct residual effect of expression score on ADHD symptoms was also demonstrated (Β = -0.09, p = .001). Despite the smaller bivariate relationship between neuronal expression values ​​and the EEA measured by the stop sign task, all of the above relationships remained significant in a second mediation analysis that included the EEA in the stop sign and not the n-back, suggesting that this Effect mediation is not specific to n-back performance.

Conclusions:In a subsample of the ABCD study, we found that neural responses to n-back cognitive demands, reflecting activation of frontoparietal and other task-positive networks and default mode network deactivation, were strongly related to EEA in this task, as well as with broader relationships with the EEA, as measured by a separate stop sign task. Furthermore, we found that EEA partially mediated the relationship between neural responses to cognitive demands and future ADHD symptoms measured through parent and teacher reports, and that this mediation effect was robust when EEA was measured on the same task. than neural responses. These findings establish neural responses to cognitive demands and a central neural correlate of individual differences in ESA in childhood, and provide the first formal evidence of whether ESA plausibly mediates the relationship between neural function and childhood symptoms.

Key words:Attention Deficit Hyperactivity Disorder, Computational Cognitive Neuroscience, Computational Psychiatry, Frontoparietal Network

To disclose:Nothing to disclose.

Victoria Rodríguez, Hayley He, Alexa Soares, Ariana Navar, Joseph Slama, Dionysius Amodeo, M. Margaret Behrens, Susan Powell*

University of California, San Diego, La Jolla, California, USA

Background:Evidence for the role of environmental factors in the development of various neurodevelopmental disorders has accumulated in recent years and increasingly points to a possible interaction between genetic susceptibility and environment in the development of autism and schizophrenia. In fact, epidemiological studies have consistently found that maternal infections and environmental chemicals alone or in conjunction with genetic factors increase the risk of ASD. Animal models of maternal infection have found that maternal immune activation (MIA) is a key factor in the neurodevelopmental changes seen in offspring. In addition to exposure to infectious agents, there is increasing evidence that exposure to environmental toxins may contribute to the risk of ASD. Polychlorinated biphenyls (PCBs, banned since 1976) and polybrominated diphenyl ethers (PBDEs, used as flame retardants) have been accumulating in the environment for decades. Mouse models have shown that exposure to these compounds induces changes in neurodevelopment, leading to changes in synaptic plasticity and behavioral changes. Due to the adverse effects seen in humans and the toxicity seen in animal models, there is growing concern that PBDE chemicals negatively contribute to neurodevelopment. Our previous studies showed that prenatal poly(I:C) exposure impaired probabilistic inversion learning, reduced social focus in the offspring, and had long-term effects on genes involved in glutamine neurotransmission, mTOR signaling, and activity. of the involved potassium ion channel. This study tested whether exposure to PBDE chemicals in flame retardants during pregnancy and in the early prenatal period exacerbates the effects of maternal immune activation on behavioral phenotypes associated with neurodevelopmental disorders.

Methods:After performing a BDE-47 dose-response in a previous trial, we concluded that a dose of 0.03 mg/kg/day of BDE-47 was well tolerated by mothers. Female C57BL6/J mice (8 weeks old; Jackson Lab, Bar Harbor, ME) were mated 4 weeks prior to mating and then throughout gestation until weaning (~10 weeks total). A separate group of female mice received only corn flakes with corn oil. After timed matings, pregnant females were challenged with poly(I:C) (20 mg/kg) or saline at E12.5. Offspring were assessed on a behavioral battery relevant to neurodevelopmental disorders.

Results:In general, the survival rate of the litter in the experiment was low. Effects were most pronounced in litters exposed to BDE, with a litter survival rate of ~35%, compared to litters exposed to vehicle (~58%). Female mice exposed to BDE showed increased locomotor activity compared to mice exposed to vehicle [F(1,46)=5.98, p<0.05], and the effects in the BDE-polyI combined group: C were slightly greater pronounced. There were no differences in locomotor activity in male mice after exposure to BDE or PolyI:C; however, male mice exposed to BDE showed improved reproductive behavior [main effect of BDE; p < 0.05]. When 7-week-old mice were tested on the social approach task, no differences in social behavior were observed. As our previous studies showed that male mice in the MIA model are more sensitive to deficits in social focus, we retested male mice at 6-7 months of age in the social focus task. BDE had no impact on social focus; however, male pups from mothers treated with polyI:C at E12.5 did not spend significantly more time examining the new mouse compared to an empty cup (NS). This resulted in a tendency for the polyI:C carrier mice to show a reduced percentage of time with the foreign mouse. The mice were then tested for sensitivity to amphetamine, a dopamine agonist. Female mice exposed to PolyI:C during pregnancy showed reduced sensitivity to the locomotor effects of amphetamine [main effect of PolyI:C; F(1.37)=4.66, p<0.05], the effect being mainly driven by the polyI:C group of the vehicle [blockage x gestational exposure x polyI:C interaction; F(8.296)=2.30, p < 0.05]. A different pattern of effects was seen in male mice, with male mice exposed to BDE showing reduced sensitivity to amphetamine-induced locomotor activity [p<0.05].

Conclusions:In general, mice exposed to BDE showed sex-specific changes in locomotor activity, scanning behavior, and amphetamine sensitivity. Whereas exposure to PolyI:C during pregnancy resulted in a slight deficit in social focus in male mice and an altered response to amphetamine in female mice. Interestingly, there were no significant interactions between BDE-47 and PolyI:C exposure during pregnancy. A limitation of the study is the low overall survival of the litter.

Key words:Maternal immune system activation, flame retardants, neurodevelopmental disorders

To disclose:Nothing to disclose.

Hellen Weinschutz Mendes*, Tianying Chen, Yunqing Liu, Weimiao Wu, Uma Neelakantan, Ningshan Li, Sumedha Chowdhury, Andrea Gorodezky, Jeffrey Eilbott, Brent Vander Wyk, Zuoheng Wang, Ellen Hoffman

Yale University, New Haven, Connecticut, USA. UU.

Background:Autism spectrum disorders (ASD) are a group of complex neurodevelopmental disorders that affect social behavior and communication and are characterized by the presence of repetitive and restrictive behaviors. Pharmacological interventions targeting central AAS deficiencies are still scarce, mainly due to their complex biology and clinical heterogeneity. Whole exome sequencing revealed "high confidence" risk genes associated with ASD (hcASD), improving our understanding of the biology of ASD. In this context, the zebrafish has become an ideal vertebrate model for genetic studies due to its rapid development, the transparency of its embryos, the availability of efficient methods to generate mutant strains, and its reproducibility for high-throughput analyses.

Methods:Using CRISPR/Cas9 technology, we generated mutant zebrafish lines from ten hcASD genes. To study how genetic disruption alters basic sensory processing and rest-wake activity, we established a new high-throughput in vivo behavioral system that was used for the different hcASD zebrafish mutant strains. Mutant zebrafish larvae are placed 5-7 days after fertilization in a 96-well plate where responses to on-off stimuli and sleep-wake behavior are monitored.

Results:These analyzes generated a unique behavioral fingerprint for each mutant. In parallel, this system was used to examine wild-type zebrafish larvae treated with more than 750 FDA-approved drugs to identify their effects on these behaviors and to identify drug behaviors. By comparing the effect of drug behavioral profiling with mutant behavioral fingerprinting, we were able to identify several dysregulated signaling pathways in mutants and potential suppressors of hcASD behavioral phenotypes. More specifically, using mixed linear model analysis (LMM), we identified key anti-correlational drug compounds for each mutant zebrafish strain. These drugs include compounds representing a variety of mechanisms, including estrogenic compounds, anti-inflammatory drugs, and anticancer drugs. We then challenged mutants with selected anti-correlative compounds to identify suppressors of mutant behavioral phenotypes.

Conclusions:The discovery of pharmacological suppressors of these phenotypes has the potential to identify candidate drugs for further investigation in ASDs.

Key words:Autism, zebrafish, drug discovery: new approaches, high-throughput detection

To disclose:Nothing to disclose.

Tamara Sussman*, Albert Wakhloo, Jonathan Posner, Cristiane S. Duarte

Columbia University Medical Center, New York, New York, United States

Background:Increased exposure to adverse childhood experiences (ACE) is an established risk factor for a variety of adverse mental health outcomes (Dube et al., 2003; Dube et al., 2006; Campbell et al., 2016; Shin et al., 2018 ). 🇧🇷 Hughes et al., 2017; Leza et al., 2021). ACEs have also been associated with changes in brain structure and function (e.g., Teicher et al., 2016; Philips et al., 2014), leading some to theorize that ACE-related mental health risks may be related to ACE: Related neural changes can be caused (Puetz et al., 2015; Edalati et al., 2015).

Consistent with this perspective, some authors have suggested that low or moderate stress at an early age may prepare organisms for future stressful experiences, shaping the brain and behavior to adapt to the environment (Oshri et al, 2020). Indeed, studies in rodents and primates have found that early exposure to stress is associated with greater resilience to new stressors later on (Gapp et al., 2014; Parker et al., 2004; Parker et al., 2004). Research on ACE-related neurodevelopmental disorders has produced results consistent with this view. For example, studies have found lower gray matter volume (GMV) in visual regions of the brain in adults who experienced violence as children and higher GMV in adults who experienced parental verbal abuse (Teicher et al., 2016; Tomoda et al., 2011 ). 🇧🇷 Tomoda et al., 2012).

Results from the current pilot are a first look at a study examining the effects of ACEs on neurodevelopment in children ages 10 to 14 whose families participated in the Boricua Youth Study (BYS) in New York City, New York. BYS is an intergenerational cohort selected from representative Puerto Rican families originally recruited in the South Bronx, New York, and San Juan, Puerto Rico. BYS has been guiding families for over 20 years with a focus on mental health outcomes. Here, in preliminary data, we examined the relationship between ACE exposure and GMV in children from the original BYS cohort using non-negative matrix factoring (NMF), a constrained dimension reduction technique designed to preserve sparse components. In this way, we limit the number of statistical comparisons without compromising the interpretability of our results.

Methods:Sixteen children (10 to 14 years old; 9 female) participated in a study at the New York State Psychiatric Institute, New York, NY. ACEs were measured using the CDC Kaiser scale (Fellitti et al., 1998). All participants underwent magnetic resonance imaging, in which T1-weighted images were acquired. Cortical GMVs were extracted from these data using version 7.2.0 of the FreeSurfer pipeline.

NMF was applied to the resulting cortical GMV data matrix. When applied to brain morphometric data, matrix factoring techniques divide the dataset into a series of components, or groups of brain regions, with a series of specific weights for each component. Then, the data for each subject can be reconstructed by taking a weighted sum of the components. Therefore, subject-specific weights serve as a low-dimensional representation of the original dataset, reducing the number of subsequent statistical tests. NMF imposes a non-negativity constraint on weights and components. This results in scattered components, each concentrated in a few regions of the brain. Therefore, relationships between subject-level component weights and exposures of interest can be more easily interpreted.

Before dimensionality reduction, all volumes were divided by their standard deviation to facilitate the interpretation of the resulting components. The NMF algorithm was initialized using a non-negative double singular value decomposition to promote scarcity and was run with coordinate descent under a Frobenius norm loss using the scikit-learn package until the default numerical tolerance was reached. 16 components were used for this decomposition, allowing for near-perfect data reconstruction while significantly reducing the dimensionality of the data. After NMF, the relationship between GMV data and ACE exposure was examined using a series of linear models. Each model used subject-level ACE to predict the reduced dataset (i.e., weights). These models were customized using the Python Statsmodels version 0.13.2 package.

Results:In this preliminary sample, ACEs ranged from 0 to 2 (mean total ACEs = 1.06, SD = 0.77). A component concentrated primarily around the left supramarginal gyrus, right lateral occipital cortex and bilateral precentral cortex showed a significant positive relationship with ACEs (beta = 1.01, p = 0.043), indicating a positive correlation between increased exposure to ACE and an increase in GMV in these regions.

Conclusions:In these pilot analyzes of preliminary data, we found that ACE exposures were in the low range (0-2 ACEs). Within this lower ACE range, without correcting for multiple comparisons, higher ACE exposure was associated with increased GMV in brain regions including the left supramarginal gyrus, right lateral occipital cortex, and bilateral precentral cortex. As increased GMV in the left supramarginal gyrus in early childhood has been associated with improvements in cognitive control (Berger, 2022), it is possible that ACE-related increases in GMV in this region could be a sign of neurocognitive adaptation to environmental stressors. Future analyzes in a larger sample may further evaluate these results, as well as the associations between GMV and task performance, to determine whether ACE-related structural brain changes are associated with cognitive task performance.

This research was funded by NIDA: K08DA049913

Key words:Adverse childhood experiences (ACE), gray matter morphometry, neurodevelopment

To disclose:Nothing to disclose.

Sara Hess*, Grace George, Justin Russell, Ryan Herringa

University of Wisconsin - Madison, Madison, Wisconsin, United States

Background:A critical aspect of socio-emotional development during childhood is the learning and unlearning of environmental fear associations, many of which arise from observing a parent or caregiver. Although indirect threat extinction mechanisms have been explored in animal and adult models, the neurobiological substrates of this formative learning process during childhood remain largely unexplored.

Methods:In this study, we examined whole-brain activation during indirect diurnal extinctions using 27 parent-child dyads (adolescents aged 10-14 years). To characterize how previously learned threat associations can be modified or erased through parental observation, the dyads completed a threat elimination paradigm in which visual stimulus acquisition exhibits with (CS+) and without (CS+) -) reinforcement partial duration of electrodermal stimulation (ES). During vicarious extinction, juveniles watched a video of their parents directly affected by extinction, during which exposure to CS- and CS +  did not pair with ES (CS + vic). The father completed the behavioral paradigm during the simultaneous recording of the skin conductance response, while the young man completed all phases during the fMRI and the recording of the skin conductance. To estimate specific stimulus patterns in whole-brain activation, scans were preprocessed during indirect extinction training with FMRIPREP and results comparing activation during presentation of CS + vic and CS after size threshold are presented. Finally, parent-child physiologic synchrony was estimated using cross-recurrence quantification analysis (CRQA).

Results:During indirect extinction training, adolescents showed significantly reduced activation in the bilateral posterior insular cortex (pIC) while watching their parents viewing the CS+vic compared to watching their parents viewing the CS- (left, k = 423, pcorr <0.01; right, k = 447, pcorr <0.01). Differential activation in the right pIC during CS + vic was positively correlated with autonomous parent-child synchrony during the task (r = 0.502, p = 0.034). Interestingly, measures of parent-child synchrony were not predictive of pIC activation while CS was observed (r = -0.222, p = 0.374).

Conclusions:These results demonstrate for the first time new biomarkers for the transmission of threat and safety learning in parent-child dyads during a critical period of adolescence and suggest a possible mechanism for this transmission through parent-child autonomic synchrony. Differential activation in bilateral pIC when viewing a parent's exposure to previously learned aversive stimuli provides further support for pIC's crucial role in consolidating extinction memory and may be further involved in unraveling the parental pattern of threat responses to aversive stimuli.

Key words:Functional magnetic resonance imaging (fMRI), parent-child dyads, extinction learning

To disclose:Nothing to disclose.

Kenneth Wengler*, Andrew Goldberg, Seonjoo Lee, Guillermo Horga

Columbia University, New York State Psychiatric Institute, New York, New York, United States

Background:Many neuropsychiatric disorders are believed to have developmental origins because of their typically early onset and significant genetic risk. Therefore, describing the normative developmental trajectories of neuroimaging phenotypes is essential to contextualize neurodevelopmental changes in individuals who develop a neuropsychiatric disorder. One such neuroimaging phenotype is the functional magnetic resonance imaging measure of the resting state intrinsic neural time scale (INT). INT reflects the time window of neural integration and is believed to reflect the strength of recurrent excitation in cortical microcircuits, a balancing excitation-inhibition (E/I) relationship crucial for cognition. We and others have recently reported a reduction in INT in patients with schizophrenia, but it is unclear how these reductions relate to neurodevelopment.

It is important to highlight that E/I is implicated in a variety of neuropsychiatric disorders and that recurrent arousal plays a key role in cognitive functions such as working memory. Persistent activity in higher-order cortical circuits, including the dorsolateral prefrontal cortex, has been considered a key substrate for storing information about delay times in working memory tasks. Synthetic biophysical models of canonical microcircuits, even in their simplest form, can perform working memory tasks and recapitulate primate behavior and electrophysiology. Also consistent with these models is the observation that single-neuron INT is positively correlated with working memory performance, although this has not yet been tested with non-invasive INT measurements in humans.

Here, we use two large-scale neuroimaging studies from the Human Connectome Project (Developmental [HCP-D] and Young Adult [HCP-YA]) to characterize age-related patterns of INT development across the brain and to test the linkage hypothesis. between resting INT states and working memory performance.

Methods:Resting-state fMRI data were collected from two publicly available data sets (n = 1601; 55% female): 1) HCP-D (n = 591, 6–21 years); 2) HCP-YA (n = 1,010, 22–37 years). INT maps were estimated as previously described (Wengler et al., eLife, 2020). Briefly, the autocorrelation function of the fMRI signal was estimated at each gray coordinate and the sum of the autocorrelation coefficients over the initial positive period was calculated. INT maps were plotted using atlas HCP-MMP v1.0 and hemisphere average for a total of 188 plots. INT maps have been harmonized with ComBat. Developmental curves were calculated for each package using general linear models: INT = B0 + B1*age + B2*age^2 + B3*sex + B4*movement. Inflection points were calculated for each package and hierarchical effects were evaluated by correlation; Hierarchical ranking was determined by ranking the INT values ​​of the INT map averaged by the HCP-YA group. The relationship with cognition was assessed in the HCP-YA sample (n = 781, excluding individuals who performed worse on 0 backs than on 2 backs) by partial correlation between N-back performance and mean INT on packs containing significantly higher N-enabled - backtracking task: second-level results for the HCP-YA sample determined 47 previous packets (contrast: 2-backtracking>0-backtracking) -motion control (average frame shift). Permutation tests were used to determine statistical significance and correct for multiple comparisons.

Results:Almost all plots showed significant age effects, characterized by an inverted U-shape with INT increase in early childhood/adolescence and INT decrease in adulthood (age: 180/188 positive effect plots, P < 0.05, P_FWE, permutation = 0.001 age2 : 182/188 negative effect packets, P < 0.05, P_FWE, permutation = 0.001). Breakpoints (INT peaks of adjusted quadratic functions) ranged from approximately age 21 to 36 years and appeared later in higher order brain regions (breakpoint and rank correlation: r = 0.75, P_permutation = 0.001). A sex-stratified analysis showed that women had later turning points than men (mean difference = 4.20 years, t = 18.6, P_permutation = 0.001). Results were robust for motion controls, even in a motion-adapted subgroup (n = 1343) and a subgroup with more stringent motion exclusion criteria (n = 690).

Subjects with better cognitive performance (as indicated by 2-back minus 0-back accuracy in the N-back task) had longer INTs in brain regions activated by the task (r_partial = -0.09, P_permutation = 0.012, i.e. minus the difference between precision 2 backtrack and 0 backtrack). This was driven by individuals with longer INTs who performed better during the 2-back condition that required working memory (r_partial = 0.12, P_permutation = 0.001).

Conclusions:Our results describe age-dependent developmental patterns of INT in prepubertal and postpubertal development and show that almost all brain regions in the studied age group (5-37 years) exhibit an inverted U-shaped pattern. Higher-order brain regions (p. In addition, we showed that subjects with longer INTs, measured at rest, performed better on an N-back task. These results confirm the theoretical association between resting-state temporal integration windows ( i.e., INT) and a subject's ability to retain information in working memory, supporting the potential value of INT for studying disorders of cognitive development in neuropsychiatric disorders.

Key words:Intrinsic neural timescale, brain development, cognition, working memory, MRI

To disclose:Nothing to disclose.

Daniel Uliana*, Anthony Grace

University of Pittsburgh, Pittsburgh, Pennsylvania, USA

Background:Stress is a socioenvironmental risk factor for the development of psychiatric disorders, and the age of exposure can determine the subsequent course. Adversity in early life, such as adolescence, has a significant impact on the development of neuropathological conditions in which women respond to stressors differently than men. Adolescence is a critical period for the maturation of the medial prefrontal cortex (mPFC) and is also when sex differences in PFC structure begin to emerge. Dysfunction of the GABAergic network in the prelimbic portion of the PFC (plPFC) during development increases susceptibility to affective dysregulation in adults. However, the precise neurobiological circuits/mechanisms that contribute to gender differential sensitivity to adolescent stress are understudied. Here we examine the effects of exposure to stress during adolescence on adult susceptibility to anhedonia, impotence, and dopaminergic activity in both sexes.

Methods:Male Sprague-Dawley rats were subjected to a combination of paw shock/restraint stress during puberty (31-40 days after birth). Rats were evaluated for sucrose preference (PD70), learned helplessness (PD72-73; day 1, unavoidable paw shock; escape session on day 2) and single extracellular electrophysiological recording of VTA-DA neurons. (>PD78; four days after LH day 2) tested). An independent group of animals was stressed or not and perfused at PD31, PD41, PD51 and PD75 for subsequent immunohistochemical analysis of the PV/SST content in plPFC. All procedures were performed in accordance with the NIH Guide for the Care and Use of Laboratory Animals and were approved by the Institutional Committee on the Care and Use of Animals at the University of Pittsburgh.

Results:Adolescent stress decreased the preference for sucrose (n=4 in each group, t6=4.41, p<0.05, t-test) and increased the percentage of helpless behaviors only in men (naive 35.71%, 9 helpless, 5 helpless; stress 75%, 4 helpless, 12 helpless, chi-square=30.79, p<0.05). No significant effect with regard to sucrose preference or impotence behavior was found in all groups of women (sucrose preference, n=4 naïve, n=5 stress, t7=0.21, p > 0.05, t-test ; impotence; naive 46.15%, 7 without impotence , 6 impotence, stress 43.75%, 9 without impotence, 7 impotence, chi-square=0.0022, p > 0.05). Furthermore, a reduced number of spontaneously active DA neurons was observed in rats exhibiting helpless behavior in all groups exposed to LH. However, adolescent stress increased the number of DA neurons when rats were not exposed to LH (behavior, F5.37 = 24.29, ANOVA, p < 0.05). This is comparable to data showing that chronic mild stress attenuates the hyperdopaminergic state in MAM rats. Adolescent stress increased LW (n=4 each group, age x condition F2.18=3.85, two-way ANOVA, p<0.05) and SST (n=4 each group, age x condition F2.18=4 ,49) via ANOVA, p < 0.05) expression in plPFC in PD51 in men only.

Conclusions:Our results suggest that stress in adolescence reinforces negative affective behaviors, such as B. Decreased preference for sucrose and increased impotence, along with downregulation of dopaminergic activity in the VTA only in males. Men have higher expression of GABAergic markers PV and SST at PD51. Women are resistant to adolescent stress on all behavioral and physiological markers. Thus, a sex-related predisposition to adverse events in early life that affect plPFC activity may increase susceptibility to mood disorders later in life.

Key words:Adolescence, gender difference, early stress, dopamine, affective behavior

To disclose:Nothing to disclose.

Melina Matthiesen, Carl Junior Steininger, Abdessattar Khlaifia, Maryam Dadabhoy, Unza Mumtaz, Maithe Arruda-Carvalho*

University of Toronto - Scarborough, Toronto, Canada

Background:Social behavior emerges early in development, a time marked by the emergence of neurodevelopmental disorders with social deficits, including autism spectrum disorders (ASDs). Although deficits in social interaction and communication are central to the clinical diagnosis of ASDs, very little is known about their neural correlates at the time of clinical onset of the disorders. The nucleus accumbens (NAc), a brain region highly involved in social behavior, undergoes synaptic, cellular and molecular changes in the first years of life and is particularly affected in mouse models of ASD.

Methods:Male and female C57BL/6J and BTBR T + Itpr3tf/J mice were house bred and tested in a three-chamber social interaction or social memory assay on postnatal day (P) 30 (n = 27, 32). The electrophysiology of sections of median spiny neurons from the nucleus Accumbens was examined at P4, P6, P8, P15, P21 and P30 (n = 10-22 cells/group) as in our previous work (Arruda-Carvalho et al., J Neuroscience 2017). spontaneous excitatory and inhibitory transfer. Daily intraperitoneal injections of rapamycin (0.5 mg/kg) of P4-P8 (n=12.14) or P60-P64 (n=9.10) were administered to BTBR mice tested for social interaction at P30 and P86, respectively .

Results:To investigate an association between NAc maturation and neurodevelopmental deficits in social behavior, we compared age-dependent changes in spontaneous synaptic transmission in midcolumn neurons of the NAc layer between the highly social C57BL/6J and the idiopathic ASD mouse model BTBR T+ Itpr3tf/J showing deficits in social interaction (two-way MR ANOVA, significant effect of camera F1.536, 90.61 = 38.79, p < 0.0001 and camera x rod interaction F2, 118 = 16.71, p < 0.0001). Day after birth (P) 4, P6, P8, P15, P21 and P30. We found changes in spontaneous excitation and inhibition from P4 onwards, indicating a potentially critical phase in NAc maturation that could modulate the effectiveness of interventions targeting NAc-dependent behavior. To test this possibility, we injected BTBR mice either in early life (P4-P8) or in adulthood (P60-P64) with the mTOR1 antagonist rapamycin, a well-established rescue measure for ASD-like behavior. We found that rapamycin treatment rescued social interaction deficits in BTBR mice when injected in infancy (2-way MR ANOVA, significant F2 chamber effect, 48 = 22.42, p < 0.0001 and F2 chamber x treatment interaction, 48 = 9.436, p < 0.0003), but not in adulthood (2-way MR ANOVA, significant F2 camera effect, 34 = 7.904, p = 0.0015).

Conclusions:In this study, we found age-dependent changes in the maturation of spontaneous excitatory and inhibitory transmission within and between strains, with BTBR mice showing a general increase in spontaneous inhibition and a decrease in excitation as early as P4 time points. 🇧🇷 Given the timeline of these changes, we hypothesized that early developmental points may include a critical period for the effectiveness of rescue manipulation, which correlates with better outcomes. Consistently, treatment with rapamycin in childhood, but not in adulthood, reversed deficits in social interaction in BTBR mice. Studying brain regions involved in the pathophysiology of neurodevelopmental disorders at clinically relevant time points may provide new insights into the timing and targets of therapeutic interventions to maximize beneficial outcomes.

Key words:Social and behavioral deficits, Nucleus accumbens, Brain development, Autism spectrum disorder

To disclose:Nothing to disclose.

Edenia Menezes, Fabiula Abreu, Melissa Alldred, Catia Teixeira*

Nathan S. Kline Institute, New York University School of Medicine, Orangeburg, New York, USA.

Background:The brain contains interconnected circuits that are not complete at birth or unchanging throughout life. This neural plasticity is essential for lifelong adaptive functions such as ongoing learning and memory. However, this plasticity, particularly when combined with serious adverse factors during the first few years of life, can impede normal brain development and contribute to the etiology of behavioral deficits and psychiatric disorders. One of the most influential environmental factors in early childhood is parent/guardian education. It is estimated that childhood adversity is responsible for a significant percentage of mental health disorders in adults. In extreme cases of childhood adversity, institutional rearing where infants were deprived of contact with caregivers, cognitive deficits, and dysregulated prefrontal cortex (PFC) function have been observed. In this study, we hypothesize that adversities in early life in the form of maternal separation lead to long-lasting changes in the transcriptome of specific populations of PFC cells, leading to dysregulation of PFC function.

Methods:Here we use a mouse model of maternal separation. Brains were collected from offspring and adults of animals reared normally or separated from the mother (MS). In one set, we performed hashed single-core RNAseq to contrast the PFC transcriptome of these clusters. In a separate cohort, we recorded full voltage cutoff (VSD) dye responses to examine how changes in receptors identified by snRNAseq altered PFC responses.

Results:As expected, using snRNAseq, we observed that changes between ages were much more pronounced than changes between treatments. We also observed that the proportion of oligodendrocytes in adult animals with MS was similar to that of lactating animals. Furthermore, we found that most of the differential gene expression between MS and standard breed animals occurred in interneurons that affect signaling pathways related to GABAergic, glutamatergic, and serotonergic functions. Using VSD, we observed that the responses of MS adults to GABAergic and serotonergic agonists were similar to the responses of normally reared immature animals.

Conclusions:This study suggests that MS results in immature PFC, which may be related to behavioral deficits seen in animals and humans exposed to inadequate care in early childhood.

Key words:RNAseq, prefrontal cortex, early life stress

To disclose:Nothing to disclose.

Sergio Iniguez*, Israel Garcia-Carachure

University of Texas at El Paso, El Paso, Texas, USA

Background:Ketamine is currently used to treat treatment-resistant depression in adolescent patients. However, the potential long-term effects of ketamine exposure during adolescence have not been fully studied. Therefore, we investigated whether repeated concomitant exposure to ketamine and/or psychological stress during adolescence leads to lasting changes in spatial memory in male and female C57BL/6 mice (N = 36; 9 per group, N = 44; 11 per group) .

Methods:Postnatal Day (PD) -35 male and female mice were subjected to indirect defeat stress (VDS; a form of psychological stress) for 10 days with or without exposure to ketamine (20 mg/kg; PD35-44). Once the mice reached adulthood (PD70), spatial memory performance was assessed in separate groups performing a water maze task.

Results:We found that a single prior exposure to ketamine or VDS increased the latency (seconds) to finding the escape platform in adult male mice, but not in female mice, demonstrating that ketamine, like psychological stress, only causes a permanent deterioration of the escape platform. flight in males. spatial memory. However, the history of concomitant use of ketamine and VDS prevented spatial memory impairment in adulthood.

Conclusions:Taken together, our results suggest that ketamine as a prophylactic treatment for mental stress-related disorders in adolescents does not induce long-term changes in spatial memory. However, recreational use of youthful ketamine, as well as a history of psychological stress, leads to a permanent deficit in spatial memory in a male manner.

Key words:(R,S)-ketamine, adolescent, spatial memory

To disclose:Nothing to disclose.

Sameera Abuaish*, Seonjoo Lee, Benjamin Tycko, Frances Champagne, Catherine Monk

Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia

Background:Higher rates of obesity in general are associated worldwide with higher BMI during pregnancy, which is known to affect pregnancy and delivery outcomes. Recent research also suggests that early-in-utero factors associated with maternal obesity may influence individuals' long-term health outcomes, including metabolic and neurobehavioral outcomes that are mediated by underlying molecular imprinting mechanisms. Elevated BMI is also associated with altered stress and autonomic nervous system physiology in people, which may contribute to these findings. Studies suggest that heart rate (HR) measurements in the developing fetus may provide early markers of the programming effects of an altered autonomic nervous system to various maternal environmental stressors and a marker of future neurobehavioral functioning in the infant. The placenta is an integral organ and a key mediator of environmental stress that affects the timing of fetal development and results in long-lasting health effects. Gender effects of maternal obesity have been reported in the literature; however, no studies have examined its sex-specific effects on fetal neurobehavioral outcomes and infant temperament and the underlying differential methylation of placental DNA. In this study, we intend to investigate the influence of pre-gestational maternal BMI on psychological and physiological variables related to stress in pregnant women and on fetal neurodevelopment by measuring fetal heart rate and subsequently infant temperament. In addition, we are investigating the epigenetic alteration of genes in the placenta in response to high pre-pregnancy BMI.

Methods:Pregnant women (n = 176) completed the Perceived Stress Scale (PSS) questionnaire and provided saliva samples at gestational weeks (GA) 12-22, 23-28 and 34-36 and participated in performance evaluation sessions. fetal laboratory in EG 23-28 and 34-36 to obtain maternal and fetal heart rates at baseline and in response to maternal cognitive challenge. Placentas close to the fetal surface were collected at birth and DNA methylation assessed using an Illumina matrix (n = 147). At a visit 4 months after birth (n = 75), mothers completed the Infant Behavior Questionnaire to assess the infant's temperament.

Results:We found no association between BMI and daily salivary cortisol or PSS. However, only women with high BMI had higher HR and lower HR variability both in the time domain and in the frequency domain. These effects were only seen in women pregnant with female and non-male fetuses. In addition, we found a similar gender differential effect of high BMI on fetal HR throughout pregnancy, with female fetuses of women with high BMI having significantly lower HRV in the third trimester. Interestingly, these gender effects continued into childhood, with girls born to high-BMI women reporting lower scores on the temperament orientation/regulation dimension, including calmness. Preliminary differential DNA methylation analysis revealed 4 differentially methylated probes, three of which were on chromosome 12 and one on chromosome 10. Only the tenth chromosome probe was associated with an annotated gene, H2AFY2, and was located at the 5'UTR. This probe was hypomethylated. DMR analysis also revealed a region on chromosome 10 in the H2AFY2 gene that encodes MacroH2A2, a central H2A histone. MacroH2A2 is known to be an epigenetic repressor associated with the inactivation of the X chromosome and transcriptionally repressed regions throughout the genome. Sex-stratified DNA methylation analysis did not reveal a significant association.

Conclusions:Our results indicate that the effects of high pre-pregnancy maternal BMI on maternal HR parameters are only seen in pregnant women, and these effects are reflected in their female fetuses. These gender effects persisted into childhood and were associated with neurobehavioral outcomes related to childhood temperament. A high maternal BMI before pregnancy left a molecular signature in placental DNA, with reduced methylation in the promoter of a gene encoding a histone variant associated with transcriptional repression, potentially affecting the placental transcriptional landscape and fetal development.

Key words:Obesity, gender implications, childhood behavior, DNA methylation, fetal neurobehavior

To disclose:Nothing to disclose.

Shau-Ming Wei*, Madeleine Goldberg, Katherine Cole, Pedro Martinez, Michael Gregory, J. Shane Kippenhan, Zachary Trevorrow, Oriana Myers, Christina Recto, Philip Kohn, Lynnette Nieman, Jack Yanovski, Peter Schmidt, Karen Berman

National Institute of Mental Health, Bethesda, Maryland, USA.

Background:The transition to adolescence involves important physical, social, emotional and cognitive changes associated with a greater propensity for risky behavior and is synchronized with the development of several neuropsychiatric disorders. These pubertal behavioral changes, such as increased impulsivity and risk-taking, have been attributed, at least in part, to the effects of emergent pubertal hormones (adrenal, gonadal, and growth hormones) in reward-associated brain regions, including the prepubertal cortex. front. , ventral striatum, and subcortical limbic regions. However, it has been challenging for experimental approaches to distinguish the neurotrophic effects of adrenal androgens from those of gonadal steroids. Adrenarche, characterized by increased secretion of adrenal androgens, including dehydroepiandrosterone sulfate (DHEAS), is the earliest stage of pubertal development, usually starting between 7 and 8 years of age, preceding gonadarch (d. Here we investigate using a paradigm used fMRI to study the relationships between serum DHEAS concentrations and reward-related brain activation in normally developing healthy boys and girls, carefully documented as prepubertal and therefore prior to a rise in gonadal hormones ( i.e., gonadarchy).

Methods:Ninety normally developing prepubertal children (as determined by clinical physical examination; 37 girls, mean age = 8.6 ± 0.3 years; 53 boys, mean age = 8.6 ± 0.3 years) completed three trials of a modified delay task with monetary incentives on a 3T MRI Scanner. Data were derived from participants' first prepubertal baseline visit in a larger longitudinal study. The reward paradigm included low- and high-probability reward trials with expected levels of reward, as well as control trials with no monetary gain. Serum DHEAS and testosterone samples were analyzed by liquid chromatography tandem mass spectrometry and DHEAS concentrations log-transformed for analysis. Serum estradiol was tested using a chemiluminescent assay. Two separate analyzes of multivariate voxel whole brain models were performed using AFNI 3dMVM to test correlations between DHEAS and activation during reward expectation and activation during reward reception (reward gain). Log-transformed DHEAS was included as a continuous variable, while gender was controlled. Post hoc Spearman correlations were performed on R to determine the direction of the correlation.

Results:Both plasma estradiol and testosterone were present at prepubertal concentrations, and no significant sex differences were observed for age or serum DHEAS (p's > 0.6). Among participants, DHEAS ranged from 0.15 mcg/mL to 1.63 mcg/mL (the DHEAS biochemical threshold for the onset of adrenarche is reported to be ≥ 0.4 mcg/mL). and activation of the right ventromedial prefrontal cortex (vmPFC) (pFDR < 0.05). In contrast, during reward anticipation, negative correlations were observed between log-transformed DHEAS and activations in the bilateral dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex, orbitofrontal cortex, and cauda (pFDR < 0.05).

Conclusions:These neurofunctional/DHEAS relationships were found in prepubertal boys before gonadarchal-related increases in the hormones estradiol and testosterone, suggesting that adrenal androgens are associated with and may influence the function of important neural systems involved in reward processing. Future directions will include longitudinal analyzes to better understand the maturation of these reward-related brain systems, starting with this prepubertal reference sample and then moving through different pubertal stages to uncover the impact of relevant endocrine events (eg, gonadarchy). ) in brain development.

Key words:Adrenarche, puberty, children and adolescents, brain development

To disclose:Nothing to disclose.

Rachel Lean*, Christopher Smyser, Joan Luby, Emily Gerstein, Ashley Nielsen, Deanna Barch, Barbara Warner, Cynthia Rogers

University of Washington in St. Louis St. Louis St. Louis St. Louis, MO St. Louis, Missouri, SIM. UU.

Background:Childhood exposure to adversities in early life (poverty and psychosocial stressors) alters the structural and functional development of the brain in the frontal, parietal, and temporal regions involved in the neural networks of executive functions (EF). Abnormal brain development and problems associated with EF increase the risk of psychiatric disorders, including attention deficit hyperactivity disorder and anxiety disorders. However, it is unknown whether associations between adversities in early life and prenatal brain development begin to alter the onset of EF, which could influence the timing of early preventive interventions. Maternal attunement to infant mental states (Motherly Minded Mind (MMM)) is an aspect of the early care environment that supports physical education and brain connectivity in older children. It is unclear to what extent the MMM buffers the adverse effects of adversity in early life by shaping the neural bases of emerging EFs.

Methods:This longitudinal study focuses on 399 mother-infant dyads sampled for poverty exposure identified by the March of Dimes Research Center at Washington University in St. Louis. During pregnancy, mothers took background measurements that were analyzed with confirmatory factor analysis, resulting in two latent factors: social disadvantage (level of education, health insurance status, income-needs ratio [INR], area of ​​deprivation ratio , food consumption) and psychosocial stress (depressive symptoms, perceived stress, racial discrimination, stressful/traumatic life events). At birth, neonates (56% male, 44% female) underwent resting functional (n=319) and diffuse (n=303) magnetic resonance imaging on a Prisma 3T scanner. The main resting state networks included cingulo-opercular (CO), frontoparietal (FPN), ventral (VAN), dorsal attentional (DAN) and default mode networks (DMN). Major white matter pathways included the cingulate, uncinate, and inferior fronto-occipital fasciculus (IFOF). At the 1-year follow-up, MMM was observed during a parent-child interaction task (n = 232 coded). At age 2 years, the Minnesota Executive Function Scale (MEFS) task was used to assess EF scores (previously assessed n = 125) and the INR was reassessed as a measure of postnatal disadvantage. Prenatal social disadvantage and psychosocial stressors were associated with measures of neonatal brain connectivity using multiple regression adjusted for covariates (age at examination, premature birth [<37 weeks of gestation], sex). Adversity variables, brain connectivity measures, and MMM scores were adjusted to MEFS scores using multiple regression and covariate-adjusted moderation analysis.

Results:Prenatal exposure to social disadvantage was independent of aberrant neonatal network connectivity CO (β=-0.15) and NPV-NPV (β=0.13) and right dorsal cingulate (β=-0.17), cingulate bilateral inferior (β = 0.20 ) and IFOF microstructure (β = 0.17) (all p ≤ 0.03). Psychosocial stress was independently associated with CO-DMN connectivity (β = 0.16, p = 0.007) and left uncinate microstructure (β = 0.14, p = 0.01). Social disadvantage and aberrant connectivity of FPN-CO, IFOF, and cingulum predicted poorer EF at 2 years (all p ≤ .03). Maternal psychosocial stress was not independently associated with EFs. Preterm infants had worse EF scores than full-term infants at 2 years of age (t=1.98, p=0.05), but there was no gender difference in EF (t=0.12, p=0 ,90). At follow-up, MMM at year 1 was positively associated with EF at 2 years (β = 0.24, p = 0.02). Moderation analysis suggested that prenatal INR was associated with worse EF outcomes in the group with lower MMM exposure, whereas this association was reduced in the group with higher MMM exposure (interaction term B = -0.06, p = 03, general model R2 = 0.19). 🇧🇷 Although prenatal and postnatal INR were strongly correlated (r= 0.92, p < 0.001), there was no interaction between postnatal INR and MMM in PE (p= 0.07). Moderation analysis also showed that infants exposed to higher MMM had a stronger relationship between neonatal cingulate connectivity and EF score than infants exposed to lower MMM (interaction term B = -0.4.56, p = 0, 03, general model R2 = 0.28). There was no interaction between MMM and FPN-CO or IFOF connectivity in EF (all p > 0.05).

Conclusions:The integration of multimodal neuroimaging, observational, and behavioral data sheds light on the pathways in which delays in EFs occur in early childhood. Prenatal exposure to poverty and altered brain connectivity in newborns increase the risk of worse EF outcomes. MMM can buffer the effects of exposure to poverty and improve brain-EF relationships, making MMM an important intervention target to support EF brain development.

Key words:Prenatal programming, resting state fMRI, MRI diffusion, executive function

To disclose:Nothing to disclose.

Julie Rosenberg, Jens Richard Jepsen, Parisa Mohammadzadeh, Astrid Sevelsted, Mikkel Sørensen, Rebecca Vinding, Klaus Bønnelykke, Hans Bisgaard, Bjørn Ebdrup*

Center for Neuropsychiatric Research in Schizophrenia, Glostrup Mental Health Center, University of Copenhagen, Glostrup, Denmark

Background:Growing evidence supports that maternal inflammation during pregnancy affects early neurodevelopment; however, evidence of long-term risks for aberrant neurodevelopment is sparse and based on preclinical data and human observational studies.

In the current prospective COPSYCH birth cohort, we examined associations between early inflammation relative to maternal inflammation during pregnancy and clinical psychopathological outcomes in children at 10 years of age. Our aim is to replicate the analyzes using children's inflammatory status at 6 months of age as an independent variable. In addition, clinical findings are confirmed using diffusion-weighted imaging parameters.

Methods:COPSYCH is a translational research alliance between the CNSR (Center for Research in Neuropsychiatric Schizophrenia) and COPSAC (Copenhagen Studies of Childhood Asthma) (ClinicalTrials.gov: NCT00798226 and NCT00856947).

COPSYCH is based on the population-based COPSAC2010 cohort consisting of 700 prospectively observed unselected mother-infant pairs starting at 24 weeks of gestation.

At age 10, children complete a two-day visit that includes a comprehensive neurodevelopmental assessment, including categorical and dimensional assessments of psychopathology (Childhood Schema for Affective Disorders and Schizophrenia (K-SADS) and multiple validated rating scales) and tests neurocognitive tests, as well as a 3 Tesla brain MRI that includes diffusion tensor imaging (DTI) sequences. Longitudinal measurements of the highly sensitive inflammatory marker CRP (HS-CRP) and extensive data on potential confounders were obtained from the COPSAC2010 database.

Logistic regression and multiple linear regression were used to estimate odds ratios (ORs) for psychopathological outcomes. Statistical analyzes were performed using multiple linear regression for continuous outcomes (symptom scores and rating scales). The independent variable, CRP-HS, was transformed into log2 to facilitate interpretation. Logistic regression was used for binary endpoints (ADHD yes/no).

Sample Size: The COPSYCH2010 cohort at baseline, N = 700. The follow-up rate at the current 10-year follow-up was N = 592 (86%). Complete datasets after adjustment: N = 567.

Results were checked for gender-specific interactions and, if any, analyzes were stratified by gender. There was no sex interaction at the diagnostic level, but it was significant for symptom scores and rating scales, suggesting that the hs-CRP effect was dominated by boys (probably due to statistical power). HS-CRP vs. ADHD K-SADS symptom score: estimate 0.40, sexual interaction, p = 0.01. Children: estimate 0.60, p < 0.001. Girls: estimate: 0.16, p = 0.07. The ADHD-RS and CBCL DSM 5 ADHD scale show similar results. Statistical significance was set at p < 0.05. Statistical analyzes were calculated using the R software.

Results:Of the 700 children in the birth cohort, 592 10-year-olds underwent the COPSYCH visit (84.6%). Sixty-five (10.9% achieved a research diagnosis of ADHD (16 girls (25%) and 49 (75%) boys). ADHD diagnosis, OR 1.48 (1.22-1.88), p <0.001 The association was maintained at the level of symptoms and between the validated questionnaires (ADHD-RS and CBCL-DSM5-ADHD scale).

Exploratory analyzes showed that the association was driven by the inattentive type of ADHD (ie, ADD), OR 1.65 (1.24-2.07), p<0.001 vs. conventional ADHD symptomatology that includes hyperactivity, impulsivity and inattention OR 1.23 (0.96-1.59) , p = 0.1.

No significant associations with HS-CRP were found for other neurodevelopmental disorders, including autism spectrum disorder, Tourette's syndrome or tic disorder.

Conclusions:The findings add clinical data to the growing evidence for the importance of prenatal exposures in the early years of life, including maternal inflammation. Identifying inflammation as an important marker will provide a potential target for future awareness and prevention during pregnancy and will ultimately improve neurodevelopmental trajectories in children.

Key words:Maternal inflammation, ADHD, birth cohort

Disclosures: Boehringer Ingelheim: research contract (itself), Lundbeck: fees (itself)

[ PubMed ] [ Cross Ref ] Ziu Zhu, Du Lei, Kun Qin, Maxwell Tallman, L. Rodrigo Patino, John A. Sweeney, Melissa DelBello, Robert McNamara*

University of Cincinnati School of Medicine, Cincinnati, Ohio, USA.

Background:Attention-deficit/hyperactivity disorder (ADHD) often precedes the onset of bipolar I disorder (BD), and prospective studies have found that prodromal ADHD significantly increases the risk of developing mood disorders, including BD. Furthermore, ADHD prevalence rates in adolescents with TB are significantly higher than in the general population, particularly in preadolescent children. Furthermore, having a first-degree relative with TB greatly increases the risk of developing TB, and adolescents with a first-degree relative with TB have higher rates of ADHD and more severe ADHD symptoms. Although these results suggest that ADHD together with familial risk of TB may represent a different, more serious illness that carries an increased risk of developing TB, the associated neuropathogenic mechanisms remain poorly understood. The initial onset of BD usually occurs during the peripubertal period, associated with a linear increase in frontal cortex gray matter expansion and connectivity with subcortical regions involved in emotion regulation. Previous structural MRI studies have observed structural abnormalities of cortical and subcortical gray matter in adolescents with BD or ADHD compared to healthy developing adolescents. However, most of these studies did not control for familial risk of TB, ADHD comorbidity, and/or exposure to psychostimulants. In the present cross-sectional study, we examined regional cortical and subcortical morphometry in non-psychostimulant ADHD adolescents with and without first-degree relatives with BD and a typical course control group. In addition, we evaluated the relationships between morphometry and relevant symptom measures.

Methods:Adolescents with ADHD (ages 10-18 years) with (“high risk”, HR) and without (“low risk”, LR) a first-degree relative with TB and typically developing healthy controls (HC) with no personal history or relatives of DSM-5 Axis I psychiatric disorders. All adolescents with ADHD met the DSM-5 criteria for ADHD (of any type), had not been exposed to psychostimulants for at least 3 months prior to enrollment, and had no comorbidities of mood, behavior, eating, or psychotic disorders. Clinical assessments of ADHD (ADHD Rating Scale, ADHD-RS), mania (Mania Rating Scale for Youth, YMRS), depression (Revised Childhood Depression Rating Scale, CDRS-R), Global Functioning (Reviewed Childhood Depression Rating Scale, Child Global Impression, CGAS) and Global Symptom Severity (Clinical Global Impression Severity Scale, CGI-S) and parents completed the Child Behavior Checklist (CBCL). High resolution T1-weighted 3D images were acquired with a Philips 3.0 T MR scanner. FreeSurfer image analysis was used to obtain measurements of cortical thickness, surface area, and volumes of 14 subcortical structures. Group differences were assessed using a general linear model with age and sex as covariates. Post hoc permutation tests assessed pairwise group differences (corrected FDR p < 0.05). Partial correlations were calculated for measures of symptom severity and any significant structural differences in the LR and HR groups, and interaction effects were tested using linear mixed-effects models with age and sex as covariates (FDR corrected p<0.05 ).

Results:A total of n = 142 adolescents (mean age: 14.16 ± 2.54 years, 35.9% female) (HC, n = 48; low risk, n = 49; high risk, n = 49) were included in the analysis. 🇧🇷 No significant differences were observed between groups for age, sex, manual dexterity or prior exposure to psychostimulants in the ADHD groups. Compared with the LR group, the HR group had higher scores on the hyperactivity/impulsivity subscale of the ADHD-RS (p = 0.03), total scores on the YMRS (p = 0.004), and CGI-S (p = 0.01 ) and higher total score on CBCL (p=0.002) and internalizing (p=0.01), externalizing (p=0.002) and dysregulation (p=0.047) subscale scores. No significant differences were found between the LR and HC groups for subcortical volumes. The HR group had smaller volumes in the bilateral thalamus, caudate nucleus and hippocampus, except for the right caudate, compared with the LR group and the HC group. For the cortical surface, the LR group had a larger right parsopercular compared to the HC group. In contrast, the HR group had smaller left postcentral, bilateral inferior parietal, right precuneus, left temporal pole, right fusiform, and left rostroanterior cingulate cortices, and smaller bilateral lateral orbitofrontal, left anterior superior, and posterior orbitofrontal cortices. central left compared to the HR group. HC Group. , bilateral inferior parietal cortex, right precuneus, left temporal pole, right fusiform and right parahippocampal cortex compared to the LR group. In ADHD LR and HR patients (n = 94), ADHD-RS inattention subscale scores were positively correlated with left lateral orbitofrontal surface area (p < 0.0001) and YMRS total scores were inversely associated with the correlation of the lower left area parietal surface (p < 0.0001) and right precuneus surface (p < 0.0001).

Conclusions:Adolescents with ADHD without psychostimulants with a family history of TB have a more severe clinical profile, including greater manic and dysregulatory symptoms and more extensive cortical and subcortical volume abnormalities, compared with adolescents with ADHD without a family history of TB and healthy adolescents. These results suggest that a family history of ADHD-associated BD is associated with a more widespread disruption of peripubertal neurodevelopmental pathways that distinguishes it from ADHD alone.

Key words:Bipolar disorder, ADHD, brain imaging, prodrome

To disclose:Nothing to disclose.

Priscila Goncalves*, Silvia Martins, Neo Gebru, Stacy Ryan-Pettes, Nicholas Allgaier, Alexandra Potter, Hugh Garavan, Matthew Albaugh, Ardesheer Talati

Columbia University, New York, New York, United States

Background:People with a family history of alcohol or substance use problems (FH+) are at risk for increased use, abuse, and eventual development of alcohol and/or substance use disorders (AUD/SUD). HF +  has also been associated with poor development of prefrontal brain regions, particularly those related to executive functioning (EF) and impulsivity. Lower EF and high impulsivity also clearly contribute to alcohol/substance-related problems and AUD/SUD.6–12 Previous cross-sectional studies have shown that FH+ adolescents have thinner frontal cortices, including aspects of the inferior frontal gyrus (eg, pars triangularis) as well such as the lateral orbital and medial frontal cortex. Children with HF +  (aged 9 to 10 years) had reduced cortical thickness throughout the brain, including thinner cortices in the left precentral and paracentral lobes, and greater surface area in the right precentral lobe compared to children with HF - . Little is known about changes in cortical thickness as a function of FH +  during early adolescence, a critical period for brain maturation. Most studies to date have been cross-sectional and/or have covered broad age groups that do not allow for an adequate focus on early adolescence. Our aim was to investigate the course of frontal cortical thickness in prepubertal children aged 9 to 12 years with positive (FH+) versus negative (FH-) family history of alcohol/substance problems.

Methods:Data from ABCD Data Release 4.0, including structural MRI measurements at two time points (baseline [n = 11,878] and 2-year follow-up [n = 6,571]). FH + (n =2861) was defined as ≥1 biological parents and/or ≥2 biological grandparents with a history of alcohol/substance use problems (e.g., substance problems; arrests/DUI; alcohol/substance has been harmful to health; participated in an alcohol/substance treatment program; provoked arguments or was very drunk). Individuals without parents or grandparents with a history of alcohol/substance use problems were classified as HF- (n = 7,017). Individuals with only one grandparent with alcohol/substance problems with HF (n = 1595) or with missing information from all parents and grandparents (n = 405) were excluded. The primary outcome measure was cortical thickness in 11 frontal regions (mediocaudal frontal, pole frontal, lateral orbital, and medial orbital frontal, paracentral, pars orbitalis, pars opercularis, pars triangularis, precentral, superior frontal, and rostral mediofrontal). Desikan-Killiany cortical subdivision atlas.

Statistical analysis

A linear mixed-effects model was fitted to test associations between HF +  and frontal cortical regions covering all 11 frontal cortical regions in both hemispheres, considering the fixed effects of age, sex, race/ethnicity, parental marital status, family income , prenatal alcohol, drug, and tobacco exposure and total intracranial volume and random effects of family relationships (eg, siblings), MRI, and participant identification as random effects. To examine the extent to which age-related change in cortical thickness was scored by FH, we also added an interaction term for FH, point in time (ie, baseline and 2-year follow-up), and frontal cortical regions. We also performed pairwise comparisons to examine differences in specific frontal cortical regions between FH +  and FH- at each time point. Analyzes were performed in R using the "lme4" and "emmeans" packages.

Results:In this sample, 24.9% of preadolescents were FH+ and 61.2% were FH- (13.9% with only 1 grandparent with FH of alcohol/substance use were not included). FH+ was associated with a more pronounced reduction in frontal thickness at 2 years of follow-up compared to baseline (FH+, β -0.10, p<0.001; FH- β -0.08, p<0.001; total - FH x interaction time, p = 0.003). Given the significant global associations, we next examine thickness measurements in each frontal region separately. Baseline was FH+ (vs. FH-) with reduction of paracentral (β-left -0.11 p=0.001) and precentral (β-left -0.08 p=0.001) and medial frontal orbital cortex thicker (β-left 0.07) associated p = 0.004; β-right 0.05 p = 0.04). At two years of follow-up, FH+ was still associated with thinner paracentral (β-left: -0.14 p<0.001, β-right: -0.08 p=0.008), more precentral (β-left -0 , 11 p<0.001 ), β-right -0.12 p < 0.001), superior frontal (β-left -0.08 p = 0.01) and rostral middle frontal cortex (β-left -0.07 p = 0.02) and thicker frontal pole (β-right 0.06 p = 0.04). 🇧🇷

Conclusions:Although previous studies have documented cross-sectional associations between brain structure and FH in alcohol or substance use problems, preliminary results from the present longitudinal study indicate that FH +  is associated with altered development of cortical thickness in frontal areas (particularly in frontal areas). pre and paracentral regions). regions). In particular, when comparing adolescents with HF +  and HF-, HF +  showed differences in frontal cortical thickness at 9-10 years of age. Furthermore, these differences in cortical structure increased in magnitude during early adolescence (ages 11 to 12 years), a time when structural changes in other regions (including areas involved in emotion regulation, such as the upper and midfrontal cortex) change. Future research may investigate dose-dependent (ie, number of relatives) and substance-specific effects of FH+ on adolescent brain development.

Key words:Study of cognitive development of the adolescent brain, cortical development, cortical thickness

To disclose:Nothing to disclose.

Deniz Doruk Camsari, Molly McVoy, Can Ozger, Farhad Kaffashi, Ken Loparo, Farren Briggs, Charles Lewis, Ayse Irem Sonmez, Parmis Fatih, Deniz Yuruk, Julia Shekunov, Jennifer Vande Voort, Paul Croarkin*

Mayo Clinic, Rochester, Minnesota, USA. UU.

Background:Several studies have attempted to characterize suicidal tendency using quantitative EEG measurements. There is limited preliminary work focusing on EEG performance and coherence. Most of these studies were performed in adults. No previous studies have examined EEG coherence in adolescents with suicidal ideation and behavior.

Methods:Thirty adolescents, aged 13 to 18 years, admitted to a psychiatric inpatient unit with suicidal ideation and behavior (as assessed by the Columbia-Suicide Severity Rating Scale (C-SSRS)) and thirty without previous psychiatric diagnoses were recruited. All participants underwent diagnostic tests and resting EEG recordings. Three patients discontinued the study before completing the EEG recordings. The group of hospitalized patients was further divided into 2 subgroups according to the C-SSRS score, those with suicidal ideation (n=9) or suicidal behaviors (n=18). ANCOVA models were used to test whether intrahemispheric coherence differed between age and sex controlled groups. Bonferroni correction was used for post hoc comparisons.

Results:Patients with suicidal behavior (SB) had greater delta (p = 0.024), alpha (p = 0.024) and beta (p = 0.006) coherence in the right PFC (Fp2-F4) compared to patients with suicidal ideation (SI ). The SB group also had greater delta power (p = 0.027) over the left parieto-occipital cortex (P7-01) compared with the SI group. In the right temporoparietal (T8-P8) and centroparietal (C4-P4) cortex, the SB group showed lower theta (p = 0.036), alpha (p = 0.045) coherence compared to healthy controls. Depression severity (assessed using the Revised Depression Rating Scale for Children) did not differ between the SB and SI groups only (p > 0.05).

Conclusions:SB patients showed greater intrahemispheric coherence within the right prefrontal cortex for higher and lower frequencies, except theta coherence, but decreased coherence in temporoparietal centroparietal cortex. These results may indicate an altered default mode network and inhibitory mechanisms in patients with recent suicidal behavior compared to those with suicidal ideation. Given the lack of research in this area, more research is needed to replicate the results in larger samples.

Key words:EEG, adolescent, suicide, suicidal behavior, suicidal thoughts

Disclosures: Neuronetics, Magventure: other financial or material support (author), Engrail Therapeutics, Sunovion, Myriad Neuroscience, Procter and Gamble Company: advisory board (authority)

Michael McCarthy, Connor McCabe, Alejandro Meruelo*

University of California, San Diego, San Diego, California, USA

Background:Chronotype features a tendency to be morning or evening (eg larks vs. night owls). Association studies increasingly support the relevance of chronotype to the development of depression, diabetes, alcohol use disorders, cannabis use disorders, and obesity. Chronotype is regulated by development and shows the greatest changes in adolescence, precisely at the time when many psychiatric disorders are identified for the first time and important changes in brain myelination occur. However, much less has been investigated and studied whether chronotype or eveningness play a role in the development of some of these disorders.

Several studies have examined the relationship between trauma and chronotype and have found an association between childhood trauma and preference for an evening chronotype, suggesting mediation by emotional dysregulation. However, the relationship between stressful life events and chronotype has not been studied as thoroughly.

Some genome-wide studies have linked the chronotype more prominently to the anterior cingulate as a potential neuroanatomical phenotype that may be related to either chronotype or vesperticity. Greater anterior cingulate activation was observed during suppression of negative emotion versus maintenance of negative emotion. To function properly, the brain requires myelin, an electrically insulating structure that surrounds axonal fibers. Based on fractional anisotropy imaging, poor sleep quality or short sleep duration have been shown to be associated with lower myelin content in human neocortex. Intracortical myelin in the anterior orbitofrontal cortex mediates the association between sleep deprivation and negative emotionality, which may mechanically explain how sleep deprivation affects affective behavior. Diffusion tensor imaging, such as B. Fractional anisotropy, is sensitive to the degree of myelination of anatomical structures such as the anterior cingulate.

Methods:The Adolescent Brain Cognitive Development (ABCD) study provides a large sample of approximately 11,000 high-risk adolescents followed over a 10-year period with data from chronotyping, neuroimaging, and stressful life events. This study traces biological and behavioral development from adolescence to early adulthood. We used a mediation model to examine the relationship between chronotype, anterior cingulate fractional anisotropy, and stressful life events using the Munich Chronotype Questionnaire (MCTQ) and Life Event Scale. In our final comprehensive model, we included race, gender, and socioeconomic status as covariates to control for. All analyzes were performed in R using Lavaan.

Results:We found that cross-sectional data suggest a possible relationship between chronotype and anterior cingulate myelination mediated by stressful life events. Less myelination of the anterior cingulate was associated with more uniformity.

Conclusions:Our work provides new insight into the interrelationship between chronotype, myelination, and stressful life events in the ABCD study. Understanding the role of myelination in stress in people predisposed to nighttime mood swings is helpful, as it may improve our understanding of the biological mechanisms that contribute to stress and may lead to better prevention and treatment efforts, increasing interventions such as lifestyle and exposure. the light at night. day are used.

Key words:Chronotype, myelination, youth, ABCD, stress

To disclose:Nothing to disclose.

Amanda Lyall*, Shreyas Fadnavis, Suheyla Cetin-Karayumak, Fan Zhang, Ofer Pasternak, Lauren J. O'Donnell, Yogesh Rathi

Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, EUA. UU.

Background:Adolescence is a critical period of life between late childhood and adulthood, characterized as the second largest and fastest period of development after childhood. As a result, adolescence has been recognized as a critical period of heightened vulnerability, where exposure to environmental and social stressors can have long-term functional and structural effects beyond the effects of puberty hormones or other life events.

Food insecurity is a growing public health problem in the United States and around the world. Food insecurity is defined as the lack of means to obtain reliable access to an adequate amount of food needed for a healthy diet. In the United States, approximately 14.8% of households are food insecure and approximately 7% of those with low or very low food insecurity are children (6.1 million children). While food insecurity is not necessarily synonymous with extreme states of hunger, starvation or malnutrition, it can result in limited or unequal access to healthy food and nutrients. Past reports show that while very young children are often protected from the effects of food insecurity, teenagers are often at greater risk. This lack of access to adequate dietary resources and nutrients can be detrimental during this critical period of brain development, particularly for the white matter of the brain, which actively matures during adolescence.

White matter is made up of a lipid-rich substance called myelin that wraps around neuronal axons to provide insulation and increase the speed at which electrical impulses travel down the axon. The formation and maintenance of myelin are controlled by oligodendrocytes, which demand a series of resources such as iron, fatty acids and several vitamins, such as vitamin D and vitamin K, whose concentration depends mainly on food intake. As a result, the developing white matter may be particularly vulnerable to the potential underresource created by inconsistent or limited access to nutritious food that occurs in nutritionally insecure families. However, to date, no neuroimaging studies have been performed to investigate whether food insecurity influences or influences white matter development in children and adolescents.

In this study, we will use existing data from the Adolescent Brain and Cognitive Development (ABCD) study to assess the extent to which food insecurity may affect overall white matter health in children and adolescents aged 9 to 15 years. More importantly, given the complex interplay between food insecurity and other factors known to affect brain development (e.g., the link between food insecurity and changes in white matter health, independent of the effects of other environmental, financial, or social stressors) .

Methods:Of the 11,877 individuals included in the initial ABCD sample, 954 parents (8%) reported having had a food insecurity event in the past 12 months. We will apply propensity score matching using K nearest neighbors to construct comparable groups of food insecure (FI) children/adolescents that are matched in terms of age, gender, race, ethnicity, IQ and, where possible, years of education from parents/or socioeconomic level, to children/adolescents without food insecurity (without FI).

For image data from individuals included in our identified groups, we will use diffusion magnetic resonance image data, which has already been preprocessed and harmonized across all 21 imaging sites, as part of an ongoing effort funded by the NIMH and led by Dr. Rathi. A two-tensor total brain tractography was performed and quality checked. An unsupervised fiber cluster atlas (white matter analysis) was applied and will be used to extract the mean fractional anisotropy (FA) of the whole brain for each participant in this sample.

Results:Statistical analyzes of this study are currently in progress. We will train a machine learning model to determine whether the corresponding FI cohort has differences in mean whole-brain AF from the non-FI cohort. To understand the covariance structure of the variables used to train the model, we use an interpretability approach that allows for mediation analysis and classification of variables based on learned weights. This will allow us to understand the relative importance of food insecurity for white matter health in children/adolescents, independent of the impact of other confounders such as B. Socioeconomic status.

Conclusions:To the best of our knowledge, this will be the first study to determine whether there is an association between food insecurity and white matter microstructure in children and adolescents. This study will serve as a first step in advancing our understanding of the role that access to healthy, nutritious food can play in brain development.

Key words:White matter development, ABCD, food insecurity

To disclose:Nothing to disclose.

Joseph Aloi, Kathleen Crum, John Nurnberger, Leslie Hulvershorn*

Indiana University School of Medicine, Indianapolis, Indiana, USA

Background:Risky decision-making is associated with the development of substance use behaviors during adolescence. Although previous work has examined risky decision-making in adolescents at high familial risk of developing substance use disorders (SUDs), little research has controlled for the presence of comorbid externalizing disorders (EDs), another risk factor for SUDs. Furthermore, few studies have examined the role of parental impulsivity in offspring neurobiology related to risk decisions. The aim of this study was to fill these gaps in the literature by (i) examining differences in neural function during risk decision making in children with externalizing disorders with and without a family history of SUD; and (ii) examine the relationship between parental impulsivity and children's neural function during risky decision-making. Based on previous work on decision-making and the neurobiology of children at risk for DUB, we hypothesize that children with a comorbid family history of DUB and ED may be more responsive to negative outcomes of risky decisions in the anterior insular cortex (aIC) , rostral, show the anterior cingulate cortex (ACC) and lateral orbitofrontal cortex (OFC) compared to psychiatric controls and healthy controls and that these differences would be related to parental impulsivity.

Methods:One hundred twenty-five children (28 healthy controls, 47 psychiatric controls (PC) with ED without a family history of SUD, and 50 high-risk (HR) children with comorbid ED with a family history of SUD) participated in the Analog Balloon Risk Task (BART) during a functional magnetic resonance imaging. Parental and child impulsivity was measured using the UPPS-P Impulsive Behavior Scale. AIC, rostral ACC, and lateral OFC were defined as regions of structural interest (ROI) using Freesurfer plots from the Desikan-Killiany atlas. A 3 (Group: HC, PC, HR)-times-2 (Laterality: Left, Right)-times-3 (Region: lOFC, rACC, aIC)-times-2 (BART Choice: Inflate, Gain) ANCOVA repeated measures was performed using BOLD response data modulated by the probability of a balloon bursting from these regions of interest. The covariate of interest in this ANCOVA was parental impulsivity; this analysis was also repeated, including childhood impulsivity as a covariate of no interest.

Results:We found that subjects in the psychiatric control group showed greater arousal, as the likelihood of popping the balloon was increased when making decisions, compared to healthy controls and high-risk groups in the rostral ACC and lateral OFC. We also found a positive association between increased parental arousal and impulsivity in these regions. However, within the rostral ACC, this relationship was moderated by group, such that there was a positive relationship between parental arousal and impulsivity in the HC group, but an inverse relationship in the HR group. These relationships remained significant when controlling for childhood impulsivity.

Conclusions:These results suggest that there are significant differences in the neurobiology underlying risk decision-making in people with eating disorders with and without a family history of SUT. These data also indicate that the association between parental impulsivity and rostral ACC activity during risk decision making may be a marker of future DUB risk. We propose that the development of biomarkers for DUB risk (based on these findings) will provide more information to determine DUB risk levels in different populations. However, further work is needed on the role of how altered rostral ACC and lateral OFC activity may pose a risk to SUD and the longitudinal follow-up of high-risk specimens.

Key words:Comorbidity dependence, alcohol consumption and drug dependence, impulsivity

To disclose:Nothing to disclose.

Layla Banihashemi*, Vanessa Schmithorst, Michele Bertocci, Alyssa Samolyk, Joao P. Lima Santos, Amelia Versace, Megan Taylor, Gabrielle English, Jessie B. Northrup, Vincent K. Lee, Richelle Stiffler, Haris Aslam, Ashok Panigrahy, Alison Hipwell, maria phillips

University of Pittsburgh, Pittsburgh, Pennsylvania, USA

Background:Low positive emotionality (PE) scores and high negative emotionality (NE) scores in childhood indicate a risk for later emotional and behavioral problems. Elucidating the neural basis of these childhood temperament traits may identify objective biomarkers of risk that reflect underlying pathophysiologic processes. Our aim was to determine how functional interactions between large-scale neural networks that support emotion regulation affect microstructural, emotional, and behavioral white matter relationships in 3-month-old infants. We hypothesize that microstructural-emotional-behavioral relationships are differentially mediated or repressed by underlying resting-state functional connectivity, particularly between the Central Executive Network (CEN) and Default Mode Network (DMN) structures.

Methods:This sample included caregiver-infant dyads [52 infants (42% female, mean age at examination = 15.10 weeks) and their primary caregiver (98% biological mother)], with assessments of infant neuroimaging and infant emotional behavior at 3 months old. The infant's white matter and functional connectivity were assessed by resting diffusion-weighted imaging/tractography and magnetic resonance imaging (MRI) during natural sleep without sedation. The Infant Behavior Questionnaire-R provided measures of infant PE and EN. After significant relationships between white matter and emotional behavior, multimodal analyzes were performed using whole brain mediation in the form of voxels.

Results:The results showed that a larger cingulate tract volume was significantly associated with lower PE in childhood (ß = -0.263, p = 0.031); however, this negative relationship abolished (ie, reduced) a pattern of lower functional connectivity between the CEN and DMN structures. A larger volume of the uncinate fasciculus was significantly associated with a smaller EN in childhood (ß = -0.296, p = 0.022); However, functional connectivity between the inferior orbitofrontal cortex (OFC) and amygdala (supports emotion regulation) suppressed this negative relationship, whereas increased OFC-CEN functional connectivity (supports executive control over emotions) mediated (i.e. , facilitated) this relationship.

Conclusions:Functional interactions between neural networks have a major impact on microstructural, emotional, and behavioral white matter relationships in infancy. These relationships may elucidate the neural mechanisms that contribute to later emotional and behavioral problems in childhood.

Key words:Infant brain, infant emotionality, multimodal neuroimaging, diffusion-weighted imaging, resting-state functional connectivity

To disclose:Nothing to disclose.

Rebecca Brady*, Cynthia Rogers, Trinidi Prochaska, Tara Smyser, Barbara Warner, Deanna Barch, Joan Luby, Christopher Smyser

Washington University School of Medicine, St. Louis, Missouri, USA

Background:Growing up in a crime-ridden area has been linked to sleep disturbances, mental health issues and altered brain function. Our previous study found that prenatal exposure to neighborhood crime was associated with reduced frontolimbic connectivity in the newborn brain, mediated in part by maternal psychosocial stress (Brady et al. 2022). It is not known whether antenatal delinquency and subsequent brain changes in newborns lead to behavioral changes in childhood or later. It is plausible that prenatal delinquency is related to later behavior, as studies in early childhood and adolescence show an association between living in a high-crime area and mental health problems. We hypothesize that prenatal exposure to crime is associated with worse socio-emotional outcomes mediated by both maternal psychosocial stress and neonatal frontolimbic connectivity.

Methods:The study used a longitudinal cohort of 399 women recruited during pregnancy as part of the eLABE study at the University of Washington. Prenatal addresses were collected for each mother and coded by census block group. Crime data for each block group was obtained from Applied Geographic Solution's CrimeRisk database. Violent crimes (eg, murder, rape, aggravated assault, robbery) and property crimes (eg, burglary, larceny, vehicle theft, arson) were examined. In the neonatal period (mean postmenstrual age at examination = 41 weeks), 319 unsedated infants (male sex = 55%, mean gestational age = 38 weeks) underwent fMRI sequence in resting state (TR = 800 ms, TE ) = 37 ms, voxel size = 2.0 × 2.0 × 2.0 mm3, MB = 8) on a Prisma 3T scanner and had at least 10 minutes of high quality quiescent state data after pre- and post- processing, including strict motion correction. At one year of age, mothers of 293 infants completed the Infant and Toddler Socio-Emotional Assessment (ITSEA), which includes information on four domains of behavior: externalizing, internalizing, dysregulation, and competence. Pearson correlations were used to examine the relationship between group crime in block areas and ITSEA t scores. Linear models examined the relationship between significant frontolimbic connections in Brady et al. 2022 (ie, thalamic default mode network (DMN), thalamic anterior frontoparietal network (aFPN), amygdala hippocampus, and amygdala DMN), and relevant t ITSEA scores controlled for gestational age at birth and examination. Results were corrected for multiple comparisons using an FDR procedure. Structural equation models (SEM) were constructed to test whether maternal psychosocial stress and neonatal neuroimaging mediated the relationship between prenatal crime and ITSEA t-scores. To assess the specificity of exposure to crime compared to other forms of adversity, a composite measure of deprivation experienced during pregnancy (income needs, area deprivation rate, education, insurance status, and healthy eating index) was included.

Results:The results of this study showed that prenatal exposure to high levels of violent crime in the neighborhood was associated with higher T-scores for externalizing (q<0.001), internalizing (q=0.03) and dysregulation (q<0.001) . , but not competently, is related to t-scores (q = 0.31) at age 1 year. Living in an area with a high rate of property crime during pregnancy was also associated with higher t scores for externalizing (q = 0.001) and dysregulation (q < 0.001), but not for internalizing (q = 0.06) or competition (q = 0.81). All of these relationships remained significant after disadvantage was added to the models, with the exception of the relationship between violent crime and internalized symptoms. Frontolimbic connections in the newborn brain, particularly thalamic DMN (q = 0.05; q = 0.005), thalamic aFPN (q = 0.03; q = 0.004) and amygdala DMN (q = 0.02; q = 0.005), associated with externalization of T-scores and dysregulation T-scores, respectively. Connectivity between the amygdala and hippocampus was not associated with externalization or dysregulation of T-scores. In SEM models that predict externalizing symptoms of violent crime, the direct relationship with violent crime remains significant, but mediation does not. In SEM models that predict dysregulation symptoms, the indirect pathway through maternal psychosocial stress and thalamic aFPN mediated the relationship between adversity and dysregulation symptoms. Furthermore, there were direct relationships between thalamic DMN and amygdala DMN and dysregulation scores. For property crimes, SEM models showed that direct relationships with crime and deprivation independently predicted symptoms of externalization and dysregulation.

Conclusions:These results provide evidence that exposure to a high-crime environment in utero is associated with worse socio-emotional processing in the domains of externalization and dysregulation at one year of age. Crime appears to be the most important predictor of externalizing symptoms, while frontolimbic connectivity appears to be the most important predictor of dysregulation symptoms. A limitation of this analysis is that it does not consider defaults in the first year, but this is a planned future direction of the study. However, current findings suggest that exposure to crime and the neonatal brain in utero may affect socio-emotional functioning. Given the impact of prenatal crime, this study reinforces the need to reduce neighborhood crime rates and promote the development of frontolimbic connectivity.

Key words:Pregnancy, neighborhood crime, functional magnetic resonance imaging (fMRI), stress and adversity, child behavior

To disclose:Nothing to disclose.

Hellen Weinschutz Mendes, Uma Neelakantan, Yunqing Liu, Sarah Fitzpatrick, Tianying Chen, Weimiao Wu, April Pruitt, David Jin, Kristen Enriquez, Cheryl Lacadie, Ningshan Li, Dejian Zhao, Marina Carlson, Sundas Ijaz, Catalina Sakai, Christina Szi, Brendan Rooney, Marcus Ghosh, Ijeoma Nawabudike, Jeffrey Eilbott, Brent Vander Wyk, Jason Rihel, Xenophon Papademetris, Zuoheng Wang, Ellen Hoffman*

Yale University, New Haven, Connecticut, USA. UU.

Background:Complete studies of exome sequencing in autism spectrum disorders (ASD) have led to the identification of a growing list of high-confidence risk genes (hcASD). These genes converge on biologically relevant mechanisms, including fetal milieu glutamatergic projection neurons, chromatin modification and synaptic function, and provide new insights into the underlying biology of ASD. At the same time, understanding how loss of hcASD gene function affects specific cell types and the establishment of neural circuits in the developing vertebrate brain remains a fundamental challenge.

Methods:Here, we explore the unique advantages of zebrafish as a high-throughput in vivo system to analyze the function of 10 hcASD genes in parallel at the behavioral, structural, and circuitry levels. First, we mutated the zebrafish orthologs of 10 hcASD genes using CRISPR/Cas9. These genes span a variety of biological functions, including regulation of gene expression (CHD8, CUL3, KDM5B, POGZ, TBR1), neuronal communication (CNTNAP2, SCN1A/SCN2A, GRIN2B), and the cytoskeleton (DYRK1A, KATNAL2). Second, we performed high-throughput automated assays of visual startle and sleep-wake behavior to determine how loss of gene function affects key behaviors. Third, we developed a new computational pipeline to analyze all brain structure and activity across all mutant strains in parallel. Fourth, to identify overlapping molecular signaling pathways, we performed whole-brain RNA sequencing on three mutants with the most robust behavioral and brain activity phenotypes.

Results:We established a new high-throughput pipeline for parallel functional analysis of 10 hcASD genes in zebrafish and identified several points of convergence and divergence between risk genes at behavioral, structural, circuitry and molecular levels. First, we identified unique behavioral fingerprints that affect arousal and sensory responsiveness in hcASD gene mutants. Second, we identified the forebrain as a significant contributor to differences in brain size among mutants. Third, by mapping total brain activity, we found that regions involved in sensorimotor control exhibit altered basal brain activity and identified 22 of 149 regions in the zebrafish brain with significant differences in basal brain activity in more than half of the brains. mutants. Fourth, the RNA-seq reveals conservation of signaling pathways associated with the ASD gene, including neurogenesis and FMRP targets, and implicates novel cellular mechanisms in a subset of mutants.

Conclusions:High-throughput parallel in vivo analysis of 10 ASD risk genes in zebrafish identifies converging phenotypes that affect brain structure and basal activity and reveals common molecular and cellular signaling pathways in a subset of mutants.

Key words:Autistic Spectrum Disorder Genetics Zebrafish Neurodevelopment

To disclose:Nothing to disclose.

Jennifer Bruno, Paige Naylor, Tamar Green*

Stanford University, Stanford, California, USA

Background:The Ras mitogen-activated protein kinase (Ras-MAPK) pathway is critical for neurodevelopment. Noonan syndrome (SN), the most common disorder associated with pathogenic variants of Ras MAPK, is associated with highly variable neuropsychiatric outcomes. We address the limitations of previous research, focusing on prepubertal children, comparison with typically developing children (TD), comprehensive neuropsychiatric assessment, and monitoring of general cognitive abilities.

Methods:Forty-five NS children (8.48+/-2.13 years; 29 girls) and 40 TD children (8.75+/-1.96 years; 22 girls) were assessed using objective parent reports and measures of interview.

Results:Children with NS exhibited higher levels of Attention Deficit Hyperactivity Disorder (ADHD) (attention, hyperactivity and inhibition), Autism Spectrum Disorder (ASD) (maintenance of social relationships, behavioral rigidity and sensory sensitivity) compared to children with NS with TD compared with TD children, all effect sizes p<0.05 and η2 were in the broad range (>0.14). NS children also showed higher levels of oppositional defiant disorder (ODD) symptoms (aggressiveness) compared to TD children (all p-values ​​< 0.05, η2 effect sizes were in the middle range). Forty-eight percent of children with NS met criteria for ADHD, 19% for ODD, and 25% had clinically significant symptoms seen in children with ASD.

Conclusions:Children with NS are at increased risk for a spectrum of symptoms related to ADHD, ASD and ODD. More than 50% of children met criteria for at least one of the evaluated clinical diagnoses. In contrast to the currently accepted categorical diagnostic approach, a dimensional approach reveals significant ASD symptoms in NS.

Key words:ADHD, Neurodevelopment, Noonan Syndrome, ASD

To disclose:Nothing to disclose.

Lauren Schmitt*, Christina Gross, Kelli Dominick, Ernest Pedapati, Craig Erickson

Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, EUA.

Background:The specific fragile protein product of the X-messenger ribonucleoprotein 1 (FMR1) gene, FMRP, is essential for brain development. In fragile X syndrome (FXS), FMRP levels are markedly reduced, if not absent. Previous studies have shown the relationship between FMRP levels and overall cognitive function; However, due to limitations of available assays, FMRP could not be reliably and reproducibly detected at extremely low levels, which has prevented investigation of clinical associations across the spectrum of people with FXS. Identifying these relationships can be critical to planning clinical care and understanding how it evolves over time.

Methods:A sample of 65 subjects with FXS ( >200 CGG repeats; 67% male) aged between 8 and 45 years underwent a series of psychosocial, neurocognitive, and electrophysiological measurements. Whole blood samples from participants were collected by venipuncture and tested using our validated Luminex-based immunoassay for FMRP levels. Pearson correlations were performed to examine the relationship between FMRP levels and clinical phenotypes.

Results:In men and women with FXS, higher levels of FMRP were associated with higher IQ scores (m: r2 = 0.20, p-0.01; f: r2 = 0.24, p = 0.02), in line with previous results. In particular, fully methylated and fully mutant males producing little or no FMRP have a left skew (mean = 25, standard deviation = 15), but otherwise a normal distribution of IQ scores (skew = 0.15, kurtosis = 0.82). In men only, higher FMRP levels were associated with less severe stereotyped behavior (r2 = 0.12, p = 04) and irritability (r2 = 0.10, p = 07). Only in females were FMRP levels unexpectedly higher associated with greater social avoidance (r2 = 0.40, p = 0.04) and depressive symptoms (r2 = 0.58, p = 0.01). FMRP levels were not significant with respect to executive function variables in men or women with FXS. However, lower levels of FMRP were associated with increased relative gamma potency, a neurophysiological biomarker of neural hyperexcitability, in patients with FXS (r2 = 0.14, p = 0.04).

Conclusions:Together, our optimized FMRP assay provides new evidence for the link between FMRP expression and neurophysiological and clinical phenotypes in FXS, and more importantly, these relationships may differ based on biological sex. Furthermore, our results also provide a paradigm-shifting role for FMRP on cognitive function in fully mutant males: FMRP drives leftward shift in IQ but does not account for residual variation in cognition in fully mutant males. complete with FXS. This is in contrast to our findings and others that suggest that FMRP has a dose-dependent effect on IQ in mosaic males and full-mutation females, which express higher levels of the protein. There is much future work to better understand the mechanism by which deficient or absent FMRP results in a clinical phenotype. However, our new work is a crucial step towards establishing molecular markers for disease severity in FXS. Ultimately, this seminal work paves the way for the development of individualized "precision medicine".

Key words:Fragile X syndrome, FMRP, biomarker

To disclose:Nothing to disclose.

Nativity Avila*, GALA Consortium, Joseph Buxbaum

Icahn School of Medicine at Mount Sinai, New York, New York, United States of America

Background:Autistic Spectrum Disorder (ASD) is characterized by deficits in social communication and the presence of restricted interests and/or repetitive behaviors. ASD risk is complex but largely genetic, with both common and rare genetic variations contributing to the risk. While the more common variation explains genetic responsibility for ASDs, the rare variation, often de novo, explains significant individual responsibility.

Anticipating the tremendous impact and resulting challenges that high-throughput sequencing would have on ASD genomics, the Autism Sequencing Consortium (ASC) was formed in 2010 and has recently completed an analysis of 65,000 exomes (Fu et al. 2022, in press). , which included samples from ASC sites as well as SPARK data (SPARK Consortium 2018). In Fu et al. the ASC reported 71 genes associated with ASD with a false detection rate (FDR) ≤ ≤ 0.001; a threshold approaching exome-wide significance (p < 2.5e-6) and 185 genes at FDR ≤ 0.05. Analysis of the SPARK dataset identified 60 largely overlapping genes of full exome importance (Zhou et al. 2022, in press).

Despite the success of these large-scale genetic analyses, the question remains whether the genetic architecture of ASD differs between ancestral populations. In particular, no systematic effort has been made to study the genetic architecture of ASDs in Latino/Latino (hereafter Latinx) populations, the largest minority in the United States.

We established the Genomics of Autism in Latinx Ancestrys (GALA) consortium to build a large prospective cohort to study the role of genetic and environmental factors in ASDs through ancestral histories and collect genetic material for large-scale analysis. Our first goal was to investigate whether the rare signal of harmful stress is similar across all ancestors. In parallel, we are testing new and existing GALA samples and other Latinx samples for ASD gene discovery.

Methods:The GALA consortium has approximately 1,000 ASD Latinx participants, mostly trios from South and Central America and/or the United States. The collection of another 1,600 Latinx ASD trios is in progress. All sites use a similar strategy to test and rate individuals. All samples undergo genotyping and complete exome sequencing (WES). Single nucleotide polymorphism (SNP) data are used to estimate SNP-based heritability at different pedigree levels. Rare de novo and inherited single nucleotide variations (SNVs) and insertion-deletion (indel) variations are identified by WES. Chromosomal microarrays and WES data will identify potentially harmful copy number variations (CNVs). Using these data, we will first test whether the genomic architecture of ASD, as reflected by (a) de novo exonic rate, (b) mutational load in highly conserved genes (pLI ≥ 0.995), and (c) polygenic risk, reflecting differences between populations latinas and non-latinas. With ancestry in mind, we will use the TADA (Transmitted and De Novo Association) framework to identify Latinx ASD genes affected by rare variations and integrate de novo and inherited variations from triads and case control data, including SNV, indel, and CNV. 🇧🇷 GALA SNP data will be contributed to PGC-ASD analyzes to allow higher yield for cross-line GWAS.

Results:We first determined whether genomic architecture and ASD genes affected by rare deleterious variations differed between ancestors. We assume this will not be the case. To investigate this, we removed all de novo mutations in Fu et al. and studied rates based on ancestry. We looked at highly conserved genes and all the remaining genes. We observed that the signal is predominantly found in the most conserved genes of all ancestors. Therefore, when the samples were separated by genetically defined ancestry, the results were similar in all groups. We are now analyzing WES data from existing and emerging GALA samples, along with SPARK's Latinx samples. Gene discovery power can be estimated based on these results, and it is reasonable to estimate at least 25 ASD genes in the full GALA Latinx samples at a strict FDR < 0.05 and more at softer bounds. The genetic findings will be compared with those from the European samples and, if the genes overlap as we predicted, we will do a pooled analysis of multiple ancestors. GALA's initial results implicate already known ASD genes that are consistent with a common molecular risk architecture. Analyzes are in progress and the results of all analyzes are displayed.

Conclusions:Genetic variations with a strong impact on neurodevelopment are predominantly found in highly conserved genes; those that suffer deleterious fluctuations in very large and heterogeneous databases. Therefore, we hypothesize that the rare mutational load in conserved genes will not differ between ancestors and that there will be a large overlap between identified ASD genes. Our analyzes are consistent with this hypothesis and support the continued discovery of ASD genes in Latinx and other populations. The biology reflected here in genes that do not tolerate detrimental variation due to critical function and dose sensitivity is universal and unaffected by "local" genetic processes.

In the future, we will be able to perform genotype-phenotype correlations in Latinx samples and investigate the role of access to care on phenotype and genomic architecture. As we move from studying rare harmful variants to existing inherited variations, improved methods are needed to integrate data across populations.

Key words:ASD, rare genetic variation, multiple ancestry, copy number variation, gene discovery

To disclose:Nothing to disclose.

Kelli Dominick*, Elizabeth Smith, Lauren Schmitt, Craig Erickson

Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, EUA.

Background:Fragile X syndrome (FXS) is the most common inherited cause of intellectual disability (ID) resulting from silencing and inactivation of the FMR1 gene with consequent loss of fragile X messenger ribonucleoprotein (FMRP) expression, resulting in widespread changes in brain structure and function. Although language delays are nearly universal in people with FXS, there is limited research examining auditory and language processing, particularly in early life and in men. And few have studied the relationship between FMRP and the brain's functional response to language in FXS. Here, we examine the relationship between FMRP levels and neural activation of speech and non-speech sounds using fNIRS.

Methods:Participant. The current sample includes 38 full mutation FXS (diagnosis determined by genetic testing) and 15 normally developing controls. Eighteen of the 38 FXS participants also had blood drawn to measure FMRP levels.

fNIRS. All fNIRS data was collected using a custom NIRx NIRScout device (NIRx Medical Technologies, Brooklyn, NY) with lasers at wavelengths of 685 and 830 nm and a sampling rate of 7.8125 Hz with a 2x2x4 ear pad designed to do so, it covers areas of the temporal lobe bilaterally, including the primary auditory cortex. Data were collected using the NIRStar acquisition software, with auditory stimuli programmed and presented using the NIRStim software.

listening task. The experimental design was a passive listening task lasting approximately 20 minutes (variable due to jitter, actual time was 1208 seconds plus or minus up to 68 seconds of jitter). The listening task consisted of a modified version of the Stories paradigm created by Cincinnati MR Imaging of Neurodevelopment (C-MIND) (Schmithorst, Holland and Plante, 2006; Sroka et al., 2015). Clips of 5 narrative stories for young children read by a female voice interspersed with uncontrolled speech tones tuned to human speech (center frequencies 200-4000 Hz, wideband sweep 0.5-2.0 Hz duration).

FMRP. FMRP was measured using an optimized Luminex-based assay (Boggs et al. 2022) capable of detecting a wide range of FMRP levels, including very low protein levels. Blood processing has been completed on 11 of the 18 FXS subjects to date, with more subjects to be added for final analysis.

data analysis. The fNIRS data was then processed using Homer3's Toolbox (https://github.com/BUNPC/Homer3🇧🇷 Arousal patterns to verbal and non-verbal stimuli were examined in relation to FMRP levels in FXS participants.

Results:Children with FXS showed activation for speech and non-speech sounds in the speech regions. Controls showed activation for speech and neural differentiation between speech and non-speech stimuli. FMRP showed a negligible relationship with neuronal firing patterns in early analyses. Additional analyzes will be performed on the entire cohort, including examining the relationship between FMRP and language lateralization. Descriptive statistics are used to characterize men versus women with FXS, however, a small sample size will limit further subgroup analyses.

Conclusions:Effective biomarkers of language and developmental impairment in FXS require an understanding of the mechanisms that lead to impairment, which in turn requires functional neuroimaging methods such as fNIRS. Ideally, it involves linking neural changes to both phenotypic presentation and molecular etiology. This work provides initial investigation into the relationship between peripheral FMRP and neural firing patterns in FXS.

Key words:Speech delay, fragile X syndrome, fNIRS

To disclose:Nothing to disclose.

Sunday Francis*, Lindsay Oberman, Megan Hynd, Lysianne Beynel, Zeynab Rezaee, Paul Rohde, Jeff Stout, Joelle Sarlls, Jan Willem van der Veen, Audrey Thurm, Sarah Lisanby

National Institute of Mental Health, Bethesda, Maryland, USA.

Background:Language processing challenges are a central feature of autism spectrum disorder (ASD), a complex and heterogeneous neurodevelopmental disorder that also includes repetitive and impaired behaviors and deficits in social interaction. Previous literature suggests that dysfunctional transmission of γ-aminobutyric acid (GABA) may be behind auditory processing and speech deficits in people with ASD. With recent advances in neuroimaging and neurophysiology technologies, researchers may be challenged with clinical investigations that examine GABAergic and other neurochemical transmissions, as well as structural and functional connectivity, in the context of the pathophysiology of brain deficits. auditory and speech processing.

The pilot phase of this study presented here has several purposes: (1) confirm the feasibility and tolerability of the study procedures, (2) develop and test the performance of new processing and analysis channels, (3) establish the relationship between local neurochemical concentrations in Wernicke's area, structural and functional network connectivity, and magnetoencephalographic (MEG) indices of auditory and verbal processing, and (4) examine the effect of a single session, individually directed, continuous theta burst stimulation (cTBS) on the above results in 20 non-clinical adult volunteers. Individualized stimulation targets are determined by maximal task-related activation within the left posterior superior temporal cortex (pSTC) during the Auditory Description Decision Task (ADDT). We used magnetic resonance spectroscopy (MRS) to quantify neurochemical concentrations (including GABA, glutamate, glutamine, N-acetylaspartate (NAA) and creatine) in the target region. Diffusion Weighted Images (DWI) are collected to examine structural connectivity. Functional magnetic resonance imaging (fMRI) is acquired to assess activation and functional connectivity at rest and during the language task, and MEG is performed to understand temporal aspects of auditory processing. Together, these measurements provide a comprehensive and general picture of the brain mechanisms underlying speech and auditory processing.

Methods:Twenty nonclinical participants (5 men, 23.15 ± 0.97 years) underwent MEG, MRI, and MRS at baseline, after which two cTBS visits were performed at least one week apart. During cTBS visits, pre- and post-stimulation MEG (MEG visit + TMS), MRI and MRS (MRI visit + MRS + TMS) visits were collected.

MEG data were collected using a CTF 275 full-head MEG (sampling rate 1200 Hz) while participants listened to validated auditory stimuli designed to assess evoked power and coherence between trials in the gamma frequency band as well as in the network. local and long range. function (measured by phase amplitude coupling between the alpha and gamma frequency bands and the latency of evoked fields such as M100 and MMF). All MRI and MRI scans were acquired with a General Electric (GE) 3T MRI scanner. A 15.6 cm3 voxel centered around the individually defined target was used for spectroscopy. A single cTBS session consisted of 200 bursts of 3 pulses at 50 Hz with an interval between bursts of 200 ms for a total of 40 s. Stimulation was applied at 80% of the active motor threshold.

Results:At the time of the presentation, all 20 participants were registered. There were no serious events reported; In fact, all volunteers tolerated all procedures. The first objective of confirming the feasibility and tolerability of the study procedures was achieved. Second, processing and analysis pipelines are developed and tested. The language processing task used to target TMS reliably (p ≤ 0.05) activated a defined region within the pSTC for each participant. An acute effect of cTBS on MEG measurements was also observed. Data analysis is in progress. Inferential statistics results will be presented at the annual conference.

Conclusions:We present baseline and pre-post cTBS Phase I data examining the relationship between local neurochemical transmission, structural and functional network connectivity, and MEG indices associated with auditory and language processing networks in 20 non-adult adult volunteers. In addition to observing the effects of cTBS on auditory and speech processing, this phase serves to demonstrate the feasibility and tolerability of the study procedures and allows the development of lines of multimodal image analysis for the main phase of the study, which will include 86 adolescents ( 14 to 17 years old) with ASD.

Key words:Human neuroimaging, multimodal neuroimaging, repetitive transcranial magnetic stimulation (rTMS), autism spectrum disorder, auditory processing

To disclose:Nothing to disclose.

Molly McVoy*, Deniz Doruk Camsari, Farren Briggs, Farhad Kaffashi, Kenneth Loparo, Paul Croarkin

Case Western Reserve University, Cleveland, Ohio, USA. UU.

Background:Early detection, accurate diagnosis, and determination of prognosis in adolescents with major depressive disorder (MDD) are challenging. Imprecise nosology and overlapping presentations are especially difficult in childhood (Mendelson & Tandon, 2016). As a result, there is an unmet need for evidence-based biomarkers in the psychiatric diagnosis of children.

We previously reported in a biomarker pilot study that quantitative electroencephalogram (qEEG) showed a difference in coherence (a measure of resting state connectivity) between an outpatient sample of adolescents with major depressive disorder (MDD) and healthy controls (HC ). Adolescents with MDD showed a pattern of decreased coherence compared to HC. We developed a predictive model or diagnostic classifier in a pilot sample of adolescents with MDD using EEG measures of coherence, strength, and cross-correlation.

We present a new sample of patients admitted with MDD and measures of connectivity and suicidality measured by qEEG versus HC. In addition, we report new findings on the application of this predictive model in this hospitalization sample of adolescents with MDD and suicidal ideation.

Methods:The initial diagnostic classifier was developed in an outpatient sample of adolescents with MDD. 21 adolescents aged 14 to 17 years (F = 17 M = 4) with MDD and 14 healthy controls aged 14 to 17 years (F = 10 M = 4) received a single resting EEG. The Mini International Neuropsychiatric Interview for Children and Adolescents (MINI-KID), the Childhood Depression Rating Scale (CDRS), the Snaith-Hamilton Pleasure Scale (SHAPS) and the Pediatric Anxiety Rating Scale (PARS) were performed.

QEEG was collected in four frequency bands (alpha, beta, theta and delta) and the coherence, cross-correlation and power data streams were obtained. A two-stage analytical framework was then used to develop the final logistic regression model, which was then evaluated using Receiver Operating Characteristic (ROC) curve analysis.

The validation sample consisted of a group of 27 adolescents with MDD aged 13 to 18 years (F = 21 M = 6) admitted to a child psychiatric inpatient unit due to acute suicidal tendencies and 29 CSs aged 13 to 18 years (F = 16 M = 13). 🇧🇷 This cohort received the MINI-KID, the ECCD and the PARS. In addition to task-based data, resting EEG data were also collected from this cohort of adolescents. The diagnostic classifier was validated on resting EEG data collected in this sample. Coherence, cross-correlation and power data streams were obtained in the same four frequency bands.

Results:Within the initial training dataset of outpatients with MDD, 6 qEEG dyads (all consistent) had significant predictive values. The top 10% of the predictive markers used to develop the classifier contained coherence in the following dyads: F3-C3 (alpha frequency (fr)), P3-O1 (theta fr), F3-C3 (theta fr), F3-C3 (beta fr), CZ-PZ (beta fr), Fp2-F4 (theta fr), F3-C3 (delta fr), T8-P8 (beta fr), P3-O1 (alpha fr), Fp2-F4 (alpha fr ) and performance in the following dyads: C3-P3 (alpha fr), T7-P7 (theta fr), F7-T7 (theta fr), Fp1-F7 (alpha fr), F8-T8 (theta fr), P8 - O2 (Theta fr), F3-C3 (Alpha fr), C4-P4 (Delta fr), C4-P4 (Theta fr), P7-O1 (Theta fr), P4-O2 (Beta fr), T8-P8 ( theta fr). Within the final biomarkers, only 4 predictors were used, including F3-C3 alpha coherence (frontal R), P3-O1 theta coherence (parietal R), beta CZ-PZ coherence (central) and P8-O2 theta potencies (parietal occipital) . L) in the final model, which resulted in an area ROC of 0.8226.

In the validation sample of adolescents with MDD and suicidal tendencies, the model that included the top 10% raters returned an ROC of 0.8122. The final model training dataset contained 4 variables, one of which, CZ-PZ, was not available in the validation sample. This model with only the 3 variables common to both datasets gave an ROC of 0.5668. In the validation sample of adolescents with MDD and suicidal tendency, 7 qEEG dyads in adolescents with MDD differed statistically significantly from those with CH (p < 0.05): T8-P8 coherence (beta fr), T8-P8 coherence (theta fr ) , T7 -P7 coherence (beta fr), P3-O1 power (theta fr), F8-T8 power (alpha fr), T8-P8 coherence (alpha fr); Cross correlation E5_E60.

Conclusions:In these two samples of adolescents with MDD, qEEG remains promising as a diagnostic biomarker. A classifier developed on a training set of adolescents with MDD also demonstrated strong predictive value in a validation sample of adolescents with MDD. The extended classifier, which includes a wider range of dyads, performed more robustly than the narrow 4-element classifier. Both groups of participants with MDD show differences in measures of connectivity in the frontal regions, consistent with changes in the default mode network in depressed adolescents.

Future longitudinal studies are needed, particularly in adolescents before starting treatment. In addition, studies are needed that examine how medication, anxiety severity, and anhedonia affect qEEG results. Studies examining the difference between suicidal and non-suicidal adolescents with MDD are also indicated in the future based on this preliminary research.

Key words:Adolescent depression, biomarkers, EEG connectivity

To disclose:Nothing to disclose.

Lu Lu, Maxwell Tallman, Thomas Blom, Kaitlyn Bruns, Jeffrey Welge, Luis Rodrigo Patino, Jeffrey Strawn, Qiyong Gong, John Sweeney, Kyle Hinman, Manpreet Singh, Melissa DelBello*

University of Cincinnati, Cincinnati, Ohio, USA. UU.

Background:Adolescents with a family history of bipolar disorder, particularly those with symptoms of depression and/or anxiety, are at high risk of developing bipolar disorder and impaired functional connectivity (FC) within the emotional network of the prefrontal amygdala. Antidepressants are commonly used to treat teenage depression and anxiety. However, the neural effects of exposure to antidepressants in these high-risk adolescents remain unknown. Our objectives were 1) to compare resting state HR in depressed and/or anxious adolescents at high risk of developing bipolar disorder with healthy adolescents and 2) to compare early changes in resting state HR in these high risk adolescents. treatment with escitalopram and compare psychotherapy vs. placebo and psychotherapy.

Methods:We conducted a double-blind, placebo-controlled, two-site study of escitalopram in adolescents (12-17 years) with depression and/or anxiety and a first-degree relative with bipolar I disorder (BD). At baseline, 121 high-risk adolescents and 55 healthy controls (HC) with no first- or second-degree relatives with a mood or psychotic disorder were recruited. High-risk adolescents were randomized to receive psychotherapy plus escitalopram (n=77) or psychotherapy plus placebo (n=44) for up to 16 weeks.

A 3 Tesla scanner with an 8-channel phased array head coil was used at each site to acquire resting functional and anatomical images at baseline in high-risk and high-risk adolescents and 4 weeks after treatment in high-risk adolescents. high risk. at-risk youth Two 5-min functional runs used TR = 2000 ms and slice thickness = 3 mm. Image analysis was performed using SPM, CONN and MATLAB. Pre-processing steps included discarding the first ten volumes, cutting time, realignment, segmentation and structural normalization, functional normalization, outlier detection and smoothing. Denoising was then performed, which applied linear confounding regression, bandpass filtering, and linear bias reduction to remove unwanted motion, physiological effects, and other artificial effects from the BOLD signal. Next, the HR map was constructed between the amygdala and whole brain voxels for each adolescent, who was then subjected to two second-level statistical analyses: 1) high risk vs. HR HC amygdala-based t-tests with age, sex, and location as covariates using thresholds p<0.005 at voxel level and p<0.05 at group level corrected for false detection rate (FDR) and 2) treatment interactions (escitalopram or placebo) by time (baseline or week 4) below Using full factor analysis with age, sex and location as covariates and using the same thresholds as baseline analyses. Connectivity values ​​were extracted from groups with significant interactions between treatment and time. Post hoc analyzes were performed to estimate the direction of HR changes from baseline to week 4 in each treatment group.

Results:Baseline differences in amygdala-based HR between high-risk and HC adolescents:

Initial analyzes included 106 high-risk adolescents and 46 age- and sex-matched HCs with usable data. Compared to CH, high-risk adolescents had less connectivity between the left amygdala and the left ventral prefrontal cortex, extending to the insula and superior temporal cortex (maximum coordinate: x=-46, y=16 , z =-16; group size = 122; t = 4.78; p = 0.036 corrected for FDR) and decreased connectivity between the right amygdala and bilateral dorsal anterior cingulate cortex (apex coordinate: x = -4, y = 26, z = 14; group size = 217; t = 5.48; p = 0.002 corrected for FDR) and right dorsolateral prefrontal cortex (apex coordinate: x = 22, y = 52, z = 14; group size = 129; t = 4.45; p = 0.014 corrected by FDR) compared with HC .

Effect of escitalopram on amygdala-based HR in high-risk adolescents:

Eighty-four high-risk adolescents with usable baseline and week 4 data were included; 50 of them received escitalopram and 34 received placebo. Significant treatment-dependent interactions were found between the right amygdala and the bilateral supplementary motor cortex (maximum coordinate: x=-2, y=-26, z=62; group size=264; F=20.18; p=0.011 corrected for FDR), left lateral occipital cortex including the left fusiform gyrus (maximum coordinate: x = -44, y = -78, z = 10; group size = 424; F = 16.97; p = 0.001 with correction for FDR) and right occipital fusiform gyrus (maximum coordinate: x = 32, y = -64, z = -6, group size = 197, F = 15.72, p = 0.032 corrected for FDR). Post hoc analyzes showed that these amygdala CCs were significantly decreased in escitalopram-treated adolescents compared to placebo-treated adolescents.

Conclusions:We found that depressed and/or anxious adolescents at high risk for bipolar disorder had reduced amygdala connectivity in regions dedicated to the perception and regulation of emotions compared to healthy subjects. These results suggest that functional brain connectivity within and between emotion processing and regulatory networks is disrupted in adolescents at high risk for bipolar disorder. These alterations can serve as potential targets for early intervention in this population. Furthermore, amygdala connectivity to the sensory and motor cortices was significantly decreased in high-risk adolescents after four weeks of treatment with escitalopram and psychotherapy compared to those who received four weeks of placebo and psychotherapy. Further analysis will examine whether the significant effects of escitalopram at the interface between emotional, visual, and motor networks are related to subsequent behavioral and mood changes resulting from antidepressant treatment in this population.

Key words:Bipolar disorder, high risk, functional connectivity

Divulgações: Myriad, Medscape: Advisory Board (auto), Alkermes: Consultants, Contract Research (auto), Lundbeck, Janssen: Contract Research (auto), Janssen: Consultants (auto), Allergan, Shire: Contract Research (auto)

Kathryn Cullen*, Jessica Butts, Donovan Roediger, Zeynep Basgoze, Bonnie Klimes-Dougan, Bryon Mueller, Kelvin Lim

University of Minnesota School of Medicine, Minneapolis, Minnesota, USA

Background:Adolescence is a critical period for brain development and is also characterized by the occurrence of non-suicidal self-harm (NSSI), a risk factor for future suicide attempts. Examining the brain developmental processes associated with the onset and progression of NSSI during adolescence promises a better understanding of risk mechanisms and guidance for intervention strategies.

Methods:164 adolescents aged 12 to 16 years (assigned female at birth) with and without a history of NSSI were enrolled in a longitudinal study that included annual clinical and imaging evaluations for three years. The frequency and severity of NSSI was assessed using the Self-Injurious Thoughts and Behaviors Interview. Brain imaging included a structural scan, a 12-minute resting-state fMRI, and a six-minute fMRI to measure threat-related response in which participants displayed emotional faces (fear, anger) or neutral shapes. Functional data were plotted using the Glasser atlas for cortical regions and the Harvard-Oxford atlas for subcortical regions. Given the relevance of the persistent threat domain to NSSI, and following our previous work suggesting a relationship between NSSI severity and threat-related circuitry at baseline (Başgöze et al., 2021), brain metrics for the longitudinal analyzes included activation of the amygdala in response to threat. and resting-state functional connectivity (RSFC) between the bilateral amygdala and the ventromedial PFC (vmPFC). In addition to standard methods for calculating RSFC, to further explore neural connectivity and study the direction of neural connections, we use causal discovery analysis to identify causal relationships (edges) between brain regions. Since very few participants had amygdala-related causal boundaries, these analyzes focused on the connections between the main frontal regions involved in emotion regulation (medial and dorsolateral bilateral frontal cortices (mPFC and dlPFC)) as well as the default network (DMN). mode. , which has been linked to depression and self-referential processing. For the task data, we focused on activation in the Emotion>Shape contrast in the bilateral amygdala. For longitudinal analyses, in this NSSI-enriched sample, we first assessed developmental associations in this set of adolescent brain metrics by performing separate regression analyzes for each brain metric using generalized estimating equations (GEEs). to estimate the association of reference age and change age. baseline on connectivity strength. Second, to assess the impact of NSSI behavior on brain development, we added a term for baseline NSSI and the interaction between baseline NSSI (none, mild [1-4 lifetime episodes], moderate [more than 5 episodes and a frequency of at least once a month] and severe [more than 5 episodes in a lifetime and a frequency greater than once a month]) and change in age from onset. Results were considered statistically significant if the two-tailed p-value was less than 0.05. P values ​​were not adjusted for multiple comparisons.

Results:Evaluable clinical and imaging data were available for 140 participants at time 1, 87 participants at time 2, and 39 participants at time 3. Brain metrics (p < 0.05) in models for amygdala activation to threat and threshold DMN causality to the left dlPFC. When examining group effects by time, the course of change over time for the severe NSSI group differed significantly from the non-NSSI group for DMN causal boundaries for left mPFC and right mPFC for DMN. The course of change over time for the moderate NSSI group was significantly different from the no-NSSI group for the DMN causal limits to right mPFC (which also had a main effect of age) and right mPFC to right dlPFC. When examining the severe NSSI group with no significant interaction with age change, the mild NSSI group had significantly weaker connections than the non-NSSI group at the edges of left dlPFC to DMN and left mPFC to left dlPFC. Furthermore, the group with severe NSSI had significantly lower RSFC from the amygdala to the vmPFC (which also had a main effect for age) compared to the group without NSSI.

Conclusions:We report evidence of developmental changes in key circuits relevant to emotion regulation and self-related processing in mid-adolescence. The severity of NSSI in adolescence is associated with neural signatures, some present over time and others manifested as changes over time, which characterize distinct neurodevelopmental trajectories in key circuits. Understanding these patterns is critical to designing and testing new treatments to restore healthy neurodevelopment.

Key words:Brain development, adolescence, non-suicidal self-injury (NSSI)

To disclose:Nothing to disclose.

Rami Al-Haddad, Synthia Guimond, Philippe Robaey, Pedro Rosa-Neto, Clifford Cassidy*

University of Ottawa Mental Health Research Institute, Ottawa, Canada

Background:In recent years, neuromelanin-sensitive magnetic resonance imaging (NM-MRI) has been applied to study the integrity and function of human catecholamine systems in vivo. To optimize the use of the method, it is important to consider the known accumulation of neuromelanin (NM) in the substantia nigra (SN) throughout life, which has shown a great impact on the signal. This is relevant not only in old age, where the method has been frequently applied in the context of neurodegenerative diseases, but also in the first years of life, where the method offers a rare opportunity to directly study the function of the dopaminergic system. context of pediatrics. illnesses. Although previous work has suggested that SN signaling may follow an inverted U-shaped pattern that peaks in middle age and declines somewhat in old age, this paper has not examined the SN in anatomical detail, a level of analysis necessary to optimize the use of the method. for mechanistic studies or as a biomarker it may be necessary.

Methods:NMR MRI images were acquired at two different locations using the same turbo spin echo sequence. Sample 1 was collected at the uOttawa Mental Health Research Institute and included persons aged 7 to 30 (n = 27) and 52 to 82 (n = 22). Sample 2 was collected at the Montreal Neurological Institute and from individuals older than 52 years, all with longitudinal data with 1-2 annual follow-up exams (n = 68). The NM-MRI signal in the SN was probed using a pipeline that brings NM-MRI images into a standardized space and performs intensity normalization relative to a reference region close to the SN with low MN content, the crus cerebri. 🇧🇷 In sample 1, robust voxel-by-voxel linear regression analyzes were performed within the SN to predict the NM-MRI signal as a function of age and sex. In Sample 2, linear regressions were performed on each participant's longitudinal data to determine the slope of change in the NM MRI signal over time for all SN voxels, followed by 1-sample t-tests in you're pending Permutation tests were applied for significance tests.

Results:In order to explain the developmental changes in the SN both at the beginning and at the end of life, we divided sample 1 into those younger than 30 years old and those older than 52 years old. In the younger group, the entire SN showed a significant increase in signal with age (R = 0.63, p = 0.0005, gender-controlled partial correlation) and voxel-by-voxel analysis found a large number of voxels. within the central SN, which increased with age (1000 of 1879 voxels, threshold at p<0.05, adjusted p<0.001, permutation test). The annual signal increase here was 0.24% of the signal in the reference region. Almost none of the SN voxels showed a decreasing signal in this age group (4 voxels). In the elderly, a set of 172 voxels in the central SN showed increasing signal with age (annual variation = 0.19%) and a set of 112 voxels in the peripheral SN showed a decreasing signal with age (annual variation   = -0.21% ).

Examining longitudinally the change in SN signal over time in a separate sample collected at another institute (sample 2, similar in age group to the oldest group in sample 1), there was a large pool of voxels, in which the signal decreased with age. time. time (threshold at p<0.05, 515 voxels, corrected p<<0.0001, permutation test, mean annual change across all subjects = -0.40%) and a small group of voxels where the signal at this threshold increased over time (9 voxels, mean annual change across all subjects = 0.34%). When examining the spatial overlap between SN voxels where the signal changed with age (sample 1, older group) and SN voxels where the signal changed with time (sample 2), both signal voxels increased (corrected S = 0.007, permutation test). ) and decreasing-signal voxels (p < 0.0001 corrected).

Conclusions:We found evidence that the MRI-MRI signal increases relatively quickly along the SN in the first years of life. Even later in life, signaling in part of the central nucleus of the SN continues to increase as the SN appears to decrease in size, possibly due to the loss of dopamine cells during normal aging. These results provide rare insights into the development of the human dopaminergic system. They should support the use of NM-MRI as a biomarker, allowing anatomically detailed age-specific norms for signals within the SN. This is particularly relevant, as the method could have important applications in both young and elderly populations (for example, in pediatric and neurodegenerative diseases). These results are consistent with the significant contribution of NM to contrast, given NM's known tendency to accumulate linearly over its lifetime. Going forward, we will model the developmental change in nuclear magnetic resonance (NM-MRI) signal over a lifetime using an extended longitudinal sample and investigate the impact of other clinical and demographic factors that may need to be considered. potential. the method as a biomarker.

Key words:Dopamine, brain development, neuromelanin-sensitive MRI, healthy subjects, substantia nigra

To disclose:Terran Biosciences: patent, research contract (own)

Eldin Jasarevic*

University of Pittsburgh, Pittsburgh, Maryland, USA. UU.

Background:Circadian rhythms orchestrate a wide range of homeostatic processes, including metabolism, immune function, and two-way communication between the gut and the brain. Emerging evidence suggests that the gut microbiome and its metabolites are a new class of entrainment signals, but the precise molecular mechanisms by which circadian rhythms in microbial metabolites contribute to these processes remain unknown. Furthermore, circadian rhythms are influenced by gender, suggesting that the functioning of the microbiome-gut-brain axis is gender-specific and influenced by the time of day.

Methods:To test the hypothesis that sex differences in the microbiome-gut-brain axis depend on time of day, we used a new systems biology approach, combining longitudinal analyzes with dietary manipulation, metabolomics, bulk transcriptomics, and single manipulation. brain, single cell immunophenotyping and machine learning. We collected tissues from male and female C57Bl/6J and BALB/c mice every 4 hours during the day-night cycle.

Results:Bulk transcriptome analyzes of the intestinal tract showed that the transcriptional signatures were sex-specific and time-of-day dependent (FDR < 0.05). Daily patterns of gene expression in the gut were synchronized with production and peripheral availability of microbial short-chain fatty acids (SCFAs). Integrated unicellular immunophenotyping, metabolomics, and transcriptomics showed that diurnal changes in peripheral SCFA availability were associated with modifications in circulating immune composition and transcriptional signatures in key neuronal regions that control metabolism throughout the body, including the nucleus, the arcuate hypothalamus. These sex-specific diurnal patterns were abolished in germ-free mice, suggesting that an intact gut microbiome is required to synchronize sex differences in the microbiome-gut-brain axis (p<0.05 for all comparisons). Furthermore, SCFA biosynthesis requires the availability of soluble dietary fiber in the diet. To determine whether dietary soluble fiber availability and subsequent SCFA availability is a necessary diurnal sex difference in the microbiome-gut-brain axis, mice were fed a refined high-fat, low-fiber (HFD) diet. . versus a grain-based control (GBC) for six weeks. Diurnal effects on SCFA availability were disturbed in mice consuming HFD, suggesting that dietary soluble fiber availability is essential for diurnal variations in cecal weight and SCFA frequency.

Conclusions:Our results demonstrate that the synchronization of daily dietary patterns with the availability of essential nutrients controls sex differences in the microbiome-gut-brain axis and regulates host immunity and neuroendocrine function. Our results motivate research on the host circadian clock and microbial circadian rhythms and underscore the need to consider gender and sampling time in neuroscience experiments.

Key words:Microbiota-gut-brain axis, immunity and neurodevelopment by gender, immune metabolism, neurometabolism, brain regulation of metabolism

To disclose:Nothing to disclose.

Caroline Smith*, Danielle Rendina, Marcy Kingsbury, Karen Malacon, Dang Nyugen, Jessica Tran, Benjamin Devlin, Madeline Clark, Ravikiran Raju, Lauren Burgett, Staci Bilbo

Duke University, Durham, North Carolina, USA

Background:Epidemiological data suggest that perinatal exposure to environmental toxins, such as air pollution, is associated with the risk of autism spectrum disorders (ASD). Psychosocial stressors can activate the maternal immune system and increase sensitivity to these toxins. However, the mechanisms by which this synergism occurs still need to be elucidated. ASD is male biased and is defined by impairments in social interaction/communication and repetitive/restrictive behaviors. It is important to highlight that the gut-brain axis is also strongly implicated in ASD. Using a novel mouse model of combined prenatal diesel particulate matter (DEP) and maternal stress (MS), we found that post-DEP/MS male offspring exhibit reduced sociability, changes in gut microbiome, and altered microglia and dopaminergic tone .

Methods:First, we wanted to test whether restoration of typical control gut microbiota could save social behavior after DEP/MS through a cross-incentive approach. Male and female pups exposed to DEP/MS were collected on the day of birth from a mother exposed to DEP/MS or CON. Social behavior during adolescence was assessed. Second, we used a chemogenetic approach to test whether activating the dopamine system could save social behavior during adolescence. DAT-Cre+ CON or DEP/MS males received a stereotaxic microinjection of either a control virus or an excitatory DREADD receptor virus into the ventral tegmental area. Clozapine N-oxide was administered before the behavioral test. Finally, we performed RNA sequencing of microglia isolated from male CON and DEP/MS pups and compared gene expression patterns with those of germ-free mice, LPS-stressed mice, and developmentally (based on pooled) mice. previously published data) using range hypergeometry. Overlay Analysis (RRHO).

Results:We found that day-of-birth cleaning of male pups exposed to DEP/MS to CON mothers prevented a decrease in sociability (t(1.13)=3.334, p<0.01). Second, we observed that DREADD activation of VTA dopaminergic neurons restored social preference in male offspring exposed to DEP/MS (F(2,26) = 4.253; p < 0.05). Finally, we found that microglial gene expression patterns in males exposed to DEP/MS corresponded to gene expression signatures in germ-free mice. Interestingly, this was the opposite of comparisons between men exposed to DEP/MS and men treated acutely with LPS.

Conclusions:These results suggest that intervention at the level of the gut microbiome (perinatal) or the dopaminergic system (acute during adolescence) is sufficient to save social functioning after prenatal exposure to DEP/MS in male offspring. Furthermore, our results suggest that DEP/MS induces a microglial phenotype similar to that of germ-free mice, possibly immature and less immunocompetent.

Key words:Autism, air pollution, microglia, dopamine, microbiome

To disclose:Nothing to disclose.

Julia Dziabis*, Caroline Smith, Irene Jonathan, Benjamin Horvath, Marcy Kingsbury, Dang Nyugen, Neil Rogers, Justin Savage, Richa Hanamsagar, Staci Bilbo

Duke University, Durham, North Carolina, USA

Background:Parvalbumin+ interneurons (PVI) are rapidly impaling GABAergic cells and are essential in coordinating firing activity to maintain normal brain function. Developing PVIs are susceptible to inflammation, making them a common cell type affected by disorders such as schizophrenia, autism spectrum disorders, and major depressive disorder. Decades of studies also point to the impact of perinatal inflammation on the function of microglia, the brain's resident immune cells, and their role in synaptic changes and disease-related behaviors in mice. Importantly, microglia interact intimately with developing neurons and affect their maturation and survival. Despite this, almost all existing studies on microglial-neurons interactions in the early postnatal period focus only on excitatory neurons, and very little is still known about microglial-interneurons interactions during development. We hypothesized that extensive ablation of microglial inflammatory signals would protect the development of PVI after immunological challenge in the first years of life. However, loss of microglial inflammatory signaling resulted in increased PVI density in the male brain, suggesting a role for MyD88-dependent microglial signaling in regulating PVI development under basal conditions. Here we intend to investigate the mechanisms linking microglial inflammatory signaling pathways and PVI density in adults.

Methods:Our laboratory has developed a mouse in which the Toll-like receptor adapter protein MyD88 (primary myeloid differentiation response 88) is specifically cleaved by microglia (Cx3cr1-CreBT-MyD88f/f), effectively activating microglial pro-inflammatory signaling. In adulthood, we characterize whole-brain social and cognitive behaviors and PIVs using immunohistochemistry. To investigate the role of MyD88 microglial signaling in early PVI development, we used RNAscope to identify future PVI prior to parvalbumin protein expression. Finally, changes in PVI synapse density during wild-type development were determined by co-labeling of PVI-specific presynaptic tag synaptotagmin-2 (Syt2) and postsynaptic tag gephyrin, which was quantified using software developed by the Eroglu Lab at Duke University.

Results:We found that microglial loss of MyD88 had a significant impact on PVI density in the hippocampus (F(1,37) = 5.54, p = 0.024; n = 6-12/group) and frontal cortex in men. (F(1, 10) = 10.82, p = 0.0082; n = 3-5/group), but not women (F(1,12) = 0.01774, p = 0.8963; n = 3-5/group). The MyD88 microglial genotype had no significant effect on somatostatin interneuron density (SST), another common subtype of interneurons, in the frontal cortex of men (F(1,13) = 1.578, p = 0.231; n = 3 -5/group ) or women (F(1,13) = 0.746, p = 0.404; n = 3-5/group). Mice lacking microglial MyD88 signaling have normal sociability at baseline (male: F(1,33) = 0.321, p = 0.575; female: F(1,31) = 1.659, p = 0.207; n = 8-10 /group ), but men show reduced spatial reference memory in a Y-maze task (t(1.22) = 2.591, p = 0.0167; n = 12/group). We then hypothesized that loss of microglial MyD88 affects the development of adult PVI density. Preliminary results suggest that microglial loss of MyD88 does not affect the early postnatal period of P0-P8 cell death of PVI development in the male dorsal hippocampus (F(1,11) = 0.1723, p = 0.6861; n = 2-4/group). Wild-type characterization of male and female PVI P4-P42 cell density revealed no sex differences (F(1,32) = 0.2732, p = 0.6048; n = 2-5/group), but males have a higher density of PVI synapses in the third postnatal week (F(1,42) = 46.43, p<0.0001; n=4-7/group), a possible mechanism by which PVI synapse density PVI is regulated by sex in adults. Ongoing work will characterize synaptic deletion by wild-type and MyD88-deficient microglia in males and females during the PVI synaptic pruning period to attempt to identify a sensitive time window of PVI density regulation in males.

Conclusions:Microglia regulate PVI development in the male frontal cortex and dorsal hippocampus initially in a MyD88-dependent manner, with consequences for adult cognition. The early postnatal period of PVI cell death is not altered by loss of microglial MyD88, suggesting that microglial regulation of adult PVI population size occurs after the first postnatal week. Future work will investigate microglial phagocytosis of PVI synapses in early adolescence.

Key words:Microglia, neurodevelopment, parvalbumin interneurons, Toll-like receptors (TLRs), cognition

To disclose:Nothing to disclose.

Sohye Kim*, Jean Frazier, David Cochran, Isha Jalnapurkar, Kyle Roell, Stephen Hooper, Peter Fonagy, Hudson Santos, Robert Joseph, Karl Kuban, Semsa Gogcu, Rebecca Fry, T. Michael O'Shea

University of Massachusetts School of Medicine, Worcester, Massachusetts, USA.

Background:Adolescent depression is an important public health problem, with an estimated prevalence of 14% for major depressive disorder (MDD) between the ages of 15 and 18 years. About 84% of depressed teens develop depression later in adulthood. Despite the devastating clinical consequences of juvenile MDD, its etiology and pathophysiology remain poorly understood.

A growing body of data supports a possible role for inflammation in the pathogenesis of depression, although it is unclear whether inflammation is a cause, correlate, and/or consequence of MDD. A recent meta-analysis has shown that elevations in inflammatory biomarkers, particularly interleukin-6 (IL-6) and C-reactive protein (CRP), may precede the onset of depression. However, the prospective studies available to date have mainly focused on adults and the elderly, with the strongest associations between inflammation and depression seen in geriatric samples. Little is known about longitudinal associations in pediatric samples and, to date, no studies have examined the role of early childhood inflammation (ELI) in later depression. A systematic understanding of how the ELI interacts with known risk and protective factors for depression is also lacking.

In the present study, we examined a longitudinal association between ELI determined during the neonatal period and depression at age 15 years in a cohort of adolescents who were born extremely preterm. Extremely preterm infants are at high risk of developing neonatal inflammation and subsequently developing psychiatric disorders, including depression in adolescence. Therefore, extremely preterm infants are an ideal group to investigate these associations. We hypothesize that (1) ELI will be associated with an increased risk of depression at age 15, (2) childhood adversity, a well-documented risk factor for depression, will increase the risk of ELI in depression, and (3) social support, a well-documented protective factor for depression, will mitigate the risk of ILI in depression.

Methods:The Extremely Low Gestational Age Newborns Study (ELGAN) is a multicenter longitudinal study of infants born <28 weeks of gestation. We measured six circulating inflammatory proteins (ie, interleukin-6 [IL-6], tumor necrosis factor alpha [TNF-α], intercellular adhesion molecule-1 [ICAM-1], interleukin-8 [IL-8], serum) . amyloid A [SAA] and C-reactive protein [CRP]) in 1,121 extremely preterm infants on days 1, 7, and 14 postpartum. These proteins were chosen based on their consistent associations with structural and/or functional neurological outcomes in previous ELGAN studies. For each protein, we defined intermittent/sustained systemic inflammation (ISSI) as values ​​in the top quartile within the gestational age stratum at ≥2 days during the first 14 days after birth. At age 15, 670 adolescent survivors (344 males and 326 females) were assessed for depression using the Child Behavior Checklist (CBCL) and PROMIS Depression Scale, and for a diagnosis of MDD using the International Neuropsychiatric Mini Interview. for Children and Adolescents (MINI FILHO). We used linear regression and multiple logistic models to examine the association between the number of ISSI proteins (0, 1-2, or ≥3 elevations) and depression at age 15 years. The moderators evaluated were childhood adversity, measured by the Yale-Vermont Adversity Scale, and adolescent social support, measured by the PROMIS Family and Peer Relations scales. Analyzes were stratified by adolescent sex and adjusted for confounders determined by directed acyclic plots, including family history of depression and noninfectious triggers of neonatal inflammation (i.e., small for gestational age, low maternal socioeconomic status, prenatal exposure to maternal smoking, maternal obesity and maternal hypertension). Associations were expressed as odds ratio (OR) and 95% confidence intervals (CI). For continuous results, effect sizes were expressed as regression coefficients that quantify the difference in depression T-scores for participants with and without exposure.

Results:In our sample of extremely preterm infants, elevated ELI protein levels were not significantly associated with the diagnosis of MDD (ISSI 1-2: OR = 1.30, 95% CI = 0.75-2.22; ISSI ≥ 3: OR = 0.89, 95% CI = 0.42 -1.82) or CBCL/PROMIS depression scores at age 15 (ISSI 1-2: βs -0.88 to 0.01; ISSI ≥3: βs - 1.64 to -1.17). As expected, childhood distress was positive with diagnosis of adolescent MDD (OR = 1.13, 95% CI = 1.08-1.18) and CBCL/PROMIS depression scores (βs 0.21 to 0.49) associated, whereas social support in adolescents was negatively associated with diagnostic MDD (OR=0.91, 95% CI=0.86-0.96) and depression scores (βs -0.38 to -0.69). However, the proposed moderators did not significantly interact with the ELI to predict adolescent depression at age 15.

Conclusions:We found no significant associations between neonatal systemic inflammation and depression measured at 15 years of age. Future research is needed to determine whether individual levels of inflammatory proteins or the timing of inflammation are better predictors of depression onset.

Key words:Inflammation, neonatal, adolescent depression, biomarkers

To disclose:Nothing to disclose.

Justin Russell*, Sara Heyn, Ryan Herringa

University of Wisconsin, Madison, Wisconsin, USA

Background:More than a billion children around the world are at risk of suffering the chronic and widespread consequences of experiences so harmful that they are called "adversities", circumstances or events that threaten physical or psychological well-being. The constellated biological and psychological effects of negative experiences predict chronic increases in the risk of mental illness, poverty, addiction, crime, morbidity, mortality, suicidal tendencies, and most importantly, ongoing adversity for others. Traumatic and early life experiences (TRACES; Weems et al., 2021) are the greatest preventable risk factor for psychopathology and cost the United States an annual economic cost ($748 billion) that exceeds the annual economic output of nine out of every ten nations around the world. globe.

While decades of research demonstrate the link between adversity and chronic dysfunction, the nature of adversity as a concept remains a matter of heated debate, with competing models emphasizing the importance of discrete features (Smith & Pollak, 2020) or two-dimensional features (McLaughlin et al. ., 2020) when recording the neurological consequences of behavior. Current work proposes a unifying reconceptualization of adversity as a multidimensional concept composed of groups of thematically related events that are likely to have shared downstream impacts. A new data-driven approach is applied to reported exposure of adolescents to over 100 different experiences, reflecting different forms of adversity that perpetuate maladjustment. These data were reduced to dimensional components of TRACES and considered predictors of state and maturational change in the presence of psychiatric symptoms and cognitive development.

Methods:The analyzes extracted data from 11,876 adolescents (aged 9 to 10 years; 51% female) and their caregivers who participated in the baseline (year 0) collection of the Adolescent Brain Cognitive Development (ABCD) study, from 11,225 dyads who completed the assessment repeated in ABCD Year 1, 10,414 in ABCD Year 2, and 6,251 in Year 3. Fluid intelligence was put into play as a latent factor derived from age-adjusted standardized scores obtained from relevant tests included in an abbreviated administration of the NIH Toolbox ( Y0,Y2). 🇧🇷 The internalizing and externalizing issues were put into practice using the summary results from the ASEBA Child Behavior Checklist Categorical Leads Report collected at each wave of data collection (Y0-Y3). A comprehensive review of assessment tools conducted in Year 2 (Y2) identified 106 youth or parent questionnaire items that capture exposure to negative experiences. For items presented in multiple waves, the most recent data were used, while scores for repeated items in the caregiver's and child's reports were combined taking the highest value. The resulting list contained binary, ordinal, countable, and continuous elements. Categorical Principal Component Analysis (CATPCA) can adequately model each of these types of items (unlike traditional PCA), is resistant to non-normality, and reduces items to formative composites.

Latent averages (fluid intelligence) and path estimates (externalization, internalization, impact of adversity components) reflecting change were derived from models containing temporal measurement invariance. Component scores were calculated and entered as predictors of covariates into separate developmental and baseline change latent difference scoring models on internalizing and externalizing problems and fluid intelligence.

Results:An eight-component solution showed the best fit to the data and the most intuitive interpretation, and included dimensions that reflected caregiver issues (e.g., incarceration, addiction, mental illness), community violence, peer bullying/aggression, chronic pain, poverty, discrimination, family conflicts and interpersonal violence. On average, ABCD teens showed an increase in fluid intelligence [α = 1.63 (SE = 0.18), Z = 9.01, p < .001), no change in externalizing problems, and an annual decrease in externalizing problems. of internalization [ β = -0.11 ( 0.016), p<0.001]. All components of adversity, with the exception of peer bullying/aggression (β = 0.01, p = 0.42), were associated with greater externalizing problems at baseline (all p < 0.05), while community violence increased over time. The predicted outsourcing problems [ β = 0.019 (0.008), p < 0.05]. Caregiver problems, community violence, peer bullying/aggression, discrimination, and family conflict predicted higher levels of problem internalization at baseline (all p < .001), while caregiver problems (p < .05), violence in the community, chronic pain, anticipated discrimination, and family conflicts have been associated with increased internalizing problems over time.

Conclusions:The results demonstrate the viability of an alternative conceptualization of traumatic and adverse childhood experiences, as well as the usefulness of considering the components of a dimensional model as predictors of altered maturational changes in cognitive abilities and psychiatric problems. The results presented will further examine the moderating effects of race, ethnicity, and gender at birth. Overall, this work demonstrates the merits of a multidimensional model that can improve our collective ability to make sense of negative experiences by sculpting nature at its joints.

Key words:Childhood adversity, childhood psychiatric symptoms, statistical methods, study of the adolescent brain and cognitive development, longitudinal analysis

To disclose:Nothing to disclose.

Joan Busner*, Eric Youngstrom, David Daniel, Joshua Langfus, Robert Findling

Signant Health, Virginia Commonwealth University, Avondale, Pensilvânia, EE. UU.

Background:Global regulatory initiatives have led to an increasing number of psychopharmacological studies in the pediatric population. Challenges to ensuring valid and reliable data in such studies include developmental limitations in describing symptoms, the need to integrate and weigh information from multiple sources (including patients, parents/carers and other informants), and the general lack of Dice. of clinically trained children. researchers (Busner, 2013; Farchione, 2013). Furthermore, few efficacy measures have been developed and validated specifically for pediatric studies. As a result, measures developed and validated for adults, such as the Positive and Negative Syndrome Scale (PANSS), are commonly used in studies of schizophrenia in adolescents. The PANSS is a complex 30-item measure that has been extensively studied and has proven difficult to assess even in the adult patients for whom it was designed (eg, Daniel & Dries, 2013). Our group developed a 10-point PANSS based on psychometric analyzes of data from the NIMH-TEOSS study. The 10-point PANSS was reliable and sensitive to changes in treatment. In the present study, we attempted to corroborate the results using an independent study to replicate multiples (Findling et al., in press).

Will a 10-point PANSS optimized for pediatric studies perform similarly to the 30-point PANSS in an independent, multi-site, placebo-controlled study?

Methods:Parallel-group, double-blind, 6-week acute-phase data from the Johnson and Johnson-sponsored complete positive paliperidone study (Singh et al., 2011) were accessed through the YODA secure data environment. The study involved 201 youth aged 12 to 17 who were randomly assigned to receive either a placebo or one of three fixed doses of paliperidone. Analyzes were performed with the mirt, lavaan, sjstat, rstatix ​​and psych packages in R, using the same syntax and methods as the previous analyzes (Findling et al., in press), with mixed regressions to follow using random intersections and squares Partial eta as estimation of effect size for effects of time, treatment, and time x treatment interaction.

Results:The 10-item versus the 30-item versions had mean correlations between like items (0.25 and 0.25) as well as similar partial eta-square values ​​for time: 0.37 (0.32 to 0.41) versus 0.41 (0.36 to 0.45). ), treatment (all 0.00) and time x treatment (0.007 versus 0.003 for total length). The IRT models showed similar reliability to the development sample with good accuracy over a similar range of severity. LOCF analyzes revealed placebo split using the 10-point and 30-point versions in multiple identical arms; ANCOVAs controlling for PANSS at the beginning of the phase generated similar eta-squares in subsequent weeks (major difference  = 0.005, preferred 10-item version).

Conclusions:The 10-item version of the PANSS has been well replicated in a larger, independent sample of adolescents using double-blind RCT data. The similar sensitivity to treatment effects is particularly promising, given the significant reduction in scale length and the corresponding reduction in rater training required, interview duration, and respondent load.

Key words:Child psychopharmacology, clinical outcome evaluations, pediatric clinical trials

To disclose:Signant Health: Shares/Equity (Own)

Wan-Ling Tseng*, Reut Naim, Amanda Chue, Ashley Smith, Shannon Shaughnessy, Daniel Pine, Ellen Leibenluft, Katharina Kircanski, Melissa Brotman

Yale Child Study Center, Yale University School of Medicine, New Haven, Connecticut, EUA.

Background:Irritability, an increased susceptibility to anger compared to peers, is a transdiagnostic symptom commonly associated with anxiety and other mood symptoms. However, little is known about the temporal and dynamic interaction between clinical phenomena related to irritability. Network analysis has the potential to improve our understanding of this complex organization of symptoms and related constructs. In contrast to traditional conceptualizations of psychopathology, which assume that symptoms are manifestations of an underlying, latent cause or disorder, network approaches conceptualize disorders as causally connected, interacting, and mutually reinforcing systems of symptoms (Borsboom and Cramer, 2013 ; Borsboom et al., 2021). Therefore, network approaches are appropriate for revealing patterns of interrelationships between irritability symptoms and behavioral, cognitive, and mood constructs. A better understanding of the temporal dynamics between irritability symptoms can inform the goals and timing of interventions. Using smartphone-based instant ecological assessment (EMA) network analysis to increase ecological validity, this study examined how daily symptoms of irritability and other symptoms of mood and anxiety are related. This is the first study using network analysis to examine irritability symptomatology in naturalistic environments.

Methods:The sample included 152 adolescents aged 8 to 18 years (age: M ± SD = 12.28 ± 2.53; 69.70% male; 65.80% white/Caucasian, 9.90% African American, 4 .60% Asian, 2.60% Native American, 13.20% Multiracial, 3.90% Unknown) into various diagnostic/phenotypic groups enriched for irritability symptoms. Groups included disruptive mood dysregulation disorder (DMDD; n=34), subthreshold DMDD (i.e., those with impaired irritability but who did not meet full DMDD criteria; n=22), attention-deficit/hyperactivity disorder (n=35), anxiety (n=28) and healthy comparisons (n=33). Participants completed the EMA three times a day for seven days (i.e. 21 data points per participant). The EMA items included irritability and related symptoms (bad mood/bad temper, irritation/anger, frustration, feelings of injustice), as well as other mood and anxiety symptoms (worry, happiness, sadness, mood lability). , samples from different affective times (current symptoms versus longer-lasting symptoms). Irritability was also assessed using parent, child, and physician reports of the Affective Reactivity Index (ARI). Network analysis using the multilevel vector autoregressive model (mlVAR) with EMA data estimated three networks: (1) temporal network, (2) concurrent network within subjects, and (3) symptom network among subjects. To further assess whether and how EMA measures of irritability and related symptoms/constructs were associated with "trait-like" measures of irritability based on rating scales, we examined mean level and variability (i.e., SD and mean square root of consecutive differences). [RMSSD]) of EMA-assessed irritability (i.e., four items: moodiness/abuse, irritation/anger, frustration, feelings of injustice) on 21 data points and their correlations with reports from clinicians, children, and parents based on the gold standard of irritability (i.e. ARI).

Results:Frustration was identified as the most central node in the network of symptoms/constructs of irritability (eg, complaining, unfairness) and other mood and anxiety symptoms (eg, mood swings, worrying). Frustration in one moment also predicted positive mood swings in the next. Furthermore, we found differences and similarities in intra-subject and inter-subject processes between constructs/symptoms related to irritability and other symptoms of anxiety and mood. While anger/rage was positively associated with dissatisfaction/sadness between individuals and on measurement occasions, anger/rage was positively associated with dissatisfaction/sadness, instability of the state of mind and concern between/about people. Finally, compared to variability (ie, SD and RMSSD; r's = .13–0.41), mean level of EMA-indexed irritability-related constructs was more strongly associated with retrospective "trait-like" measures of irritability (ie IRA ) ;r's = .23– .56).

Conclusions:This study advances our understanding of the level of symptoms and temporal dynamics of irritability. Frustration was considered the most central node in the network of irritability symptoms/constructs and other mood and anxiety symptoms. Frustration also predicted increased mood swings later in life. These findings have potential clinical implications, suggesting that frustration may be a primary treatment target for adolescents with irritability. Future experimental work or clinical studies are needed to systematically manipulate irritability traits (e.g., frustration, unfairness) to better understand causal relationships between clinical variables. For example, clinical trials can be designed to test the effectiveness of interventions/treatments that target frustration due to their high centrality. Once the causal effect of frustration on other mood symptoms has been validated, using EMA, interventions can be designed and implemented when adolescents become frustrated and before frustration affects other mood symptoms, in a downward direction, in order to intervene in in a timely manner and with maximum efficiency.

Key words:Pediatric irritability, frustration, ecological snapshot, network analysis

To disclose:Nothing to disclose.

Julianne Tirpak*, Emma Cho, Josephine Au, Jillian Russo, Courtney Kaplan, Maria Naclerio, Eileen Lee, Angela Salisbury, Camille Nommi, Daniel Dickstein

McLean Hospital, Harvard Medical School, Belmont, Massachusetts, EUA.

Background:Suicide is the second leading cause of death in children and young adults (Eaton et al., 2005). However, completed suicides represent only a portion of adolescents who experience suicidal behavior. Nationally, more than 16% of high school students seriously consider suicide and more than 8% attempt suicide each year. Additionally, non-suicidal self-harm (NSSI), defined as the intentional destruction of the body's own tissues without the intent to kill, is strongly associated with attempted suicide (SA) in adolescents (Scott et al., 2015; Stewart et al. . . ., 2017). Interpersonal dysfunction is among the strongest predictors of the development and maintenance of NSSI and suicide attempts in this age group (King & Merchant, 2008), but it is a complex and multifaceted construct. The purpose of this study is to better understand which components of interpersonal functioning in adolescents lead to NSSI vs. SA. We hypothesized that higher levels of interpersonal sensitivity and deficits in social problem-solving strategies would be observed in the NSSI and SA groups, but not in healthy controls.

Methods:This IRB-approved study compared the Interpersonal Sensitivity Measure (IPSM), the Social Problem Solving Inventory (PSSI), and suicidal ideation (measured using the Beck Suicide Scale [BSS]) among three relatively mutually exclusive groups. 17) who: (1) engaged in NSSI with no history of AS (n = 50, Mage = 15.35, SD = 1.34, 82% female), (2) did SA with no history of NSSI (n = 49 , Mage = 15.80, SD=1.23, 63% female) and (3) typically developing controls (TDC) with no history of psychopathology (n=43, Mage=15.46, SD=1.30, 61 % women). The analysis strategy included: (1) ANOVA to assess between-group differences in IPSM, SPSI, and BSS, (2) MANOVA to examine possible group and gender differences in IPSM and SPSI, and (3) logistic regression to determine the effects of IPSM and SPSI scores on group status.

Results:ANOVA results indicate significant differences between groups in IPSM (F(2139) = 34.89, p<0.001) and SPSI (F(2139) = 42.5, p<0.001). Tukey's post hoc tests revealed that the NSSI (100.25 ± 18.1, p < 0.001) and SA (84.50 ± 18.50, p = 0.001) groups showed significantly greater interpersonal sensitivity than the TDC (72 .0 ± 10.40). The NSSI group scores were significantly higher than the SA group scores (p < 0.001). For social problem solving, the NSSI group (44.00 ± 14.90, p < 0.001) and the SA group (50.60 ± 17.90, p < 0.001) obtained significantly lower scores than the DCD group ( 71.90 ± 11.00); however, there was no significant difference between the NSSI and SA groups (p = 0.07). Likewise, there was no significant difference in suicidal ideation (SI) between the NSSI and SA groups, t(97)=1.70, p=0.093. SI was not reported in any participant in the DCD group.

A 3X2 MANOVA did not show a significant interaction effect of biological and group sex differences on IPSM and SPSI total scores. The overall MANOVA model for the group was significant [F(4,270) = 21.04, p<0.001]. Univariate analyzes showed significant group effects for IPSM [F(2,136) = 25.23, p<0.001] and SPSI [F(2,136) = 34.06, p<0.001] overall scores. In particular, the NSSI-IPSM mean [MNSSI =99.95] was significantly higher than the TDC mean [MTDC =71.72, p<0.001, Cohen's d =10.04] and the SA mean [ MSA =84.00, p<0.001, Cohen's d=9]. The mean total IPSM score of the SA group was also significantly higher than the mean total score of the TDC group [p = 0.002, Cohen's d = 4.90]. The TDC-PSSI mean [MSPSI =71.60] was significantly higher than the NSSI group mean [MNSSI =44.22, p<0.001, Cohen's d =10.60] and the SA group mean [MSA = 50 .22, p<0.001, Cohen's d 2.9]. There was no significant difference between the mean SPSI values ​​of the SA group and the NSSI group.

The logistic regression model was statistically significant, χ2(2) = 17.027, p<0.001. The model explained 21.1% of the variance (Nagelkerke R2) in group membership and correctly classified 66.7% of cases, demonstrating that higher levels of interpersonal sensitivity were associated with a greater likelihood of adolescents receiving only NSSI. Higher levels of social problem solving were not significantly associated with membership in the NSSI or SA group.

Conclusions:Our results suggest that greater interpersonal sensitivity is clearly associated with adolescents' likelihood to participate in the NSSI but not the SA. Such findings are consistent with existing research frameworks that emphasize interpersonal factors such as sensitivity to rejection in NSSI development and maintenance (eg, the four-function model of NSSI). This study may inform future research using multimodal and longitudinal assessments (eg, behavioral tasks, imaging, genetic mediators, etc.) to examine and assess different facets of interpersonal functioning to better assess unique interpersonal risk factors for suicide. teenagers. Ultimately, a better understanding of interpersonal dysfunction may lead to an assessment of whether current first-line psychosocial treatments for suicidal adolescents directly target these constructs.

Key words:Suicide attempt, non-suicidal self-harm (NSSI), social factors and functioning, severity of suicidal behavior, self-harm

To disclose:Nothing to disclose.

Robyn Wiseman*, Peter Barker, William Clarke, Kristin Bigos

Johns Hopkins School of Medicine, Baltimore, Maryland, USA. UU.

Background:Attention Deficit Hyperactivity Disorder (ADHD) affects a significant number of adult patients, and a small percentage receive an accurate diagnosis and/or adequate treatment. The aim of this double-blind, placebo-controlled crossover study was to identify ADHD-related signatures in the brains of adult patients and to investigate how brain activity, metabolites and cognitive performance are altered by the commonly prescribed stimulant methylphenidate.

Methods:All 7 participants were between 20 and 36 years old, were non-smokers, were right-handed, did not actively take stimulants, and did not have other axis 1 psychiatric disorders. We combined 3T task-based functional magnetic resonance imaging (fMRI) with 7T functional magnetic resonance imaging - resolution MRI. resonance spectroscopy (MRS) to determine the examined brain activity or brain chemistry. Two main fMRI tasks were used: the N-back working memory task and the flanker attention task to assess response inhibition. A standard cognitive battery, including the NIH Toolbox Cognitive Battery, was administered along with the Connors Adult ADHD Rating Scale (CAARS), a self-report survey of ADHD symptoms.

Results:As expected, methylphenidate levels were correlated with frontal cortical activity during working memory (p=9.9e10-5, slope=0.08073 r2=0.932). The ADHD index, a CAARS measure of symptom severity, was sensitive to a single dose of methylphenidate (p=0.021), and drug concentration was positively correlated with frontal cortex activity during working memory (p=0.021 ). =0.0227, slope=6.165, r2). = 0.6067). Elevated levels of glutamate in the anterior cingulate cortex and dorsolateral prefrontal cortex (dlPFC) were associated with positive changes in the composite cognitive function score (p = 0.0047, slope = 30.89, r2 = 0.95) and score fluent cognitive composite (p = 0.0066, slope) connected = 18.91, r2 = 0.94). We also observed negative correlations between age and processing speed (p=0.0171, slope=-2.266, r2=0.8852, uncorrected values) and dlPFC-glutamate values ​​(p=0.0339, slope=-0.091) , r2=0.82).

Conclusions:The novelty of this study lies in the combination of approaches used to study the neural pharmacology of ADHD. By combining functional measurements with high-resolution spectra of important brain metabolites and cognitive data, we created a more complete picture of how stimulants affect the brains of people with ADHD. The fact that we were able to detect significant, synchronous changes in cortical activity and glutamate levels suggests that multimodal brain imaging may be a viable, non-invasive tool for ADHD drug development.

Key words:ADHS, fMRI, 7T MRS, metilfenidato

To disclose:Nothing to disclose.

Brittney Yegla*, Jennie Garcia-Olivares, David Zweibaum, Frank Bymaster, Chungping Yu

Supernus Pharmaceuticals Inc., Rockville, Maryland, EE. UU.

Background:Viloxazine ER (viloxazine extended-release (ER) capsules; Qelbree®), an FDA-approved nonstimulant medication for attention-deficit/hyperactivity disorder (ADHD) in adults and children (≥6 years), is pharmacologically distinct from other approved treatments. Most FDA-approved ADHD treatments share a primary mechanism of increasing levels of norepinephrine (NE) and/or dopamine (DA). Viloxazine increases NE, but is only a weak norepinephrine (NE) reuptake inhibitor (IC50 = 0.3 μM in human NE transporters) and has been shown to have moderate activity at serotonin (5-HT) receptors. Previous in vivo microdialysis experiments with viloxazine showed large increases in NE, DA and 5-HT in the prefrontal cortex (PFC) of rats. As the PFC is associated with the pathophysiology and attentional control of ADHD, elevations of monoamines (5HT, DA, and NE) in this domain may be critical to the therapeutic effects of viloxazine. However, the dose of viloxazine used in these previous microdialysis experiments (50 mg/kg, ip, rat) resulted in brain concentrations of unbound viloxazine higher than the estimated unbound concentration in the plasma of pediatric ADHD patients, than in clinical trials received viloxazine 400 mg ER / day. Consequently, the current microdialysis study was undertaken to further investigate the dose-dependent effects of viloxazine on prefrontal monoamine concentrations in therapeutically relevant concentrations of Qelbree for ADHD.

Methods:Freely mobile Sprague-Dawley rats (male, 8 weeks old, 5-6/group) were implanted with I-shaped microdialysis tubes in the PFC. After recovery from surgery, rat electrodes were connected to a microperfusion pump perfusing artificial CSF containing 147 mM NaCl, 3.0 mM KCl, 1.2 mM CaCl2, and 1.2 mM MgCl2. After establishing a 2-hour baseline, viloxazine (1, 3, 10, or 30 mg/kg) was administered (ip). Dialysate samples were collected from the PFC interstitial fluid (ISF) and measured at 30-minute intervals for the 2-hour and 4-hour baseline periods following viloxazine administration. Dialysate samples were analyzed by LC-MS/MS to determine viloxazine concentration and viloxazine-induced changes in NE, DA, 5-HT and their respective metabolites, 3,5-dihydroxyphenylglycine (DHPG) and 5-hydroxyindoleacetic acid. (5-HIAA) and the precursor 3,4-dihydroxyphenylalanine (L-DOPA). Plasma samples were collected 30 and 90 minutes after dosing to determine corresponding plasma concentrations of viloxazine.

Animal experiments were performed at Charles River Laboratories (South San Francisco, CA, USA) and were performed in accordance with the Guide for the Care and Use of Laboratory Animals (National Research Council 2011). The experiments were carried out according to the US19002 protocol approved by the local Animal Care and Use Committee.

Results:Pharmacokinetic evaluation showed a dose-dependent increase in plasma and ISF concentrations of viloxazine. Plasma concentrations 30 minutes after dosing were 2.4 ± 1.0 µM and 5.7 ± 3.6 µM for doses of 10 and 30 mg/kg, respectively, resulting in calculated free viloxazine plasma concentrations. ~0.9 and ~2.4 µM (based on previous murine studies showing that viloxazine is 40% non-binding to plasma proteins). Determination of viloxazine concentration in the ISF dialysate in PFC showed that the Tmax of viloxazine occurred after 60 min, with Cmax of 1.2 ± 0.3 µM and 3.5 ± 1.6 µM for viloxazine doses 10 and 30 mg/kg, respectively.

Administration of viloxazine resulted in significant dose-dependent effects on interstitial NE levels at all doses tested. Analysis of study results showed that viloxazine-treated animals had significantly higher interstitial NE levels than vehicle-treated animals at t = 60 min, and the 30 mg/kg dose continued to show an increase in NE at comparison with the vehicle until t = 180 minutes. The increase in interstitial NE levels at 60 minutes reached 236%, 418% and 558% above baseline for the 3, 10 and 30 mg/kg dose groups, respectively. Dose-dependent decreases in interstitial concentrations of DHPG (NE metabolite) corresponded to interstitial increases in NE, reflecting the mechanical activity of viloxazine as a NET inhibitor. Viloxazine treatment also resulted in a dose-dependent increase in interstitial 5-HT PFC levels. Following the 30 mg/kg dose of viloxazine, 5-HT elevations reached 213% above baseline at a Tmax of 60 minutes and were also greater than in the vehicle group; however, the absence of concomitant changes in interstitial concentrations of 5-HIAA (5-HT metabolite) again confirmed the lack of activity of viloxazine as a 5-HT reuptake inhibitor.

Conclusions:Viloxazine-mediated interstitial increases in NE and 5-HT were directly related to interstitial viloxazine concentrations, showing a clear pharmacokinetic/pharmacodynamic relationship in the PFC, a critical target region for therapeutic action in ADHD. These results contribute to our understanding of viloxazine's mechanism of action and demonstrate that viloxazine increases PFC interstitial monoamine levels at free plasma concentrations produced by clinically effective doses of viloxazine ER. Therefore, the induction of noradrenergic and serotonergic activity in the PFC may be associated with the therapeutic effects of viloxazine ER in the treatment of pediatric and adult patients with ADHD.

Key words:ADHD, serotonin, microdialysis, viloxazine, PFC

To disclose:Supernus Pharmaceuticals Inc.: Employees (himself)

Aqilah McCane*, Bita Moghaddam

Oregon Health and Science University, Portland, Oregon, EUA

Background:Puberty is a sensitive phase of development. The neural rationale for this vulnerability is poorly understood, but has been attributed to an immature frontal cortex and its connections to the striatum and other subcortical areas that modulate action selection. We observed that action-directed reward processing by neurons in the lateral orbitofrontal cortex (OFC) and dorsomedial striatum (DMS) differs between adolescents and adults. Here, we tested the specific hypothesis that action-outcome associations and response inhibition are processed differently in DMS-OFC ​​circuits in adolescents than in adults.

Methods:We used a signaled response inhibition task (CRIT) to assess response inhibition in adult or juvenile male and female mice. To characterize the role of OFC projections to DMS in adults and adolescents in CRIT, we used DREADD to inhibit OFC neurons that project DMS. Furthermore, we simultaneously recorded individual units and local field potentials (LFPs) in OFC and DMS from juvenile and adult rats performing CRIT. Neural data were analyzed using multiple computational approaches to study the interaction and synchronicity between two brain regions during specific behavioral events. A mixed design analysis of variance (ANOVA) was performed for all dependent variables with the grouping factors of sex and age.

Results:Compared to adults, adolescents give more premature answers and fewer correct answers on the CRIT. We found that inhibition of OFC->DMS projections decreases correct responses and increases premature responses during CRIT, suggesting that this pathway is necessary for the successful performance of response inhibition. Adolescents show a reduced response to the presentation of inhibitory cues in the OFC and an enhanced response to the reward in the DMS. COF peak variability in adolescents was also increased during the presentation of inhibitory cues. Finally, adolescents show reduced OFC and DMS theta performance and reduced OFC-DMS theta synchrony during reward.

Conclusions:These results show that, although the OFC-DMS circuit is critical for response inhibition in adults and adolescents, adolescents activate this circuit differently, being more attuned to rewards and weaker to cues and actions. These data add to our knowledge of how the adolescent brain controls behavior differently compared to adults and highlights the importance of the OFC-DMS circuit in mediating adolescent response inhibition.

Key words:In vivo electrophysiology, corticostriatal circulation, neurodevelopmental disorders, local field potentials, childhood schizophrenia

To disclose:Nothing to disclose.

Cassandra Klune, Caitlin Goodpaster, Rita Chen, Nico Jones, Laura DeNardo*

University of California Los Angeles, Los Angeles, California, USA

Background:The medial prefrontal cortex (mPFC) plays a key role in assessing and responding to threats. In the prelimbic (PL) subregion of the mPFC, the coordinated activity of output circuits directed to the basolateral amygdala (BLA) and nucleus accumbens (NAc) determines whether animals approach or avoid threatening stimuli. Developmentally, as animals reach independence from caretakers, LP circuits undergo prolonged maturation. Circuit maturation can promote age-appropriate levels of exploration, allowing the mPFC to encode a differentiated repertoire of threat responses. However, the causal relationships between the evolution of mPFC circuits and the maturation of the learned response to threats are still poorly understood.

Methods:We have developed a modified version of platform-mediated avoidance (PMA) that is compatible with the study of developing mice. In this test, a conditioned tone prompts rodents to navigate to a secure platform. Out-of-reach sweetly puffed scent canisters entice animals to explore between sound displays. We combined PMA with projection-specific optogenetic manipulations to test the hypothesis that maturation of PL-BLA and PL-NAc circuitry determines age-specific avoidance behavior.

Results:We found that learned threat avoidance behaviors are developmentally regulated. Whereas adults' threat memories are strong and enduring, adolescents show weak threat memories, and adolescents show transient suppression of threat memories (time on platform during recovery, main effect of age: P = 0.02, main effect number of trials: P = 0.23, interaction: P = 0.16 Tukey's corrected post hoc test: P35 vs. P60: P = 0.017). When we combined PMA with projection-specific optogenetic manipulations to test the hypothesis that the maturation of PL-BLA and PL-NAc circuitry determines age-specific avoidance behavior, we found that the behavioral contributions of PL to PMA are age-specific. Activation of PL-BLA reduced avoidance in adolescents by increasing the latency to enter the security platform. At P35, the same tampering had no net effect on platform time, but promoted safe platform entry while reducing platform dwell time. Finally, PL-BLA activation slightly improved adult PMA (time on platform during recovery, age main effect: P = 0.002, opsin main effect: P = 0.82, interaction: P = 0.002; post-test hoc with correction for Turkey: P23: P = 0.01, P35: P = 0.99, P60: P = 0.04). In contrast, PL-NAc activation had no effect on P23 or P35, but reduced avoidance in adults by increasing latency to step onto safety platform (time on platform during recovery, main effect of age: P = 0.07 , study # Main effect: S = 0.13, Interaction: P = 0.08, Post hoc test with Tukey's correction: P60: P = 0.01). PL-BLA knockdown at P23 had no effect on PMA (P = 0.2, Student's t-test), whereas PL-NAc knockdown at P35 prevented avoidance (P = 0.02, Student's t-test) . greater platform security and longer stay time on the platform.

Conclusions:Taken together, these results support a model in which distinct rearrangements of frontolimbic circuits, rather than simply amplifying development, drive age-specific threat behaviors. In the juvenile stages, LP circuits may not play a key role in avoidance; instead, BLA and NAc can handle learned threat prevention. During adolescence, changes in PL dynamics may favor PL-NAc activation, promoting exploration even during threat encounters. In ongoing work, we use fiber photometry to monitor neural dynamics during development. By performing specific activity manipulation and monitoring of the developing circuit, our studies will be among the first to establish causal relationships between mPFC circuit dynamics and the maturation of threat-induced behaviors. By uncovering the pathway through which threat avoidance arises, our research will provide important foundations for understanding how genetic and environmental insults alter developmental trajectories and shift the balance towards developmental impairments.

Key words:mPFC, evolutionary history, active avoidance, threat conditioning, frontolimbic network

To disclose:Nothing to disclose.

Ashley Marquardt*, Jonathan Van Ryzin, Mahashweta Basu, Seth Ament, Margaret McCarthy

University of Maryland School of Medicine, Baltimore, Maryland, USA

Background:Social play is a dynamic and well-maintained behavior known to be sexually differentiated. In most species, males play more than females, a difference between the sexes determined by the medial amygdala (MeA). To investigate whether the transcriptional signatures underlying gambling also differ by sex, we performed RNA sequencing of MeA samples from strong and weak players of both sexes in young rats. Using weighted gene coexpression network analysis (WGCNA), we identified 22 coexpression modules, or networks of genes that are highly correlated in expression across samples. Of the 12 modules (for p < 0.05) that are significantly associated with gaming, almost all (11/12; ~92%) are gender-specific in expression, which correlates with game expression in only one genre. These data suggest that there is a distinct transcriptome profile associated with play in male versus female MeA, a notable finding as MeA regulates many gender-typical adult social behaviors. We propose that this is not a coincidence: the gene networks associated with play in MeA are gender-specific because play modulates the circuits that drive different adult behaviors based on gender. To investigate this, we deprived male and female rats of play during the peak play window of adolescence and assessed the effects on various behaviors later in life, predicting that this would lead to behavioral disturbances later in life that would differ according to age. .

Methods:For 2 weeks during the peak play period (days 26 to 42 after birth), juvenile rats either experienced controlled housing conditions or were deprived of play by two different methods: complete social isolation or were placed in modified cages with plexiglass dividers perforated. to prevent gambling while allowing other social interactions ("game barriers"). All subjects (n=11-13/group) were then returned to normal housing and then assessed on a battery of adult behavior tests. When appropriate, one-way or two-way ANOVAs were performed, followed by Tukey's post hoc tests.

Results:In support of our hypothesis, we found that youth gambling prevention affected object memory (p=0.004), sexual behavior (p=0.01) and social preference (p<0.001) in adulthood only in males. There were no effects of play deprivation on anxiety-like behavior, gender preference, or social acceptance in either sex, nor on any rated behavior, including maternal behavior, in adult females.

Conclusions:According to the proposed hypothesis, game deprivation did indeed result in gender-specific effects on behavior later in life: men who were prevented from playing as teenagers had impairments in object memory and two evidences of sociosexual behavior in adulthood . Surprisingly, there were no effects on women for any of the behaviors studied, suggesting female resilience to adolescent isolation. We are currently repeating these experiments with a longer window of gaming deprivation (postnatal days 21 to 45) to see if this might reveal additional deficits in women. These findings, along with our previous RNA sequencing results, provide new insights into how games work and how and why this might differ by genre.

Key words:Social gaming behavior, RNA sequencing, sex differences, medial amygdala, behavior

To disclose:Nothing to disclose.

Yasmine-Marie Cissé*, Kristen Montgomery, Tracy Bale

University of Maryland School of Medicine, Baltimore, Maryland, USA

Background:Cumulative stress, including adverse childhood experiences (ACEs), repeated trauma, or stress due to racial discrimination, experienced before pregnancy is a predictor of adverse perinatal and neurodevelopmental outcomes. Although adversity is not unique to women, pregnancy is both a general and woman-specific physiological challenge. However, little is known about the biological mechanisms involved in the transmission of this persistent stress history signal. We have developed a new mouse model of maternal preconception stress (MPS) in which pups, but not males, are hypersensitive to stress in adulthood. Our previous work has shown a dramatic shift in protein content in circulating extracellular vesicles (EVs) relative to proteins involved in metabolism in mothers with MPS, particularly during pregnancy. This change is associated with glucose intolerance in mothers with MPS in mid-pregnancy. We hypothesize that the increased metabolic demands of pregnancy unmask the programming of negative preconception experiences that alter signaling at the maternal-fetal interface, resulting in sex-specific changes in the neurodevelopment of the offspring.

Methods:Adult female mice were exposed to chronic stress at 4-10 weeks of age. Mice were fed two weeks after stress recovery to minimize the confounding effects of acute pre-mating stress. To assess the lasting effects of MPS on the maternal and fetal compartments, placentas, adjacent uterine tissues and fetal brains were collected at mid-gestation, E12.5, coinciding with complete placental differentiation and development of the hypothalamus. Using Sim1-Cre x Ribotag mice, RNA transcripts specific for hypothalamic neurons and enriched in the paraventricular nucleus (PVN) were isolated and sequenced to assess the effect of MPS on offspring hypothalamic development and adult function (PN2, PN21, and PN70). Body weight and food intake were monitored in a separate cohort of pups challenged with a high-fat, low-fiber (HFD) diet from 4 to 10 weeks of age.

Results:In mid-gestation, reproductive tissues at the maternal-fetal interface in mothers with MPS showed extensive changes in cell and lipid metabolism in an offspring, specifically by sex. Female offspring showed increased levels of differential hypothalamic gene expression in response to MPS and altered expression of metabolic genes in PVN-enriched hypothalamic neurons throughout development, reflecting metabolic changes at the maternal-fetal interface with persistent sex-specific effects in offspring in the development of the hypothalamus. Unlike the control pups, the MPS pups were likely to gain weight when challenged with a high-fat, low-fiber diet.

Conclusions:These data highlight the persistent effects of cumulative stress exposed to biases that occur during pregnancy to alter metabolic signaling at the maternal-fetal interface, ultimately affecting offspring's sex-specific hypothalamic development and susceptibility to metabolic dysfunction. indicate risk for other neurodevelopmental disorders.

Key words:Stress models, hypothalamic development, RiboTag, RNA sequencing

To disclose:Nothing to disclose.

Daniel Roche*, Clayton H. Brown, David Gorelick, Chamindi Seneviratne, Bankole Johnson, Melanie Bennett

Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA.

Background:Post-traumatic stress disorder (PTSD) and alcohol use disorder (AUD) often coexist. This comorbidity is associated with worse symptom severity and treatment outcomes for each condition. Black/African-American (B/AA) people are more likely than other races to be exposed to traumatic events, experience more severe PTSD symptoms, and experience worse consequences of alcohol use. As they have been excluded from treatment studies in the past, treatments for PTSD and AUD that are effective for B/AA people are urgently needed. The anticonvulsant drug pregabalin, through its affinity for the alpha-2-delta helper site of voltage-gated calcium channels, may help restore balance to dysregulated glutamate and GABA systems that appear to underlie PTSD such as AUD. Pregabalin has shown preliminary efficacy in the treatment of AUD, generalized anxiety disorder and PTSD. The aim of this randomized controlled trial was to evaluate whether pregabalin reduces alcohol consumption and improves PTSD symptoms in B/AA subjects with concomitant PTSD and AUD compared to placebo. Furthermore, a personalized medicine approach was used to investigate whether a variation of SLC6A1, i.e. the gene encoding the GABA transporter GAT-1, affects the response to pregabalin. There is evidence that GAT-1 is down-regulated in AUD and up-regulated by pregabalin administration. In B/AA, variants in the insertion of the promoter region of the SLC6A1 gene (i.e. non-insertion/insertion or insertion/insertion (NI/I or I/I) compared to non-insertion/non-insertion (NI/NI) exhibit levels significantly higher levels of GAT-1 promoter activity.

Methods:This study (NCT02884908) was a prospective genotyped, double-blind, placebo-controlled, 12-week clinical trial to evaluate the efficacy of pregabalin versus placebo in reducing alcohol consumption and PTSD symptoms. Participants were randomized to receive pregabalin 450 mg/day or placebo on a 1:1 schedule for 12 weeks, with each medication group also stratified by SLC6A1 genotype (NI/I/II vs. NI/NI). Due to the low allele frequency, individuals with the double copy insertion were combined into one group with those with the single copy (ie, NI/I/II). At each of the 12 weekly visits, participants received standardized guided interviews to improve medication adherence and completed measures to assess alcohol use and PTSD symptoms. The primary endpoints were the number of days of heavy drinking (HDD) assessed using the Time Line Follow-up Interview (TLFB) and the severity of PTSD symptoms in Groups B and E assessed using the checklist. PTSD symptom check for DSM-5 (PCL-5 ). Secondary outcomes were the number of days of alcohol abstinence and consumption per drinking day, as assessed by the TLFB, and the overall severity of PTSD symptoms, as assessed by the DSM-5 and PCL-5 Physician Administered PTSD Scale (CAPS -5). The study was actively recruiting from 07/2017 to 11/2021, with enrollment suspended for approximately one year (03/2020 - 02/2021) due to the COVID-19 pandemic. Power analyzes showed the need to recruit n = 307 and randomize n = 203 to detect a medium-sized drug effect. In fact, this study included n = 149 and randomized n = 54 B/AA participants. A modified intention-to-treat analysis was performed that included n=44 B/AA subjects who received at least one dose of medication (n=26 pregabalin; n=18 placebo). Mixed effects repeated measures models adjusted for a pre-onset assessment of PTSD or alcohol use were used to compare the change in the twelve weekly assessments between the two medication conditions. To test whether drug response differs by genotype, the models were rebuilt, adding the SLC6A1 genotype as the main effect and the interaction term.

Results:Participants reported significant reductions in alcohol consumption (HDD, days abstinent, and drinks per day consumed) and PTSD symptoms (groups B and E and overall PTSD symptom severity) during the 12-week study. However, there was no difference between medication status or a pharmacogenetic effect on any of the primary or secondary endpoints.

Conclusions:Pregabalin did not reduce alcohol consumption or improve PTSD symptoms in B/AA subjects with comorbid AUD and PTSD, and genetic variation in GAT-1 activity was not associated with treatment outcomes or drug efficacy. However, this study was severely understaffed and these results, particularly the pharmacogenetic findings, should be viewed with caution due to the small sample size. More studies are needed to identify new and specific drug treatments for B/AA with AUD and/or PTSD.

Key words:Treatment of alcohol use disorder, post-traumatic stress disorder, randomized controlled trial, pharmacogenetics, African American

To disclose:Nothing to disclose.

Sheila Rauch*, Oluwatoyin Thompson, Anna Woodbury, Kathryn Black, Tahira Scott, Syreese Fuller, Jessica Maples-Keller, Barbara Rothbaum, Melba Hernandez-Tejada, Hyochol Ahn

Atlanta VAHCS, Emory University, Atlanta, Georgia, USA. UU.

Background:Chronic pain, or "pain that lasts longer than 3 months or recurs,"5 costs the United States hundreds of millions of dollars each year.2 Severe pain is approximately 1.5 times more common in veterans than in veterans. non-veterans.3 Among veterans, chronic pain is common Pain is a strong risk factor predicting suicide at all shifts.6 Commonly prescribed medications to treat chronic pain, such as opioids and NSAIDs, carry a higher risk for patients. free self-administered treatment, transcranial direct current stimulation (tDCS), in the management of chronic pain in veterans undergoing an intensive outpatient treatment program for mental health problems. tDCS is a painless, non-invasive brain stimulation treatment that uses direct electrical currents to stimulate specific parts of the brain and modulate neural activity. tDCS produces analgesic effects and improves pain system functioning through direct effects on motor, somatosensory, and frontal cortices involved in pain sensitivity. 1.4 tDCS has not yet been evaluated for chronic pain in veterans. We are evaluating the acceptability and effectiveness of tDCS for chronic pain in veterans who have completed the Emory Healthcare Veterans Intensive Outpatient Program (EHVP-IOP)7.

Methods:To date, 8 veterans with chronic pain in the EHVP-IOP have undergone staff-supervised tDCS sessions. Beginning on day 1, tDCS was administered at a constant current of 2 mA for 20 minutes per daily session for up to 10 sessions over 2 weeks using a Soterix 1x1 tDCS Mini-CT Stimulator (Soterix Medical Inc., NY). The team reviewed a medical assessment of pain. To measure chronic pain levels, participants completed the Defense and Veterans Pain Rating Scale (DVPRS) daily before and after each session and overall. On days 1 and 12, they completed Questionnaires 3a and 8a of the Patient Reported Outcomes Measurement Information System (PROMIS). To assess comorbid conditions such as PTSD and depression, participants completed the Post Traumatic Stress Disorder Checklist (PCL-5) and Patient Health Questionnaire (PHQ-9) on days 1, 3, 5, 8 , 10 and 12. Post-treatment follow-up was at 1, 3, 6, 9 and 12 months.

Results:We currently have 8 Veterans enrolled in the EHVP-IOP plus tDCS program and will have all available Veterans enrolled by mid-November (estimated 18 Veterans). Preliminary analyzes are promising and address feasibility and acceptability. In summary, veterans find the use of the tDCS device with remote monitoring acceptable and can successfully self-manage under televideo surveillance by study staff with few reported problems. An aggravation of the headache occurred in a veteran who decided to discontinue treatment. As expected, significant and large reductions in PTSD were reported with the EHVP-IOP program (t(5) = -2.79, p = 0.03, d = -1.3). The pain reduction measured with DVPRS shows a small to median effect size (t (5) = 1.00, p = 0.18, d = 0.41), which may not be statistically significant due to the small size of sample. Updated results are presented on the poster, including patient-level pain data to illustrate veterans' response during the two-week EHVP-IOP.

Conclusions:Based on this open-label study, tDCS is a viable and acceptable pain intervention for concomitant use in mental health intensive care outpatient settings. The effect on pain is promising, with little or moderate pain relief as part of the daily tDCS regimen. Additional controlled studies with a large sample are needed to demonstrate efficacy. The pain reported in the sample has a heterogeneous approach (fibromyalgia, knee, migraine, etc.). Further analysis within subgroups is required.

Key words:Pain meds, veterans, treatment, PTSD, depression

To disclose:Nothing to disclose.

Roberto Morales-Silva, Ursula Gelpi-Domínguez, Joshua Perez-Torres, Yobet Perez-Perez, Genesis Rodriguez-Torres, Marian Sepulveda-Orengo*

Ponce University of Health Sciences, Ponce Research Institute, Ponce, Porto Rico

Background:A correlation between post-traumatic stress disorder (PTSD) and substance use disorder (SUD) has been identified, and stress has been associated with a greater likelihood of relapse into addiction. In addition, stress is associated with a greater likelihood of relapse. Studies using different models of PTSD and a short-access cocaine self-administration paradigm in male rodents have yielded variable results depending on specific experimental conditions. For example, a preclinical study showed that rats exposed to a modified prolonged stress of a single injection prior to self-administration of short-access (2 hours) cocaine showed decreased cocaine self-administration, whereas rats exposed to a single sustained injection of stress before cocaine self-administration Stress exposed to a stimulus-induced decrease in priming showed resetting, with no effect on acquisition or cessation of cocaine self-administration. On the other hand, it has been shown that stress in early life facilitates the acquisition of cocaine, but does not alter the recovery of cocaine seeking behavior. However, the effects of chronic stress and prolonged access cocaine self-administration on cocaine seeking in male or female rats have not been reported. We hypothesize that chronic stress prior to cocaine self-administration increases cocaine use in male and female rats. Furthermore, we predict that forced abstinence will result in an active lever-press increase in stimulus reactivity after 30 days of abstinence compared to 15 days in both sexes, with male rats exposed to stress and cocaine compared to a higher level. high. Female rats show incubation of cocaine craving.

Methods:We applied an unavoidable paradigm of electroshock with an intensity of 0.50 mA (randomly presented) for 5 days, followed by 6-hour sessions of prolonged access cocaine self-administration for 10 days and then forced periods of 15 or 30 days. female rats. We then examined memory retrieval stimulated by cues and cocaine.

Results:Our data show that chronic stress prior to cocaine acquisition reduces cocaine use in female rats compared to males. Furthermore, after 15 days after weaning, signal reactivity appears to decrease in both male and female rats without affecting cocaine-induced memory retrieval. Interestingly, after 30 days of abstinence, female rats show greater reactivity to stimuli in the stressed group compared to non-stressed rats, while male rats show similar reactivity to stimuli in both groups. Furthermore, after 30 days of abstinence, the stressed male rats showed an increase in cocaine-induced memory recall compared to the non-stressed group, while the female rats showed no difference.

Conclusions:Our results suggest that the stress effects of prior chronic cocaine exposure on the incubation of cocaine-seeking behavior depend on the duration of the abstinence period, suggesting that there are distinct neurophysiological phases during forced abstinence. In addition, chronic stress prior to extended access cocaine self-administration leads to gender differences in cocaine consumption and use, cue reactivity, and cocaine-induced memory recall. Our results provide evidence that the stress of prior cocaine exposure induces sex-related differences in cocaine seeking behavior.

Key words:Gender differences in cocaine use, chronic stress, development of cocaine craving

To disclose:Nothing to disclose.

Hannah Elam*, Alexandra McCoy, Angela Boley, Daniel Lodge

UT San Antonio Health Sciences Center, San Antonio, Texas, USA

Background:Post-traumatic stress disorder (PTSD) is a psychiatric disorder that affects approximately 8% of the US population. In addition to the core symptoms of the disorder, patients with PTSD often have a comorbid diagnosis, including psychosis. The symptoms of psychosis are thought to be caused by increased mesolimbic dopamine transmission, but no clear histopathology has been identified in these cells. Instead, hyperactivity in the upstream brain regions that regulate the activity of dopaminergic neurons in the ventral tegmental area (VTA) contributes to psychosis-like behavior. Two such regions are the paraventricular nucleus of the thalamus (PVT) and the ventral hippocampus (vHipp), which synergistically regulate the activity of VTA dopaminergic neurons through a multisynaptic circuit starting with convergent inputs to the nucleus accumbens (NAc). We have previously shown that activation of the PVT-NAc or vHipp-NAc projections significantly increases the activity of the VTA dopaminergic neuron population, defined as the number of neurons that fire spontaneously. These data suggest that post-stress hyperactivity in PVT or vHipp may contribute to psychosis-like behavior in a rodent model used to study PTSD. Interestingly, hippocampal and thalamic regulation of VTA population activity requires simultaneous activity from both regions, suggesting that targeting either region may be a novel site of intervention for comorbid PTSD-associated psychosis.

Methods:In this study, we induced stress-related pathophysiology in male Sprague-Dawley rats using the two-day unavoidable electroshock procedure. To selectively inhibit PVT-NAc or vHipp-NAc projections, we use a chemogenetic approach. A Cre-dependent inhibitory DREADD was expressed in PVT or vHipp. At the same time, a retrograde Cre virus was injected into the NAc. This allowed selective inactivation of these protrusions after administration of Compound 21 (3 mg/kg; i.p.). To study changes in the function of the dopamine system, we use in vivo electrophysiology.

Results:A two-day inescapable paw shock resulted in increased activity of the dopaminergic neuron population, consistent with what has been observed in other rodent models used to study psychosis. Chemogenetic inhibition of PVT-NAc projections or vHipp-NAc projections after stress restored function of the dopamine system.

Conclusions:These results demonstrate that the aberrant neuronal dopamine activity observed after stress can be reversed by inhibiting the activity of the PVT-NAc or vHipp-NAc projections. Here, we provide evidence that PVT or vHipp may be new therapeutic targets to reduce psychotic symptoms seen in PTSD.

Key words:Psychosis, Chemogenetics, Electrophysiology

To disclose:Nothing to disclose.

Maryam Sorkhou*, Elle Wadsworth, Samantha Goodman, David Hammond, Tony George

University of Toronto, Toronto, Canada

Background:Since the legalization of recreational cannabis use in Canada in 2018, an emerging public health concern is whether cannabis use will increase among people with mental health disorders. Compared to the general population, problematic cannabis use increases in individuals with mental health disorders, including those with psychotic spectrum, mood and anxiety disorders. Furthermore, problematic cannabis use is associated with more severe psychopathology and worse functional outcomes. Therefore, one must assess whether legalization has caused changes in patterns of marijuana use among psychiatric populations. We examined whether there are significant changes in pre- and post-legalization patterns of cannabis use in a nationally representative sample of Canadian adults who suffered from mental illness in the past 12 months following the survey.

Methods:Data were from Canadian respondents (N = 13,527) between cycles 1 (pre-legal; Aug-Oct 2018), 2 (post-legal; Sep-Oct 2019) and 3 (post-legal; Sep-Oct 2019). 2019). October 2020) of the International Cannabis Policy Study (ICPS). Binary logistic regressions and repeated measures ANOVAs examined changes in daily and 30-day cannabis use before and after legalization among those who reported 12 months of experience with anxiety, depression, PTSD, schizophrenia/psychosis, or bipolar disorder.

Results:Respondents who reported symptoms of schizophrenia used cannabis significantly more frequently after legalization (OR = 5.9, CI = 1.9-15.9; p < 0.01;). Daily cannabis use did not increase in other diagnostic groups or in non-psychiatric populations after legalization. Similarly, cannabis use increased in the last 30 days after legalization only among respondents who reported symptoms of schizophrenia (p < .05).

Conclusions:Our preliminary results suggest that patients with schizophrenia experienced selective increases in daily and 30-day cannabis use within the first two years of cannabis legalization in Canada.

Key words:Cannabis Use, Schizophrenia (SCZ), Depression and Anxiety, PTSD, Cannabis Use Disorder

To disclose:Nothing to disclose.

Ginger Nicol*, Adam Locke, Tooraj Mirshahi, Daniel Mueller, Eric Lenze, John Newcomer, J. Philip Miller, Anne Justice

University of Washington, St. Louis, Missouri, USA. UU.

Background:Obesity and its metabolic consequences significantly contribute to accelerated aging and shorten the life expectancy of people with psychiatric disorders. The risk of antipsychotic drug-induced weight gain (AIWG) is believed to be strongly genetic, but our understanding of these contributors remains limited. Characterization of the genetic variation that affects the AIWG is essential for the development of precision treatments and decision support tools in psychiatry.

The present analysis represents the first step in the NIH-funded multi-omic Obesity Related to Antipsychotic Liability and Exposure (ORAcLE) study, a multi-study consortium designed to collect genetic and clinical data from large health care systems. Cohort studies and combination of randomized controlled trials. both to validate previously reported genetic contributions to AIWG risk and to identify new common variants that affect AIWG risk.

The Geisinger MyCode Community Health Initiative, a population health genomics project with genetic and clinical data from approximately 185,000 individuals, was used to test the initial analytical approach for the entire ORACLE consortium. Using the preliminary genomic wide association study (GWAS) from the Genetic Investigation of Anthropometric Traits (GIANT) consortium, which includes more than 1.1 million European participants, we calculated polygenic risk scores (PRS) for body mass index (BMI), then tested these PRS to determine their effect on AIWG as measured by longitudinal change in BMI during treatment with an atypical antipsychotic.

Methods:Persons in the MyCode dataset with >2 BMI measurements >30 days apart while being prescribed an atypical antipsychotic medication were eligible for inclusion in the analyses. Baseline and non-physiologically plausible change values ​​for weight, height or BMI were removed. Changes in height, weight, or BMI between visits due to unit conversion errors or injuries such as a heart attack. B. Amputations have also been removed. Weights collected during pregnancy and 6 months after delivery and weights collected after bariatric surgery were excluded from the analyses.

We used a mixed linear model regressing BMI with intercept and time (years) as random and fixed effects to derive the AIWG slope stratified by sex and ancestry. We performed analyzes of the general change in BMI in the population of all eligible individuals and only for "winners" (ie, only individuals with a positive AIWG slope). PRS weights were estimated in SbayesR.

Association analyzes between standardized PRS and AIWG were performed using generalized linear models, while households were accounted for using the general estimating equation (GEE). All models had age, age2, sex, baseline BMI, duration of follow-up, and five genetically reported major components of ancestry [European (EUR), African descent (AA), Native American/Amerindian (AMR), East Asian (EAS) , South Asia (SAS)]. Incremental R2 values ​​were estimated in an unrelated subset of participants using linear regression. The association between PRS and baseline BMI was also evaluated.

Results:There were 8493 participants (97% Caucasian, 68% female, 61% gained weight while taking antipsychotic medication) with actionable data who met the inclusion criteria for the analysis. There was an average of 33 observations (SD=58) per individual participant, with a mean of 3.7 (SD=3.7) years of follow-up and mean AIWG of 0.18 kg/m2 per year (0.93).

The final PRS included 1,080,060 variants and was significantly associated with baseline BMI (P = 1 × 10-305, β = 4.03, R2 = 14.4%). We observed significant relationships between cross-sectional BMI PRS and AIWG in all subjects (R2 = 0.3%, P = 4 × 10-8, β = 0.069 BMI units/year) and in "winners" (R2 = 0 . 3%, P = 6.5×10-6, β = 0.051 kg/m2/year).

Finally, there was also a small but significant difference (0.125 kg/m2/year, P=2×10-4) in the adjusted mean AIWG between the lowest and highest quintile of the PRS.

Conclusions:These results demonstrate that genetic variants associated with cross-sectional measures of obesity, represented by a PRS derived from the ongoing GIANT IMC GWAS consortium, are associated with AIWG. This result extends observations from smaller studies that AIWG has a clear hereditary component detectable with a PRS originally designed to detect genetic risk for obesity.

The proportion of variance explained by cross-sectional BMI-PRS in the AIWG was significant but small, suggesting that overall obesity risk and associated signaling pathways may not be the primary mechanism for the AIWG. This further motivates the consortium's primary goal of pooling relevant genomic and clinical data to discover new genetic variants associated with AIWG. Our ongoing analyzes in larger population samples representing greater diversity will identify specific longitudinal AIWG modifiers and affected molecular signaling pathways.

Key words:Weight gain with antipsychotic drugs, population genetics, molecular genetics, human genetics

Disclosures: Alkermes, Novartis: consultants (own), LB Pharmaceuticals: subsidy (own)

Federica Veneziani*, Aleksandra Marakhovskaia, Clementine Quintana, Lakshmi Rajakrishna, Jean-Martin Beaulieu

University of Toronto School of Medicine, Toronto, Canada

Background:Olanzapine is a second-generation antipsychotic used to treat schizophrenia and mood disorders. The mechanism of action of this drug involves the modulation of multiple G protein-coupled receptors (GPCRs). Chronic olanzapine administration is associated with an increased risk of metabolic syndrome, a clinical condition characterized by the coexistence of obesity, dyslipidemia, diabetes and hypertension. The mechanisms by which second-generation antipsychotics induce the metabolic syndrome remain unclear. However, central or peripheral signaling functions have been proposed. The hypothalamus is an important regulator of energy metabolism, so this brain structure may be involved in the metabolic syndrome induced by antipsychotic drugs. Here, we examine the potential contribution of hypothalamic GPCRs to the onset of metabolic dysfunction induced by antipsychotic drugs.

Methods:Animals: All animal procedures were performed in accordance with Animal Care Council of Canada guidelines and were approved by the University of Toronto Animal Ethics Committee. The experiments were performed on female wild-type C57BL/6J mice at approximately 7 weeks of age. For olanzapine treatment, pure olanzapine was mixed with a high fat diet. The vehicle group received only the high-fat diet. Mice were treated for 28 days.

Stereotactic injection: mice were divided into three lots: H1R knockout, CB1R knockout and control group (n=24/each). Knockout (KO) was induced with a bidirectional viral CRISPR approach using AAV-MeCP2Cas9. Viruses were administered by stereotaxic hypothalamic injection.

Characterization of the phenotype: To characterize the phenotype, the following parameters were measured: food intake, weight gain, blood glucose, serum insulin, HDL, LDL and triglycerides. Fatty liver disease was assessed using Oil Red O stain and Masson's trichrome stain.

statistical analysis

Data are presented as mean ± SEM. A one-way ANOVA followed by a Bonferroni correction was used for cross-group comparison. Differential gene expression (DEG) analysis, signaling pathway analysis, and gene coexpression network analysis were performed using the Mattest-Matlab package, Ingenuity signaling pathway analysis (Qiagen IPA), and the WGCNA R- Studio, respectively.

Results:Analysis of hypothalamic gene expression in adult female mice allowed the identification of a transcriptomic signature of olanzapine-induced metabolic syndrome. So, using an unbiased approach, we identified two GPCRs: histamine receptor 1 (H1R) and cannabinoid receptor 1 (CB1R) that appear to play critical roles. Therefore, we implemented CRISPR/Cas9 mediated approaches to knock down each receptor on hypothalamic neurons.

Hypothalamic H1R neuronal KO is responsible for weight gain but not glucose impairment or changes in lipid metabolism.

Mice with H1R-KO in hypothalamic neurons showed statistically significant weight gain compared to controls (p < 0.001). The present weight gain appears fully comparable to the effect of olanzapine treatment in control mice. Furthermore, olanzapine treatment in H1R-KO mice does not result in increased weight gain. Analysis of other metabolic parameters (glucose, insulin, triglycerides, LDL, HDL) shows that H1R-KO in hypothalamic neurons does not seem to lead to glucose deficiency or lipid dysfunction per se, with no statistical difference between H1R mice. -KO- and to control. rats. Analysis of the DEG pathway between H1R-KO and control mice shows that the neuropeptide Y (NPY) pathway is upregulated in H1R-KO mice. On the other hand, comparison of gene expression of olanzapine-treated H1R-KO mice with vehicle-treated H1R-KO mice highlights that olanzapine not only upregulates the NPY pathway but also induces complete downregulation. in the pro-opiomelanocortin (POMC) signaling pathway.

CB1R KO in hypothalamic neurons is able to restore the full phenotype of olanzapine-induced metabolic syndrome.

CB1R KO mice show no difference in weight gain compared to controls. However, administration of olanzapine to both groups shows that CB1R KO mice have lower weight gain compared to controls (p<0.01). Furthermore, CB1R KO mice treated with olanzapine reduced glycemic dysfunction (p<0.001), decreased triglyceride (p<0.001) and LDL (p<0.001) levels, and increased HDL levels (p<0.0001) in comparison with mice. to treated controls. The analysis of the DEG pathway between CB1R-KO and control mice, both treated with olanzapine, shows that, in this case, the NPY pathway is reduced in CB1R-KO mice. Furthermore, a comparison of the hypothalamic coexpression network of CB1 KO mice with control, both treated with olanzapine, suggests that CB1 receptor inactivation results in a dissociation of H1R expression and key regulators of metabolic homeostasis (NPY). , AGRP, POMC , NPY2R) induced).

Conclusions:These results suggest that the metabolic syndrome is a complex clinical phenotype in which central and peripheral dysregulations can interact, resulting in loss of metabolic homeostasis. On the other hand, the possibility of reversing the Metabolic Syndrome by targeting the hypothalamic CB1R opens up a promising perspective for therapeutic development.

Key words:Metabolic side effects, Antipsychotic-induced metabolic disorders, Metabolic syndrome, Antipsychotic-induced weight gain, Cannabinoid receptor

To disclose:Nothing to disclose.

Lindsay Strehle, Corena Grant, Lauren Otto, Leah Pyter*

Ohio State University, Columbus, Ohio, USA. UU.

Background:Breast cancer is the most common type of cancer in women worldwide. After diagnosis but before cancer treatment, up to 30% of these patients report mood disorders (eg, anxiety, depression) that limit quality of life and affect adherence to therapy. Remarkably, our mouse mammary tumor model recapitulates negative affective behaviors observed in cancer populations that are consistent with elevated pro-inflammatory mediators in the midbrain and hippocampus. Indeed, neuroinflammation is a proposed mechanism underlying the etiology of mood disorders and may therefore contribute to cancer-associated mood disorders by modulating neurotransmission (eg, serotonin metabolism). However, the cellular mechanisms by which tumor-induced neurobehavioral changes occur remain unknown. We hypothesize that microglia are the primary cells that drive tumor-induced neuroinflammation that contributes to affective behavior and altered serotonin metabolism.

Methods:Young adult female Balb/c mice were induced with a syngeneic, non-metastatic, 67NR orthotopic mammary tumor; Tumor-free controls underwent sham surgery. Experiment 1 examined brain region-specific microglial morphology (Iba1 immunohistochemistry) and serotonin-related gene expression (Tph2, Th, Slc6a4) and Percoll-enriched brain microglial cell gene expression (Il1b, Il6, Tnfa, Tlr4 ). Experiment 2 tested microglia requirement on tumor-induced neuroinflammatory/serotonin/behavioral outcomes by depleting microglia using a colony stimulating factor 1 receptor inhibitor (PLX-5622) in feed.

Results:In Experiment 1, breast tumors increased gene expression of the midbrain serotonin transporter (Slc6a4) and a rate-limiting serotonin enzyme (Tph2) compared to tumor-free controls (t-test: p<0.05). In particular, in brain microglial cells, tumors upregulated the Toll-like receptor 4 gene compared to controls (t-test: p<0.05); Microglial immunohistochemical analyzes are ongoing. In the open field trial of Experiment 2, mice with tumors unexpectedly increased locomotion at the risk center of the field compared to mice without tumors; these tumor-induced risk behaviors were attenuated by PLX-5622 chow (2-way interaction ANOVA: p<0.05). Likewise, mice with tumors were less averse to approaching a new object, a risk-taking behavior that was reversed when microglia were depleted (interaction 2-way ANOVA: p < 0.05).

Conclusions:These results suggest that microglia may have a regional involvement and mediator in tumor-induced neuroinflammation and neurotransmission. This research will advance our understanding of the mechanisms underlying behavioral disorders associated with cancer to identify specific cellular and/or molecular targets to prevent or mitigate them.

Key words:Microglia, risk behavior, neuroinflammation, serotonin, cancer

To disclose:Nothing to disclose.

Nina Dedic*, Eva Hajos-Korcsok, Phil G. Jones, Colleen Synan, Serena Wu, Christoph Anacker, Steven P. Vickers, Jacob Hecksher-Sørensen, Snezana Milanovic, Linda J. Bristow, Kenneth S. Koblan

Sunovion Pharmaceuticals, Inc., Marlborough, Massachusetts, EE. UU.

Background:Ulotrone (SEP-363856) is an amine-associated receptor 1 (TAAR1) and 5-HT1A agonist currently in phase 3 clinical trials for the treatment of schizophrenia. Metabolic syndrome (eg, central obesity, dyslipidemia, hypertension, hyperglycemia, etc.), which can be induced or exacerbated by current class of antipsychotic drugs (APDs), is common in schizophrenic patients. Therefore, the need for new treatments that do not have APD class-specific metabolic side effects is evident. Ulotrone has no significant activity at receptors commonly associated with APD-induced metabolic changes (ie, D2, 5-HT2C, H1, and M3). Recent preclinical findings have identified TAAR1 as a novel regulator of metabolic control and a promising target for obesity and type 2 diabetes. Here we evaluate the risk-benefit profile of ulotronate for the treatment of schizophrenia, assessing its effects on metabolic parameters in rodents from diabetes, obesity, and iatrogenic weight gain.

Methods:The effects of 15- and 35-day oral treatment with ulotrone (0.3-10 mg/kg) on ​​body weight, food intake, and metabolic parameters were studied in Sprague-Dawley rats fed a high-fat diet (HFD). a mouse model of diet-induced obesity (DIO). Furthermore, the effects on body weight in a rat (8-day treatment) and mouse model (21-day treatment) of olanzapine and corticosterone-induced body weight gain (1-10 mg/kg, po), respectively . , were determined. Glucose tolerance was improved in diabetic C57BL/6J and db/db mice after acute oral administration (0.3-10 mg/kg) and in DIO mice after 15 days of administration (0.3-10 mg/kg, po ). The acetaminophen absorption test and the phenol red test were used to assess effects on gastric emptying in C57BL/6J mice (0.3-10 mg/kg, po). To obtain information about the neurocircuitry modulated by ulothrone, whole brain 3D c-fos imaging was performed in C57BL/6J mice. Comparisons between groups were analyzed using one-way ANOVA followed by appropriate post hoc tests. Treatment effects over time were assessed using repeated measures ANOVA. Statistical comparisons of c-fos data were based on ROIs from the Allen Brain atlas or on evenly spaced voxels using negative binomial regression.

Results:Acute administration of ulotronate reduced plasma glucose excursion in a dose-dependent manner in C57BL/6J (F(4, 47) = 15.07, p<0.0001, n=10/group) and diabetic db/db( F(4, 45) = 51.41, p<0.0001, n=10/group) mice during an oral glucose tolerance test (OGTT). Delayed gastric emptying was observed in mice in response to ulotron treatment, which is likely the main mechanism for reduced glucose excursion during OGTT (F(5, 56) = 29.90, p<0.0001, n =10/group). Administration of ulotronate to rats under HFD resulted in a significant and dose-dependent reduction in body weight (F(4, 55) = 40.12, p < 0.0001, n = 12/group), food intake (F (4, 55) = 22.43, p < 0.0001, n = 12/group) and hepatic triglyceride content (F(4, 55) = 3.3, p < 0.02, n = 12/group ) compared to vehicle controls. Faster reversal of olanzapine-induced weight gain (F(5, 67) = 17.04, p < 0.0001, n = 12-13/group) and food consumption (F(5, 67) = 30, 69, p < 0.0001, n = 12-13/group) in rats switched to ulotron treatment compared to vehicle alone. Consistent with body weight reduction effects in rats, chronic treatment with ulotron normalized and reduced corticosterone-induced body weight gain in mice (F(4,45)=46.1, p<0.0001, n= 8-12/group). in the dose-dependent DIO model (F(4, 55) = 5.5, p = 0.0009, n = 12/group). In addition, chronic treatment with ulotron improved glycemic control in DIO mice, as evidenced by reductions in fasting plasma glucose (F(4, 55) = 6.3, p = 0.003, n = 12/group) and levels of insulin (F(4, 55) = 2.9, p = 0.03, n = 12/group) and increased glucose tolerance (F(4, 55) = 4.51, p = 0.003, n = 12 /group). Whole brain imaging revealed neural activation (increased c-fos expression) of appetite regulatory signaling pathways associated with meal completion (initiated by signaling in the hindbrain nucleus of the tractus solitarius and mediated by the lateral parabrachial nucleus). Neural activation has also been observed in subregions of the hypothalamus associated with the regulation of food intake and the integration of peripheral metabolic signals, including the arcuate and paraventricular nuclei. The c-fos signature of ulotronate differed from that of typical haloperidol APD.

Conclusions:Current data show that ulotrone not only lacks APD-induced metabolic liabilities, but can also reduce body weight and improve glycemic control in rodent models. Underlying mechanisms likely include TAAR1-mediated peripheral effects on glucose homeostasis and gastric emptying and/or direct modulation of homeostatic and hedonic neurocircuitry that regulate energy balance. The positive effects of ulotrone on metabolic parameters may indicate an improved risk-benefit profile compared to the established pharmacological class of APD. Furthermore, current preclinical results support the evaluation of TAAR1 agonists for the treatment of metabolic disorders.

Key words:TAAR1, New Treatment for Schizophrenia, Antipsychotic Drug-Induced Metabolic Dysfunction, Adverse Metabolic Events

To disclose:Sunovion Pharmaceuticals: Employee (Himself)

Natalie Zahr*, Edith Sullivan, Adolf Pfefferbaum

Stanford University, Stanford, California, USA

Background:The presence of the hepatitis C virus (HCV) affects the levels of metabolites detectable by magnetic resonance spectroscopy (MRS) in the brain. In particular, levels of striatal Cho (ie, choline-containing compounds) were found to be higher in HCV-seropositive individuals compared to seronegative individuals.

Methods:To determine whether liver fibrosis would affect brain metabolite levels irrespective of HCV status, MRS data collected in 3 regions of interest [ROI, corpus striatum (10.6 cc), cerebellum (9.8 cc) were evaluated. and bridge. (5.9 cc)] for their relationships to 2 serum-derived liver fibrosis markers. Cut-off scores for liver fibrosis were platelet aspartate aminotransferase ratio (APRI) > 0.7 and fibrosis score (FIB4) > 1.5 calculated in a cohort of 170 participants: 62 healthy controls (47.8 ± 19.9 years), 37 people with alcohol use disorder (AUD) (48.5 ± 10.6 years), 33 HIV-seropositive people (50.0 ± 9.1 years) and 38 people with comorbidity for AUD+ HIV (51.9 ± 8.6 years).

Results:Among all participants, 13 had APRI > 0.7 (1 control, 2 AUD, 4 HIV, 6 AUD + HIV) and 34 had FIB4 > 1.5 (4 controls, 5 AUD, 13 HIV and 12 AUD + HIV) . Gender did not differentiate the number of people with fibrosis (APRI p = 0.26; FIBR4 p = 0.30). Using non-parametric Wilcoxon ranking tests, an APRI was > 0.7 with highest striatal Cr (total creatine, Z = 3.3, p = 0.001), highest striatal Cho (Z = 4.2, p < 0 .0001) and higher striatal mI. (myo-inositol, Z = 2.7, p = 0.008); Metabolites in the other 2 ROIs were not distinguished by the APRI cutoff. FIB4 > 1.5 was associated with higher Cho striatal (Z = 3.1, p = 0.002) and superior striatal (Z = 2.6, p = 0.009) and pontine (Z = 2.8, p = 0.005) mi . For striatal Cho, multiple regression including HCV, APRI and FIB4 explained 16.6% of the variance and was determined by the APRI score (p = 0.0009, single contribution of 14.7% to the variance). A similar model (ie, including HCV, APRI, FIB4) resulted in the same pattern for striatal Cr (5.9% explained variance, driven by APRI p = 0.02); the model was not significant for striatal ml; The pontine ml was most affected by HCV (11.1% of the explained variance, HCV p = 0.01). An APRI > 0.7 was associated with lower verbal fluency scores (F-A-S, Z = -2.7, p = 0.006; Freda, Z = -2.6, p = 0.01). A FIB4 > 1.5 was also associated with lower verbal (Freda, Z = -3.1, p = 0.002) and figurative (RUFF, Z = -2.6, p = 0.009) fluency scores.

Conclusions:Taken together, these data suggest that the presence of liver fibrosis may selectively affect striatal metabolite levels. High concentrations of striatal Cho and mI indicate lipid accumulation that may contribute to the T1 signal hyperintensities seen in basal ganglia structures in liver cirrhosis. Correlations between higher fibrosis scores and impaired speech fluency suggest functional implications of these neurometabolic abnormalities measured in vivo.

Key words:Liver-brain axis, alcoholic liver disease, HIV, hepatitis C, basal ganglia

To disclose:Nothing to disclose.

Lauren Breithaupt*, Amanda Lyall, Felicia Petterway, Holly Carrington, Laura Holsen, Franziska Plessow, Yaen Chen, Jennifer Thomas, Madhusmita Misa, Elizabeth Lawson, Kamryn Eddy

Hospital General de Massachusetts, Boston, Massachusetts, EE. UU.

Background:Anorexia nervosa (AN) is a severe eating disorder characterized by maladaptive restrictive eating. Restrictive eating patterns often develop as goal-directed dieting behavior and transition to habitual restrictive eating, without motivation for valuable initial goals. The transition to habit-based behaviors may persist as a result of structural changes in the basal ganglia that occur as a result of extreme weight loss. It is unknown whether basal ganglia morphometry is altered in individuals with atypical anorexia nervosa (atypical AN) who are not underweight (BMI < 18.5 kg/m2) but who are clinically similar to AN. Based on previous literature, we hypothesized that participants with AN would have less volume and greater shape deformations in regions associated with the usual response, including bilateral putamen and caudate, compared to participants with atypical AN and healthy controls.

Methods:The sample included 77 women with AN (n = 30, x̄ age = 19.7, x̄ disease duration 5.0 years), atypical AN (n = 21, x̄ age = 18.3, x̄ disease duration 3.6 years) and healthy control women (n = 26, x̄ age = 18.0). T1-weighted images were processed using a standard internal pipeline that included: visual quality control, manual masking, and outlier detection. The Freesurfer v7.1 Recon-All function was used to segment the basal ganglia to extract regional volumes. Clinical characteristics between groups were evaluated using chi-square tests, analysis of covariance (ANCOVA) and post-hoc Tukey tests. Volume group comparisons were corrected for age and head size, corrected by Bonferroni, and p < 0.016 was considered statistically significant. The shape of the basal ganglia was processed using the ENIGMA shape channel to extract the logarithm of the Jacobian determinant. For group comparisons of basal ganglia shape, we performed paired vertex regression analyzes for each vertex in each region of interest, with age and estimated total intracranial volume (eTIV) as covariates. Benjamini-Hochberg correction was used for multiple comparisons with a false detection rate of 5% (q = 0.05).

Results:Contrary to our hypothesis, we found a significant group main effect on bilateral putamen volume and shape (left: F2.72 = 6.88, p = 0.0018; right: F2.72 = 7.23, p = 0, 0013). Subjects with atypical AN had lower volume and greater shape deformations in these regions compared to subjects with AN (R: p= .0013; L: p= .0014) and healthy controls (R: p= .0016; L: p=.002). We also found significant differences in the shape of the right caudate between atypical AN versus AN, but not between atypical AN and HC.

Conclusions:Our results suggest structural brain differences between individuals with AN and atypical AN who share similar clinical presentations. However, group differences in basal ganglia structures are even more pronounced in those with atypical AN compared with AN. Differences in gray matter in AN are often attributed to severe underweight status in individuals with AN. Our study suggests that structural differences in the basal ganglia persist with low weight, regardless of the clinical design. Our findings also complement clinical data showing that habitual restriction occurs in atypical AN. These results underscore the importance of restoring weight based on individual history to focus on the usual features seen in both AN and atypical AN.

Key words:Eating disorders, basal ganglia, habit

To disclose:Nothing to disclose.

Kelvin Lim*, Lisa Anderson, Erich Kummerfeld, Carol Peterson, Stephen Wonderlich, Ross Crosby, Scott Engel

University of Minnesota, Minneapolis, Minnesota, USA. UU.

Background:Negative affect has been implicated as a trigger and perpetuator of binge eating and purging behaviors in bulimia nervosa (BN). This relationship was supported by laboratory data and group analyzes of Instantaneous Ecological Assessment (EMA) data. However, treatment outcomes in BN intervention studies targeting negative emotions have been mixed, suggesting that these causal relationships may be heterogeneous at the individual level. Identification of individual patterns of negative emotions and BN behaviors can be used to more accurately identify the causal relationships that perpetuate eating disorder behaviors. We used causal discovery analysis of the EMA data to identify the causal network structure that best fits individual data from adults with BN.

Methods:To examine individual causal relationships, we analyzed data from 128 adult women with at least 60 EMA data points collected over 14 days. EMA data included measures of negative/positive affect, anger/hostility, binge eating, vomiting, and exercise. We use the Greedy Fast Causal Inference (GFCI) algorithm to learn the partial descent plot and compute a hypothetical causal model for each participant from their data. A structural equation model was used to estimate effect sizes for each model. Counts of the number of unbiased causal edges between variables of interest were calculated for all participants.

Results:In 28/128 (22%) of the participants, we found a direct causal association with high negative affect before the binge. Other causal associations identified included low positive affect before binge eating: n = 5 (4%), anger/hostility before binge eating: n = 5 (4%), vomiting before binge eating: n = 45 (35%) and binge eating Eat before vomiting: n = 26 (20%).

Conclusions:Previous studies examining negative affect and binge eating in BN were limited by group-level analyses. Through causal discovery, we found that only 22% of participants had a causal relationship between negative affect and binge eating. The causal finding also demonstrated heterogeneity in the sequence of binge eating behaviors, with binge eating occurring both after (35%) and before (20%) self-induced vomiting. Identifying causal models at the individual level may optimize precision medicine approaches in the design of future eating disorder treatment studies.

Key words:Computational Psychiatry, Eating Disorders, Momentary Ecological Assessment, Personalized Medicine

To disclose:Nothing to disclose.

Nhien Nguyen*, Jun Yang, Christophe Morisseau, Dongyang Li, Eileen Lam, J. Bruce German, D. Blake Woodside, Bruce D. Hammock, Pei-an (Betty) Shih

University of California, San Diego, La Jolla, California, USA

Background:Oxylipins are bioactive lipid mediators derived from polyunsaturated fatty acids (PUFAs) via cytochrome P450 (CYP), lipoxygenase (LOX), cyclooxygenase (COX) or non-enzymatic pathways. Soluble epoxide hydrolase (sEH) converts a class of oxylipin-derived CYPs, fatty acid epoxides (epoxides), to the corresponding fatty acid diols (diols). This process modulates important biological processes such as inflammation and metabolism. The gene encoding sEH was previously found to be epidemiologically associated with the risk of anorexia nervosa (AN). This study focused on elucidating the differential effects of sEH, PUFA, and oxylipins measured directly on AN risk and psychopathology.

Methods:Blood samples from 70 women with AN (age: 32 ± 12) and 96 age-matched control women (age: 29 ± 8) were analyzed fasting and 2 hours after consumption of a high-fat study meal. Fasting and postprandial levels of 59 oxylipins from CYP, LOX, COX and non-enzymatic pathways, sEH protein expression and enzyme activity, and 13 diol/epoxide ratios (as markers of sEH activity in vivo) were examined. Clinical phenotypes of AN were assessed using EDI-3 and EDE-Q (Eating Disorder Severity Scales), anxiety, depression and food aversion. Statistical analyzes were performed using t-tests and covariate-adjusted models.

Results:Seventeen fasting oxylipins (29% of 59 tested), derived primarily from n-6-arachidonic acid (ARA, n =9) and n-3-docosahexaenoic acid (DHA, n =7), were compared with controls (all p < 0.01). CYP pathway oxylipins (n ​​= 9 epoxides and 3 diols, 38% of total CYP oxylipins) were reduced by 30-60% in AN, whereas 5 LOX oxylipins (29% of total LOX oxylipins) were reduced by 42%. by 82%. At the postprandial time point, levels of 6 oxylipin CYPs (19% of total oxylipin CYPs) and 3 oxylipin LOX (18% of total oxylipin LOX) were significantly different between groups. In AN, CYP epoxides significantly increased, while CYP diols and 3LOX oxylipins decreased compared to controls (all p<0.05). Significant differences were found between groups in changes in oxylipin levels for 10 CYP epoxides (31% of total oxylipin CYPs) (all p < 0.03), all of which were increased in AN (range: 1 to 48 nmol/ L), but decreased (range: -2 to -306 nmol/L) in post-meal controls. Oxylipin LOX increased in both groups, but to a significantly greater degree in controls (p = 0.02).

In AN, of the 17 fasting oxylipins associated with AN risk, none of the CYP epoxides were significantly associated with psychopathology using the EDI-3 and EDE-Q scores. However, the n-6-ARA (5,6-DiHETrE)-derived CYP diol was associated with greater psychopathology on 5 of the EDI-3 scale scores, whereas the n-3-DHA (10,11- and 4,5-DiHDPE) were associated with lower disorder severity, depression, and food aversion (all p<0.05). LOX pathway 11- and 15-HETE were associated with a less severe perfectionism score, whereas 5-HETE was associated with a higher interoceptive deficit score (all p < 0.05). None of the oxylipins was significantly associated with anxiety, neither in AN nor in controls.

sEH protein expression and enzyme activity were 16% (p = 0.04) and 22% (p = 0.01) greater than controls in AN isolated at the time of fasting. After feeding, sEH expression and activity increased by 56 and 63% in AN (p < 0.05) and 111 and 155% in controls (p < 0.10). None of the fasting oxylipin ratios (in vivo marker of sEH activity) differed significantly between groups. At the postprandial time point, 7 oxylipin ratios (54%) were 44 to 75% lower in AN compared to controls (all p<0.05). sEH oxylipin expression, activity, and proportions were not significantly associated with EDI-3 or EDE-Q scores.

Conclusions:sEH affects human health by converting PUFA-derived epoxides to their metabolites, dioloxylipins. The association between sEH and AN was previously established at the genome level. Here we present further evidence linking sEH to AN risk, showing differential associations between sEH substrates (epoxides) and products (diols) with AN risk and PUFA class-dependent phenotypes. Direct measurement of sEH expression and activity confirmed a higher level of sEH in AN. Significant differences between groups in meal-induced changes in oxylipin were characterized by opposite changes in sEH substrates (epoxides), which increased in AN but decreased in controls. Surprisingly, although both epoxide and dioloxylipins were associated with AN risk, only diols were associated with AN phenotypes. Furthermore, n-6 diols were associated with impaired AN phenotypes, while n-3 diols were associated with better AN phenotypes. Our results confirmed the role that sEH plays in modulating not only AN risk but also eating disorder severity. The effect of sEH on oxylipin n-3 PUFA compared to oxylipin n-6 PUFA resulted in different effects on AN phenotypes, highlighting the importance of considering the source of PUFA in sEH studies and the potential for specific leadership in nutrition in the future.

Key words:Metabolites, polyunsaturated fatty acids, anorexia nervosa

To disclose:Nothing to disclose.

Blair Uniacke*, Karin Foerde, Monica Jablonski, Kenneth Wengler, Guillermo Horga, Jonathan Posner, Joanna Steinglass

Columbia University, New York State Psychiatric Institute, New York, New York, United States

Background:Anorexia nervosa (AN) is a devastating illness that occurs most frequently during adolescence and has one of the highest mortality rates of any psychiatric disorder. Several previous studies have identified altered dopamine function in AN, suggesting that abnormalities in the dopamine system may play a role in the pathophysiology of persistent maladaptive nutritional restriction in AN. Although previous studies using positron emission tomography (PET) and lumbar puncture to assess the metabolic by-products of dopamine metabolism (eg, homovanillic acid) generally suggest dopamine dysfunction in AN, the nature and direction of this disorder have not been elucidated. This knowledge gap may have arisen, at least in part, because AN frequently occurs and sets in during adolescence, when the use of in vivo assessments of dopamine function, such as PET or lumbar puncture, has limited appeal. due to invasiveness, ethical considerations, cost, and methodology. Neuromelanin-sensitive magnetic resonance imaging (NM-MRI) is a high-resolution neuroimaging technique that provides a non-invasive, indirect measure of dopamine function by measuring the concentration of neuromelanin, a byproduct of dopamine metabolism, in the substantia nigra (SN) ) and the ventral tegmentum. zone (VTA). This ongoing study examines dopamine in the SN and VTA in adolescents with AN compared to healthy adolescents (HC).

Methods:MN-MRI data were collected from 14 postmenarcheal adolescents with AN and 10 HC (14 to 18 years old); data collection is in progress. The extracted neuromelanin (NM) signal (contrast-to-noise ratio) was calculated over the SN pars compacta (SNpc; SN region with the highest concentration of DA neurons) and VTA. Independent-samples t-tests were used to compare differences between groups and Hedges' g to measure effect size.

Results:Compared to HC participants, adolescents with AN had a lower NM signal within the SNpc (t1.22 = 2.07, p = 0.05; g = 0.86). Preliminary analyzes also indicate a lower MN signal in the VTA (t1.12.5 = 2.0, p = 0.067; g = 0.91), although this result does not reach significance in this small sample.

Conclusions:Neuromelanin-sensitive magnetic resonance imaging (NM-MRI) is an indirect, non-invasive, validated measure of dopamine function. Our results indicate a lower magnetic resonance signal in the substantia nigra of adolescents with AN compared to healthy adolescents, suggesting reduced midbrain dopaminergic function in AN. NM-MRI may provide a non-invasive approach to measuring dopamine function that can be safely and routinely used in pediatric and non-pediatric populations with AN. Investigating the relationship between midbrain magnetic resonance imaging (MRI) signal and disease stage, severity, and course through longitudinal assessment in adolescents with AN will be a fruitful avenue for future research.

Key words:Anorexia Nervosa, Dopamine, Human Neuroimaging

To disclose:Nothing to disclose.

Mariel Lepra*, Joeffre Braga, Blake Woodside, Stephen Kish, Pablo M. Rusjan, Thomas Chao, Michael Bagby, Stefan Kloiber, Ishrat Husain, Jeffrey Meyer

Centre for Addiction and Mental Health, University of Toronto, Toronto, Canadá

Background:Anorexia nervosa (AN) has a lifetime prevalence of approximately 0.8% and is possibly the deadliest psychiatric disorder in the world, with a mortality rate 5.86% higher than in the general population. Unfortunately, there are no drugs with indications for this disease and no therapeutic targets for AN in the brain.

It is currently unknown whether gliosis occurs in AN, but there are several plausible reasons why it might occur. Peripheral inflammation can cause gliosis, and there is evidence that more peripheral inflammation can occur episodically in AN. Anorexia nervosa occurs with prevalence rates of up to 20% in children with pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections and acute neuropsychiatric syndrome in children. The prevalence of autoimmune diseases that can lead to gliosis is approximately 2 times higher in AN. Inducing peripheral inflammation in humans, such as B. by vaccination or administration of lipopolysaccharide, the latter also increases gliosis-marker translocator protein (TSPO) in the brain, induces the symptom of anorexia, and direct cerebral inflammatory stimulation in rodents also induces anorexia. Furthermore, inverse relationships between body mass index (BMI) and TSPO VT, an index of translocator protein density and gliosis, have been frequently reported in neuropsychiatric disorders.

TSPO VT can be measured with [18F]FEPPA, a radiopharmaceutical with excellent properties for use in positron emission tomography (PET) imaging. We hypothesize that TSPO VT will be elevated in circuits involved in AN, including the anterior cingulate cortex (ACC), insula, dorsal putamen, dorsal caudate, orbitofrontal cortex (OFC), ventral striatum, and thalamus.

Methods:Eleven AN (9F, 2M, mean age 25.09) not treated with antidepressants, antipsychotics, or anti-inflammatories and eleven healthy controls (8F, 3M, mean age 25.82) underwent [18F]FEPPA. arterial sampling. Exclusion criteria were smoking and substance use disorders. A two-tissue compartment model was applied to measure TSPO VT. Regions of interest included ACC, insula, dorsal putamen, dorsal caudate, OFC, ventral striatum, and thalamus. Groups were compared using repeated measures ANOVA (rmANOVA), where group (healthy or AN) was the independent variable and the range of interest was the repeated measure. ANOVAs comparing individual regions between groups were also performed. The genotype of a single nucleotide polymorphism of the TSPO gene (rs6971) was used as a factor in all analyses.

Results:There was interaction between group and regions selected a priori, indicating that some regions were more different between groups than others (rmANOVA, p = 0.04). ANOVAs comparing individual regions between groups found higher TSPO VT in ACC (32% difference, F1.19 = 8.1, p = 0.01) and thalamus (41% difference, F1.19 = 7.2, p = 0.01).

Conclusions:To the best of our knowledge, this is the first study of gliosis in AN. Differences in TSPO-VT are most pronounced in the anterior cingulate cortex and thalamus, implying that gliosis in these regions is greater in AN. This suggests that anti-inflammatory approaches should be considered for development as a treatment in AN and these two regions should be a focus for future studies of inflammatory processes in AN.

Key words:Anorexia nervosa, TSPO, positron emission tomography, gliosis, eating disorders

To disclose:Nothing to disclose.

Wenchao Zhang, Guanya Li, Yang Hu, Jia Wang, Weibin Ji, Gang Ji, Peter Manza, Dardo Tomasi, Nora Volkow, Yi Zhang, Gene-Jack Wang*

National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland, USA.

Background:Obese (OB) people are more likely than normal-weight (NW) people to prefer the immediate reward of food intake to the delayed reward of healthy well-being achieved through controlled diet and physical activity. This may reflect intertemporal decision-making deficits and increased impulsivity. Overeating as a result of increased impulsivity is a major contributing factor to the development and maintenance of obesity. Laparoscopic sleeve gastrectomy (LSG) is one of the most effective treatments for morbid obesity and results in sustained weight loss. In addition, LSG improved problem and disturbed eating behaviors such as B. It improved control of food intake and reduced the frequency of snacking on high-calorie foods. However, it is unclear whether this improved eating behavior was associated with reduced impulsivity in OB after LSG and how LSG regulates associated brain functions. Therefore, the current study used functional magnetic resonance imaging (fMRI) with a monetary delay (DD) discount task to examine LSG-induced changes in impulsivity and their neural correlates.

Methods:Twenty-nine OBs underwent whole-brain fMRI with DD task before (PreLSG) and one month after LSG (PostLSG). Thirty sex- and age-matched OB participants were recruited as controls and subjected to the same fMRI. As a measure of impulsivity, the discount rate (K) was quantified based on the hyperbolic function and the area under the curve (AUC), which is independent of theoretical assumptions about the discount function. As the discount rate did not follow a normal distribution, the log-transformed K (lg(K)) was calculated. Pre-processing of fMRI data was performed with Statistical Parametric Mapping 12. In the present study, two different statistical analyzes were performed using the General Linear Model (GLM). First, a GLM with hard-choice and easy-choice regressors was constructed for each participant, with hard choices defined as those with similar subjective values ​​for immediate and deferred reward options. Second, we create a GLM for each participant that includes SIRs (options for smaller immediate rewards) and LDRs (options for larger delayed rewards). Individual beta images responding to Hard/Easy options, SIR/LDR conditions, and contrast images for Hard-Easy and LDR-SIR were then calculated. To examine differences in activation between PreLSG and PostLSG, we performed a second-level analysis (paired t-tests) on these beta and contrast images. Clusters with significant differences between PreLSG and PostLSG were selected as regions of interest (ROI). In addition, a whole-brain psychophysiological interaction (PPI) analysis was performed to examine changes in choice difficulty and functional connectivity related to subjective choice using these ROIs as seeds. We also performed two-sample t-tests to compare brain activations and functional connectivity between NW and LSG groups (PreLSG and PostLSG).

Results:LSG significantly reduced the discount rate on OB. During rigorous trials of the DD task, LSG significantly decreased and increased activations in the left dorsolateral prefrontal cortex (DLPFC) (Brodmann's area (BA) 9), dorsomedial prefrontal cortex (DMPFC), which averaged in NW, in addition to activations. in bilateral posterior insula (INS). Changes in left DLPFC activation were negatively correlated with changes in cognitive control as measured by the three-factor dietary questionnaire (TFEQ, r=-0.549, P=0.004) and AUC (r=-0.484, P=0.010). 🇧🇷 Changes in left DMPFC activation were positively correlated with changes in hunger (TFEQ) (r = 0.513, P = 0.005). Changes in bilateral INS activation were negatively correlated with changes in body mass index (BMI) (r = -0.551, P = 0.002) and disinhibition (TFEQ, r = -0.464, P = 0.011). Furthermore, LSG significantly reduced activations in the left DLPFC (BA46) and right caudate during the SIR condition, which on average was equivalent to NW. Changes in left DLPFC activation were positively correlated with changes in BMI (r = 0.555, P = 0.002), Ig(K) (r = 0.467, P = 0.012) and negatively correlated with changes in cognitive control (TFEQ , r = - 0.522). , P = 0.004), AUC (r = -0.460, P = 0.012). In the PPI analysis, there was greater functional connectivity between the right caudate and the left DMPFC (BA32) in response to choosing LDR versus SIR in PostLSG compared to PreLSG and NW. Changes in functional connectivity between the right and left caudate DMPFC were positively correlated with changes in cognitive control (TFEQ, r = 0.588, P = 0.001) and negatively correlated with changes in disinhibition (TFEQ, r = -0.540, P = 0.004).

Conclusions:These results suggest that reduced impulsivity after LSG was associated with normalization of activation in regions involved in executive control and reward appraisal, and the compensatory effects of increased interoception and prospecting. This study may provide neurophysiological support for the development of non-surgical treatments such as brain stimulation for obese and overweight patients who do not qualify for LSG.

Key words:Obesity, fMRI task, obesity surgery

To disclose:Nothing to disclose.

Sasha Gorrell*, Megan Shott, Guido Frank

University of California, San Francisco, San Francisco, California, USA. UU.

Background:Anorexia nervosa (AN) is a severe and often chronic psychiatric disorder of unknown etiology. Recent evidence from the monetary and taste reward paradigms examining reward prediction error suggests that dysregulation in reward processing may sustain symptoms and create a vicious cycle that contributes to chronicity and frequent relapses. However, whether expecting and receiving a conditioned reward can predict long-term outcome has not been studied directly. Here, we followed people treated for AN and tested whether brain imaging reward response could predict BMI. We hypothesize that higher neuronal activity in relation to expectation (greater arousal) and response error prediction (greater dopamine-related reward response) predicted lower BMI (less treatment response) at one-year follow-up.

Methods:The sample included a subset of a larger study of young adult patients with AN receiving treatment for eating disorders in a specialized subhospital or inpatient program (n = 35, Mage [SD] = 23 [7]). Functional brain imaging was used to assess brain response during a classical conditioning paradigm in which violations of learned associations between conditioned visual stimuli and unconditioned gustatory stimuli caused the dopamine-related prediction error. The brain images were analyzed both for the expectation of the caloric stimulus and for the prediction error response, which consisted of unexpected receipt or omission of the sucrose caloric gustatory stimulus. Regional brain response data were extracted for the insula, orbitofrontal cortex and striatum. Study participants were contacted after discharge from the treatment program for long-term follow-up.

Results:Follow-up examination was performed 1648 days (SD ± 1198) after brain imaging. Mean follow-up BMI = 18.9 (SD ± 3.3); Mean BMI variation between assessment points = 2.5 (SD ± 3.2). Patient Self-Report Eating Disorders Examination Questionnaire (EDE-Q) reluctance = 2.2 (SD ± 1.9), concern about eating = 2.3 (SD ± 1.3), concern about shape = 3 .2 (SD ± 1.5) and weight concern = 2.9 (SD ± 1.7); Participants also rated their mood (Beck Depression Inventory [BDI] = 20.2 [SD ± 12.9]) and anxiety (State/Trait Anxiety Index [STAI] = 49.3 [SD ± 12.9] 3]). Long-term follow-up BMI was positively correlated with BMI at discharge (r = 0.59, p < 0.001) and days after examination (r = 0.44, p = 0.009). Adjusted for multiple comparisons, no significant associations were found for prediction or expectation error and follow-up BDI, STAI, or EDE-Q scores. A pattern emerged in which significant associations (at p < .05) in activity associated with prediction errors and follow-up BMI were positive, whereas associations in activity related to expectation and long-term follow-up BMI were negative. Adjusted for multiple comparisons (p < .001), a significant correlation was maintained only for expectancy-related activity in the right superior orbitofrontal cortex with BMI, r = -.58, p < .001, 95% CI = [ 0.77, 0.31].

Conclusions:The results show that the expectation, but not the forecast error, is related to the results of the weights. The study suggests that the expectant response in the superior orbitofrontal cortex may be particularly important for long-term outcome. The superior orbitofrontal cortex is part of the superior frontal gyrus and is involved in executive function and inhibitory control, as well as in the regulation of mood and personality traits. The superior orbitofrontal cortex may be mechanically involved in the persistent and cognitive-emotional aspects of AN and may be a biomarker of long-term outcomes.

Key words:Anorexia nervosa, reward expectancy, superior orbitofrontal cortex

To disclose:Nothing to disclose.

Guido Frank*, Megan Shott, Skylar Swindle, Tyler Nguyen, Tamara Pryor, Joel Stoddard

University of California San Diego, San Diego, California, USA

Background:Anxious traits are increased in eating disorders (ED), they are considered risk factors for the development of ED, and trait anxiety has been associated with the psychopathology of ED. It is not well understood how trait anxiety relates to the neurobiology of erectile dysfunction. Here, we examined a transdiagnostic study sample across the ED spectrum to assess the response to expectation of a caloric stimulus (sucrose) and anticipated reception, both in contrast to a non-caloric taste stimulus and the effects of anxious traits. Our hypothesis is that the increase in trait anxiety in individuals with eating disorders would be associated with the brain's response to the anticipation and reception of caloric gustatory stimuli. The amygdala is a central brain region for anticipation, alertness, fear and threat. We expected that the ED sample would show a greater amygdala response to anticipation of a high-calorie sucrose solution stimulus compared to the non-caloric stimulus, and that the anticipation response would negatively affect and reduce response in brain reward regions. . during early taste reception, which could interfere with food intake.

Methods:In this study, 179 subjects across the ED spectrum (anorexia nervosa n=91; other specified EDs n=34; bulimia nervosa n=56; binge eating EDs n=16) and 120 healthy controls were examined for features anxious. and learning and expectations. receive caloric or neutral gustatory stimuli during functional magnetic resonance imaging of the brain. We developed first-level models to predict the response in each voxel based on the following conditions: (1) Sucrose expectancy: CS experiments predicting sucrose absorption versus CS experiments using artificial saliva (non-caloric gustatory stimuli). 🇧🇷 (2) Expected sucrose absorption: Studies with expected US caloric absorption of sucrose were compared with studies with expected US caloric absorption of artificial saliva. We extracted beta values ​​from predefined regions of interest bilaterally. Group comparison studies were performed with and without potentially confounding group comparison covariates (MANOVA or MANCOVA for estimated marginal means). Regression analyzes tested associations between behavior and brain activation. A moderator analysis (PROCESS, SPSS) was used to test the effects of fear on the relationship between amygdala expectant response to sucrose (X) and reward circuit taste reception response (Y). Results were multiple comparisons controlled by false detection rate (FDR).

Results:Amygdala sucrose expectancy response differed between groups (Wilks lambda = 0.945, p = 0.023) and was greater in left anorexia nervosa than in healthy controls (p = 0.002). The expected sucrose uptake response in the taste reward regions did not differ between groups. In the ER sample, trait anxiety negatively moderated the relationship between amygdala expectation and right dorsal (p = 0.0062) and ventral (p = 0.0046) anterior insular reception responses. A subgroup analysis showed similar results for anorexia nervosa and partly for bulimia nervosa. In all NDs, appetite motivation was positively correlated with bilateral orbitofrontal cortex, tail head, and ventral striatum sucrose reception response (r = 0.215 to 0.179, p = 0.002 to 0.012). Across the study sample, trait anxiety showed an inverted U-shaped relationship with right (r = 0.147, p = 0.034) and left (r = 0.162, p = 0.016) amygdala expectant response.

Conclusions:A greater amygdala response in combined AN and ED samples suggests greater arousal to food stimuli. The relationship between amygdala expectation and right islet stimulus response is moderated by trait anxiety in individuals with eating disorders. The influence of the fear trait on the brain's gustatory response supports the notion that fear traits interrupt normal reward and interoceptive processing and therefore may play an important role in maintaining the pathophysiology and psychopathology of erectile dysfunction. The study raises the question of whether altering the effects of trait anxiety and related arousal through psychopharmacological or psychotherapeutic interventions could play an important role in facilitating targeted treatment of erectile dysfunction.

Key words:Eating disorders, anorexia nervosa, reward expectation, anxiety

To disclose:Nothing to disclose.

Stephanie Dulawa*, Jie Zhang, Rizaldy Zapata, Avraham Libster, Olivia Osborn

University of California – San Diego, La Jolla, California, USA

Background:Anorexia nervosa (AN) occurs predominantly in girls and women and is characterized by hypophagia, dangerously low body weight, and compulsive exercise. Recent large-scale studies of the human genome have shown that AN has an important metabolic component. Other recent studies point to adipose tissue as the site of "metabolic memory" of previous nutritional states. Activity-based anorexia (ABA) induces certain aspects of AN in rodents; The mice are simultaneously subjected to rolling wheels and programmed feeding, which induces hypophagia, weight loss and hyperactivity. Here, we tested the hypothesis that transplantation of adipose tissue from obese mice fed a high-fat diet (HFD) into recipient mice would attenuate ABA-induced weight loss in recipients, possibly due to diffusible factors released from obese adipose tissue.

Methods:Nine-week-old mice received an intra-abdominal peritonadal fat graft harvested from mice fed a regular chow or obese mice fed a high-fat diet (n = 21/group). All donors and recipients were female C57B1/6 mice. Four weeks after surgery, recipient mice were tested in the ABA paradigm. All mice were acclimated to solitary confinement and constant access to running wheels for 2 days. The mice then entered a basal phase (4 days) in which food and exercise wheels were continuously available. Finally, the mice entered a restriction phase (14 days) in which racing wheels were continuously available, but food was only available 3 hours a day, starting at 09:00. Body weight, food intake and distance walked were measured daily. During restriction, mice were withdrawn from the study (referred to as dropouts) after losing 25% of their initial body weight. The number of restriction days before termination provided a measure of survival. Finally, the same experiment was performed with a new cohort, but inside metabolic chambers (n = 7/group). Additional dependent measurements were VO2 (volume of oxygen consumed, mL/kg/h), VCO2 (volume of carbon dioxide produced, mL/kg/h), respiratory quotient (RQ), food and water intake, body weight, and activity (bar x, bar y, booster counter).

Results:In the first study, no differences in body weight, food intake or cycling were observed between obese control recipients and obese obese recipients during baseline. However, during the restriction phase, obese recipients remained longer in the ABA paradigm than obese controls (p < < 0.01). Despite the increase in survival time seen in obese recipients, there were no differences in body weight, food intake or cycling between groups. In the study of the Metabolic Chamber, no different measures were found between the groups.

Conclusions:Our results show that transplantation of adipose tissue from obese mice fed a high-fat diet (HFD) into recipient mice increases survival time in the ABA paradigm, defined as maintenance of >75% of baseline body weight. These results are consistent with the hypothesis that diffusible factors released by obese adipose tissue impede weight loss. Studies are ongoing to investigate the mechanisms underlying this effect.

Key words:Food intake, cycling, body weight, energy metabolism, transplantation

To disclose:Nothing to disclose.

Priyanka Das, Michaela Cooke, Angela Kim, Kate Callahan, Yan Li, Vadim Bolshakov, Kerry Ressler, Rachel Ross*

Albert Einstein College of Medicine, Bronx, New York, USA

Background:The melanocortin-4 receptor (MC4R) is involved in metabolism and energy expenditure, and MC4R mutations are strongly associated with obesity in humans and mice. Its activity is regulated by peptides released from arcuate feeding and satiety neurons, agouti-related protein (AgRP) and pro-opiomelanocortin (POMC). MC4R is highly expressed in the hypothalamus, but deletion of MC4R from this region does not recapitulate global obesity induced by cerebral deactivation, suggesting that MC4Rs in other regions are involved. The MC4R is expressed in the infralimbic (IL) cortex, an area of ​​the brain involved in decision-making and habitual activity. Human imaging data implicate this region in responses to obesity-related food stimuli. We hypothesize that IL-MC4R (IL-MC4R) activity is regulated by peptides released from hypothalamic neurons and also affects food intake and foraging behavior.

Methods:We used a combination of genetically engineered mice (male and female) with viral vectors to manipulate projections of molecularly defined melanocortinergic arcuate neurons (AgRP and POMC) in the terminal region of the infralimbic prefrontal cortex (IL), as well as the MC4R expressing neuron. in direct LI. We used cutting electrophysiology to probe the pharmacological role of MC4R in IL and immunohistochemistry to further define the molecular identity of these ILMC4R neurons.

Results:We found that MC4R agonists applied to the disks depolarized the membrane and increased the excitability of IL-MC4R neurons. These neurons are also glutamatergic and project to areas associated with food-motivated behavior. Through optogenetic manipulation, we found that stimulation of the AgRP axon terminal in IL acutely increases food intake. Lastly, we used Cre viral manipulation in male MC4Rlox/lox mice to selectively knock out IL-MC4R and observed an increase in food intake and body weight and a delay in feeding and feeding behavior in an open field environment.

Conclusions:Our data highlight a new population of neurons expressing MC4R in the IL that receive functional information from hypothalamic feeding neurons and influence foraging and other foraging behaviors.

Key words:Neuroendocrine, Eating disorders, Melanocortin, Infralimbic cortex, Food intake

To disclose:Nothing to disclose.

Ames Sutton Hickey*, Sean Duane, Laura Mickelsen, Ahmed Shamma, Anna Skillings, Chia Li, Michael Krashes

National Institutes of Health, Bethesda, Maryland, USA.

Background:Anorexia nervosa (AN) is a debilitating and fatal illness characterized by a low body mass index due to reduced food intake and often concomitant hyperactivity. A high percentage of the behavioral and metabolic phenotypes of AN can be replicated in rodents with voluntary access to a running wheel and subjected to a dietary restriction called activity-based anorexia (ABA). Despite the well-documented body weight loss seen in human patients with AN and ABA rodents, much less is known about the neurobiological basis of these maladaptive behaviors. Hunger-promoting hypothalamic agouti-related peptide (AgRP) neurons have been well characterized in their ability to regulate appetite, but much less is known about their activity and role in mediating food intake during ABA.

Methods:C57Bk6, AgRP-iCre, AgRP-iCre::hM3Dq, AgRP-iCre::hM4Di females or littermates (n=3-11) were used in these studies. Mice were individually housed and assigned to one of three behavioral groups (Activity, FR, ABA) with ad libitum (Activity) or time-limited (FR, ABA) access to food and a voluntary running wheel (Activity, ABA only) . Access to food in the FR and ABA cohorts was restricted to the first 3 hours of the dark cycle. Feeding information was collected using FED3 devices, and detection or manipulation of neural circuits was performed using in vivo fiber photometry and chemogenetics, respectively.

Paired t-tests, unpaired t-tests, one-way ANOVA followed by post hoc Bonferroni tests (if applicable), two-way ANOVA followed by post hoc Bonferroni tests (if applicable), or mixed two-way ANOVA followed by post hoc Bonferroni hoc tests (if applicable) Hoc tests (if applicable) were calculated as needed. The normality and homogeneity of the variances were tested and, when appropriate, taken into account using the Shapiro-Wilk or Levene test. Significance was determined at p < 0.05.

Results:We show that ABA mice have decreased food intake due to increased tablet interval recovery and decreased number of meals. Longitudinal activity recordings of AgRP neurons in ABA animals revealed a maladaptive inhibitory response to food. We then show that the development or progression of ABA via AgRP chemogenetic activation can be mitigated by reprioritizing food intake (increased number of meals) over hyperactivity, but only during periods of food availability.

Conclusions:Together, we established the unique capacity, requirement, and circadian period required for AgRP neurons to increase ABA despite weak neuronal activity responses to food. These results highlight a potential neural target to improve behavioral maladaptions present in patients with AN.

Key words:Eating behavior, hypothalamus, hyperactivity, gagging, eating disorders

To disclose:Nothing to disclose.

María José Olvera Caltzontzin, Darielle Lewis-Sanders, Yang-Sun Hwang, Sarah Stern*

Max-Planck-Institut, Jupiter, New York, USA.

Background:Food intake is a complex motivated behavior that is modulated by homeostatic and non-homeostatic factors. Changes in eating behavior can lead to increased consumption leading to obesity and decreased eating in anorexia nervosa. Both cases have profound clinical implications and have been largely untreatable to pharmaceutical intervention. We recently identified the insular cortex as a brain region involved in controlling learned eating behaviors that may contribute to obesity and eating disorders. Specifically, neurons #1 in the insular cortex were required for the expression of a learned overdrive task. However, little is known about how neurons in insular cortex #1 encode food-related behaviors and the mechanism by which they control overeating. Here, we use a combination of chemogenetics and calcium recording to gain a comprehensive understanding of how Nos1 neurons contribute to non-homeostatic dietary changes.

Methods:Nos1-Cre mice (n = 6-10) were injected into the insular cortex with a cre-dependent virus expressing the DREADD inhibitor, hM4Di (AAV-FLEX-hM4Di-mCherry). Mice were tested on a variety of tasks, including learned overeating, conditioned taste aversion, fear tasks (light-dark box, enhanced null maze, suppressed new eating), and object recognition memory. Mice were also tested on homeostatic feeding of regular chow and savory chow (eg Certain). Both mCherry controls and mice expressing hM4Di were injected with saline or CNO 30 min before testing. A separate cohort of Nos1-Cre mice (n = 4–6) were injected with a cre-dependent virus expressing the calcium reporter GCaMP in the insular cortex and an optical fiber was implanted over the injection. Calcium recordings were made with the Neurophotometrics fiber photometry system during the mentioned tasks, and the data were analyzed with custom scripts in Matlab and Python.

Results:Inhibition of insular cortex neurons n. Number 1 resulted in behavioral changes only in associative learning and feeding tasks. Surprisingly, although inhibition of Nos1 neurons prevented learned binge drinking, it increased conditioned taste aversion. Thus, we tested whether Nos1 neurons lead to increased anxiety or impaired memory, but did not observe changes in anxiety-related behavior, object recognition memory, palatability, or homeostatic nutrition. Therefore, we used fiber photometry recordings to correlate Nos1 activity with behavior. We found strong correlations between activity #1 and food consumption, but no correlation with focus or study of food. We also found increased activity in Nos1 neurons when the mice were placed in a new context and exposed to new noxious odors.

Conclusions:We found that Nos1 neurons are specifically involved in controlling the expression of learned eating behaviors, but not in fear, memory or homeostatic nutrition. Likewise, its calcium activity is closely related to binge eating and olfactory and contextual cues that may be important in associating cues with food availability. Thus, through Nos1 neurons, the insular cortex can control complex top-down feeding behaviors.

Key words:Island crust, no. 1, Fressverhalten

To disclose:Nothing to disclose.

Gregory Simandl*, Evan Hess, Linghai Kong, Sarah Kassel, Nicholas Raddatz, Brian Maunze, Qing-song Liu, Sujean Choi, David Baker

Biomedical Sciences, Marquette University, Milwaukee, Wisconsin, USA.

Background:Previous work has implicated xc-system-mediated glutamate (Sxc) signaling between astrocytes and neurons in drug seeking and other forms of maladaptive behavior. Here we examine which forms of cognition are dependent on Sxc and how neurons regulate glutamate release from astrocytes to allow for sophisticated cognitive control of behavior. We hypothesize that pituitary adenylate cyclase activating polypeptide (PACAP) is released from corticostriatal inputs to the nucleus accumbens, where it regulates signaling from astrocytes to neurons to allow cognitive control over behavior.

Methods:Mouse afferent and efferent nucleus accumbens were labeled by injection of the retrograde neural tracer cholera toxin b into the nucleus accumbens and substantia nigra/ventral pallidus, respectively. Fluorescence activated cell sorting was used to isolate astrocytes, efferent and afferent nucleus accumbens. mRNA was measured using PCR or in situ hybridization. The xc system-dependent release of glutamate from nucleus accumbens astrocytes was measured using a cystine-induced glutamate release assay coupled to reverse-phase HPLC. Neural activity in neurons in the middle column of the nucleus accumbens was measured using slice electrophysiology. Cocaine self-administration and initiated reintroduction were performed using a long-access protocol (12 days). Working memory, impulsivity, decision making and cognitive flexibility were measured using Bussey-Saksida touch screens.

Results:Mutant mice without Sxc (MSxc mice) show significant deficits in decision-making in the rodent game task (N = 10/genotype; session x genotype x stimulus: F42.1008 = 1.387, p < 0.05), cognitive flexibility in the paradigm shift ( N = 6-7/genotype experiments in criterion: extradimensional shift: t11 = 0.3.83, p < 0.05 * relative to WT interdimensional shift: t11 = 2.96, p < 0, 05 * relative to WT persistent error: t11 = 3.39, p < 0.01), increased impulsivity in the 5-choice series reaction time task (N = 6-7 /genotype; t11 = 2.217, p < 0.05), increased levels of punished behaviors in Pavlovian conditioning (N = 9 - 10/session genotype: F4.68=7.633, p<0.05 genotype: F1.68 =6.187, p<0.05) and cocaine-initiated resumption (N = 13/genotype, t11 = 3.26, p < 0.05 * relative to weight). We also show that PACAP is expressed in inputs to the nucleus accumbens of the prefrontal cortex and that PACAP increases glutamate release from Sxc- in astrocytes of the nucleus accumbens (N = 6-12/genotype; genotype: F1.40 = 275,645, p < 0.05, treatment: F3.40 = 4.492, p < 0.05, genotype x treatment: F3.40 = 4.003, p < 0.05). To our surprise, we also found that PACAP acts on PAC1R expressed in MSN to remove the magnesium blockade of NMDA receptors containing GluN2B, allowing these receptors to be activated by glutamate released by Sxc. Finally, intranucleus accumbens PACAP signaling blocks cocaine-induced reuptake (treatment: F1.18=13.03, p<0.05; test procedure: F1.18=45.89, p<0.05; treatment x test method: F1.18 = 13.82, p< 0.05), and this effect requires intact NMDA receptor activity containing Sxc and GluN2B (treatment: F3.52 = 5.646, p<0.05; genotype: F1 .52 = 3.666, p > 0.05; treatment x genotype: F3, 52 = 10.148, p < 0.05).

Conclusions:PACAP is expressed at corticostriatal inputs to the nucleus accumbens and enables a form of astrocyte-to-neuron signaling by enhancing glutamate release from Sxc and allowing activation of NMDA receptors containing GluN2B. The consequence of PACAP-activated astrocyte signaling to neurons is better behavioral control, leading to reduced addiction to cocaine-based drugs only when Sxc- is intact. The next steps will be to determine whether PACAP release from corticostriatal inputs regulates Sxc-mediated signaling-dependent behaviors between astrocytes and neurons.

Key words:Glutamate, astrocytes, PACAP, cognitive control

To disclose:Nothing to disclose.

Julianna Cavallaro, Jenna Yeisley, Ruby Setara, Joseph Floeder, Basak Akdogan, Peter Balsam, Eduardo Gallo*

Fordham University, Bronx, New York, USA

Background:Impulsive decision-making, often characterized by an excessive preference for small, short-term rewards over larger, long-term rewards, is a prominent feature of substance use and other neuropsychiatric disorders. A growing body of evidence suggests that nucleus accumbens dopamine (NAc) and its effects on D2 receptors (D2R) are involved in various forms of impulse control. Because multiple NAc and afferent cell types express D2Rs, it has been difficult to determine the specific neural mechanisms that link NAc D2Rs to impulsive choice. Among these cell types, cholinergic interneurons (CINs) expressing D2R are key regulators of striatal plasticity and local dopamine release, but their role in impulsive behavior is unknown. Our recent work has shown that increasing D2R expression specifically in NAc-CIN impairs learning to suppress actions in a Go/No-Go task. While this is consistent with increased action impulsiveness, here we set out to determine the contribution of CIN D2R to impulsive decision making.

Methods:To determine whether elevated levels of D2R in NAc-CINs contribute to impulsive choice, we first inject Cre-dependent adeno-associated virus (AAV) expressing D2R-EGFP or EGFP into the NAc of adult ChAT-Cre- mice (8 mice/ group, both sexes) introduced). Rats were trained in a delay discount task that measures the choice between pressing a lever for a small, immediate reward or pressing another lever for a larger (3X) reward presented after increasing delays. After the sessions in which large and small rewards were delivered immediately after pressing the stick, large reward delays (2, 4, 6, 8, 10 s) were introduced in the sessions in ascending order. We also used a probabilistic discounting task on a separate cohort of ChAT-Cre mice overexpressing D2R or EGFP in NAc-CIN (n = 8 mice/group). Rats were given a choice between a small, safe reward and a large reward that progressively decreased in probability (80, 60, 50, 40, 33, 20%). For both tasks, the mean percentage of decisions made on the "big" lever was analyzed using a two-way repeated measures ANOVA. We selectively inactivated the D2R gene in CIN using ChAT-IRES-Cre x Drd2flx/flx (CIN D2-KO) mice to measure the effect on delay and probability discounting. Next, we determined whether upregulation of CIN D2R changed the representation of time intervals using a maximum interval task. After learning that lever presses were only reinforced after a defined 24-second interval, the mice were given "spike" tests in which lever presses were not reinforced. Individual stick press velocity data (maximum position and width) were used to assess timing accuracy and precision. Furthermore, we tested the ability to correctly categorize two different long tones as short or long (2 x 8 s and 6 x 24 s) using a temporal discrimination task.

Results:In the absence of delays in large or small reward, D2R overexpression and control mice similarly increased their preference for large reward. As Big Reward delays increased, both groups experienced Big Rewards discounts, as evidenced by the reduced selection of Big Rewards. However, this discount was significantly higher in D2R overexpressing mice compared to controls (virus x lag interaction: F(5.70) = 6.13, p<0.05). We then tested whether this manipulation would also change probability discounting, another dimension of impulsive choice in which rewards are discounted as they become more uncertain. Indeed, we found that greater uncertainty in both groups increased discounting (greater choices in small, specific rewards), but there was no significant effect of D2R upregulation. To determine whether D2Rs in CIN are required for impulsive choice, we measured the delay probability discount in CIN-D2KO and control Drd2flx/flx mice. Both groups discounted the large bounty after long delays, but CIN-D2KO was less willing to switch to the small immediate option, indicating a reduced delay discount. In contrast, we found no effect of CIN D2R removal on probability discounting. Furthermore, D2R overexpression and control mice showed comparable response rates and distributions close to the 24 s target in the maximum interval task. The temporal discrimination task also did not show group differences in the correct categorization of long and short sounds, even when the duration was proportionally increased.

Conclusions:Our results show that increasing CIN D2R expression in the NAc results in greater delay discount without changing the probabilistic discount. This is supported by supplemental data from CIN-D2KO mice showing that delay discount, but not probability discount, is reduced compared to controls. These results suggest that D2R CINs encourage impulsive decisions with delayed but not uncertain rewards. As we did not observe group differences in choice when both rewards were delivered immediately, it is unlikely that the delay discounting effect is due to differential sensitivity to reward magnitude. Furthermore, the lack of effect on maximal interval and temporal discrimination tasks suggests that the ability to measure intervals is not fundamentally altered by D2R upregulation. Taken together, these results suggest that dopamine signaling via D2Rs expressed in CIN plays a key role in delay-based impulsive choice, providing new insights into the mechanisms by which the dopamine NAc controls CIN function and regulates impulsive behavior.

Key words:Cholinergic interneuron, dopamine D2 receptor, impulsive behavior, nucleus accumbens, delay discount

To disclose:Nothing to disclose.

Brandy Briones*, Marissa Borrego, Prabhat Aluri, Alondra Torres, Jason Siputro, Garret Stuber

University of Washington, Seattle, Washington, EE. UU.

Background:Navigating new social environments is complex, multisensory, and cognitively demanding, and mammals have very limited initial information to guide their social behavior. In some cases, this can lead to an increased perception of threat and aggression toward an unfamiliar outgroup member, a phenomenon known as ingroup bias. Kinship and familiarity reduce aggression-related interactions in mice, however, the neural circuits and mechanisms involved in in-group and out-group social behavior biases still need to be established. The paraventricular thalamus (PVT) is a critical center for integrating sensory features and emotional state information in novel and aversive contexts. However, the integration of social information into DVT in these contexts and whether steroid hormones regulate DVT activity remain unresolved. Our study identifies a subset of steroid hormone receptor neurons in posterior PVT involved in male outgroup aggression.

Methods:Using a multiplex hybridization chain reaction assay, we characterized sex steroid hormone-related gene expression to identify distinct cell groups in the PVT of male and female mice (n=3 males, n=4 females). Using a strain of Esr1-Cre + /- transgenic mice, we virally targeted these neurons expressing steroid hormone receptors in the PVT to study the role of steroid hormone genes in social behavior. After testing a variety of behavioral tests using optogenetic stimulation (e.g., real-time location preference, open field, elevated plus maze, and free social interaction), we found a male-specific aggression phenotype and focused the remainder of our study on human-to-human aggression in the resident intruder paradigm (group sizes 8-10). In a resident intruder paradigm, we tested male outgroup aggression biases in wild-type mice (n = 8) and recapitulated behavior without optogenetic manipulation.

Results:We analyzed approximately 10,000 cells along the anteroposterior axis of the PVT. Genes related to estrogen and androgen receptors, notably Esr1, Esrra and Rora, were highly expressed in the central and posterior regions of the PVT, which was confirmed by the expression patterns of virally tagged neurons in Esr1-Cre  /- mice. Furthermore, Esr1, Esrra, and Rora were highly co-expressed (>50%) in the same cell population, suggesting that the sex steroid receptor-dependent activity in DVT occurs in the same subset of cells, thus reflecting the Esr1- cre + /- Mouse a viable model to study the modulation of sex steroid hormones in PVT during social behavior. During a resident intruder paradigm, optogenetic activation of Esr1+ PVT neurons in the resident mouse elicited a male-specific aggression phenotype, in which male mice initiated aggressive attacks that were linked to the light stimulus versus mice in the outgroup but not in the intruder group. ingroup (p < 0.05). Furthermore, we observed that approximately 50% of sexually experienced wild-type male C57BL/6 mice exhibited out-of-group but not in-group aggression in the resident intruder paradigm without any optogenetic manipulation. Viral staining of Esr1+-PVT neurons in Esr1-Cre + /- mice also revealed dense projections in the amygdala and enlarged regions of the amygdala, the bed nucleus of the stria terminalis, the ventromedial nucleus accumbens, the insular cortex, and cortices, which provides other goals to further analyze this behavior.

Conclusions:From the data we have collected so far, our results suggest that activation of central and posterior PVT, particularly in subsets of neurons expressing estrogen and androgen receptor-related genes, prevents outgroup aggression. Future directions of our study will aim to examine 1) in vivo PVT neural activity in Esr1+ neurons during free-roaming social behavior, 2) whether estrogen and/or androgen receptors in PVT are required for PVT attack behavior. outgroup and 3) whether circulating hormones alter activity in this neuronal population.

Key words:Paraventricular thalamic nucleus, aggression, in-group bias, sex steroid hormone receptors, fluorescent in situ hybridization

To disclose:Nothing to disclose.

Yui Asaoka, Moojun Won, Emi Ishikawa, Tomonari Morita, Yukiori Goto*

Kyoto University, Kyoto, Japan

Background:Behavioral addictions such as gambling, internet and gambling have been recognized, but their concept and definition have yet to be determined. Some impulse control disorders such as kleptomania and paraphilia have been suggested to meet the criteria for addiction but are not correctly classified as addictive disorders due to insufficient studies to fully understand these disorders as behavioral addictions. In this study, we examined how environmental cues associated with the disorder were processed in patients with kleptomania to gain more insight into this behavioral addiction.

Methods:The images of the grocery store with (MKT+H) and without (MKT-H) a person, those outside with (OUT+H) and without (OUT-H) a person, and those for grocery stores (FOD) and stationery ( STY) Healthy adult subjects (n = 27; 11 men, 16 women) and patients (n = 11; 4 men, 7 women) hospitalized for treatment of kleptomania with supermarket shoplifting were presented. Areas of interest (AOI) were established around the subject within the MKT+H and OUT+H images. Their gaze patterns on the images were measured by eye tracking and changes in oxy and deoxyhemoglobin as the subjects viewed the images. Images were simultaneously recorded in 10 regions within the prefrontal cortical area (PFC) using functional near-infrared spectroscopy.

Results:Bayesian ANOVA did not support an overall difference in any of the fixations for number, duration and length, number of blinks, and changes (expressed as coefficient of variation) in pupil diameters across gaze between patients and healthy subjects and between images. 🇧🇷 Bayesian t test or Mann-Whitney U test supported, albeit weakly, the alternative hypothesis over the null hypothesis in terms of duration (BF10 = 2.41, % error = 0.007) and spread (BF10 = 2.41) , % error = 0.009 ) of the fixations made, the AOI of the MKT+H image and those (BF10 = 4.51, error % = 0.001 in duration; BF10 = 1.927, error %=0.018 in dispersion) in OUT-H -Picture. The number of recording sites within the PFC where oxy- or deoxyhemoglobin responses increased from baseline (quantified as area under the curve, with significance defined as p < 0.05 using the t-test) over the of viewing images Significant increases or decreases were less in patients overall than in healthy subjects. Furthermore, principal component analysis with PFC oxyhemoglobin and deoxyhemoglobin changes revealed that correlations were strong across all images from healthy subjects (correlation coefficients ranging from 0.912 to 0.986), whereas in patients the correlations were weak to strong between images (correlation coefficients ranging from 0.865 to 0.987), except between the MKT-H and other images where they were significantly lower in the range of 0.272 to 0.643.

Conclusions:These results suggest that patients with kleptomania have different behavioral and neural responses to environmental stimuli associated with their uncontrolled behavior than healthy individuals.

Key words:Addiction, eye tracking, fNIRS, prefrontal cortex

To disclose:Nothing to disclose.

Robin Bonomi*, Mika Naganawa, Marcella Mignosa, Patrick Skosnik, Irina Esterlis, Nabeel Nabulsi, Marc Potenza, Richard Carson, Kelly Cosgrove, Robert Malison, Gustavo Angarita-Africano

Yale University, New Haven, Connecticut, USA. UU.

Background:A reduction in dendritic spine density in the brain's reward pathway (nucleus accumbens and prefrontal cortex) has been demonstrated in rodents following opiate withdrawal [1, 2]. It is unknown whether similar microarchitectural changes are present in people with opioid use disorder (OUD). Positron emission tomography (PET) with the radioligand 11C-UCB-J that selectively binds to synaptic vesicle protein 2A (SV2A) is a new method to visualize and quantify synaptic density in the living human brain [3, 4] . Recently, PET imaging studies with 11C-UCB-J have shown relatively decreased synaptic density in other substance use disorders [5, 6].

Methods:People with OUD, diagnosed according to DSM-5 criteria (N = 6, 36.7 +/-7.8 years, BMI: 28.3 +/- 7.1 kg/m2, all white men), were detoxified in the hospital and monitored for withdrawal prior to PET imaging with 11C-UCB-J. Demographically matched healthy controls (N = 6, 38.5 +/- 8.7 years, BMI: 25.0 +/- 3 kg/m2, all white males) also participated in an 11C-UCB-J PET scan participated to assess differences in SV2A density between the two populations. Female subjects also participated, but unfortunately it was not possible to obtain arterial blood data from these three subjects for various reasons. Volume of distribution (VT) calculated using a tissue compartment model with arterial input function with regions of interest analyzed and compared including the anterior cingulate (ACC), dorsomedial and ventromedial prefrontal cortex (PFC), medial orbitofrontal cortex and (OFC) was calculated), globus pallidus and striatum. Groups were compared using independent two-sample and two-tailed t-tests.

Results:Initial PET results showed significantly lower VT in regions of the striatum pallidus, including the globus pallidus (VT: N=6; -18%; p=0.03), putamen (VT: N=6; -12%; p = 0.035) and ventral striatum (VT: N = 6; -13%; p = 0.07) in OUD participants. In addition, a significant negative correlation was found between smoking (cigarettes/day) and globus pallidus VT values ​​(N = 6, slope = -0.1596, P = 0.01), other regions were tested, but not reported. significant. No significant correlation was found between opioid dose used and VT scores for this sample cohort.

Conclusions:These preliminary analyzes of 11C-UCB-J-PET indicate reduced synaptic density in the striatum and globus pallidus in people with OUD. To our knowledge, this represents the first in vivo clinical image showing differences in synaptic density in OUD compared to HC participants. While these preliminary results are consistent with preclinical work in the literature, there are several limitations such as B. Small samples, no women, and possible confounding effects for nicotine. Restrictions will be addressed with ongoing recruiting. Future analyzes should use partial volume corrections as well as a detailed comparison between groups for demographic data. If confirmed, these preliminary differences among OUD participants would support future studies of agents with synaptotropic effects [7-13].

References:

1. Robinson, TE and B. Kolb, Morphine alters the structure of neurons in the rat nucleus accumbens and neocortex. Synapse, 1999. 33(2): p. 160-2.

2. Robinson, T.E., et al., Generalized but region-specific effects of experimenter-administered versus self-administered morphine on the dendritic spines of the nucleus accumbens, hippocampus, and neocortex of adult rats. Synapse, 2002. 46(4): p. 271-9.

3. Finnema, S.J., et al., Imaging of Synaptic Density in the Living Human Brain. Sci Transl Med, 2016. 8(348): p. 348ra96.

4. Nabulsi, N.B., et al., Synthesis and preclinical evaluation of 11C-UCB-J as a PET marker for glycoprotein 2A imaging of synaptic vesicles in the brain. J Nucl Med, 2016. 57(5): p. 777-84.

5. Angarita, GA, et al., Inferior prefrontal cortical synaptic vesicle junction in cocaine use disorder: an exploratory study (11) of C-UCB-J positron emission tomography in humans. Addict Biol, 2022. 27(2): p. e13123.

6. D'Souza, D.C., et al., Preliminary in vivo evidence for decreased hippocampal synapse density in cannabis use disorder. Mol Psychiatry, 2021. 26(7): p. 3192-3200.

7. Kelly, J.R., et al., The Psychedelic Renaissance: Psychiatry's Next Ride? Go J Psychol Med, 2019: p. 1-5

8. Ly, C., et al., Psychedelics promote structural and functional neuronal plasticity. Cell Representative, 2018. 23(11): p. 3170-3182.

9. Olson, D.E., Psychoplastogens: A Promising Class of Neurotherapeutics That Promote Plasticity. J Exp Neurosci, 2018. 12: p. 1179069518800508.

10. Duman, C.H. and R. S. Duman, Spinal synapse remodeling in the pathophysiology and treatment of depression. Neurosci Lett, 2015. 601: p. 20-9.

11. de Vos, C.M.H., N.L. Mason and K.P.C. Kuypers, psychedelics and neuroplasticity: a systematic review revealing the biological basis of psychedelics. Frontal Psychiatry, 2021. 12: p. 724606.

12. Shao, L.X., et al., Psilocybin induces rapid and sustained growth of dendritic spines in the frontal cortex in vivo. Neuron, 2021. 109(16): p. 2535-2544.e4.

13. Raval, N.R., et al., A single dose of psilocybin increases synaptic density and decreases 5-HT(2A) receptor density in pig brain. international J. Mol. Sci., 2021. 22(2).

Key words:PET imaging, opioid use disorder, synaptic density, PET tracer, [11C]UCB-J

To disclose:Nothing to disclose.

Michael Van Ameringen*, Bárbara T. M. Q. dos Santos, Beth Patterson, Maryam Rahat, Juliette Mojgani, Grace Lethbridge, Fernando Sumiya, Carolina Goldman Bergmann

McMaster University, Hamilton, Canada

Background:Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder characterized by inattention, hyperactivity and impulsivity. According to the Replication of the National Comorbidity Survey, the 12-month prevalence rate of ADHD in adults is 4.4% [1]. ADHD often has adverse consequences in all areas of life, as well as increased comorbidity with other psychiatric disorders such as anxiety and mood disorders and substance abuse [2,3]. Although effective, first-line treatments for ADHD are associated with side effects that often result in poor adherence to therapy [4]. Marijuana is one of the most widely used psychoactive substances in the world; Global adult cannabis use in the last 12 months was estimated at 3.8%. Cannabis has been reported to help improve focus and hyperactivity in people with ADHD [5]. Among people with ADHD, the prevalence of cannabis use is higher than in the general population, with estimates of 34-46% among treatment-seeking patients who use cannabis [6]. While the relationship between ADHD and substance abuse is well known, the literature examining the effects of cannabis on ADHD symptoms is sparse and ambiguous. Few studies have examined the prevalence of cannabis use as a self-medication strategy in ADHD and the effects of cannabis on specific symptoms. This international cross-sectional study aimed to fill this gap by asking people with ADHD about the frequency and benefit of cannabis use in managing ADHD symptoms.

Methods:Adults (all genders) aged 18 years and older with a reported lifetime diagnosis of ADHD completed an online survey published between August 2020 and February 2022 in English. After signing an electronic informed consent form, a battery of questionnaires were completed, including the Barkley ADHD Rating Scale-IV for Adults (BAARS-IV), Quick Screen, Generalized Anxiety Disorder-7 (GAD-7) and the Patient Health Questionnaire. (PHQ-9), to assess the severity of depression. Demographic data and information about current and past substance use were also collected. Validated cutoff scores on the GAD-7 (≥15) and PHQ-9 (≥15) were used to estimate rates of moderate GAD and major depressive disorder (MDD). Statistical methods included descriptive statistics, chi-square for normally distributed variables, and Mann-Whitney analysis for non-normal distributions (only BAARS-IV was non-parametric).

Results:The survey was completed by 838. Respondents were primarily female (71%), Caucasian (79%) and educated (41% with a college degree); with a mean age of 31.8 ± 9.9; mainly from Canada (56.2%), United States (24.9%) and United Kingdom (4.4%). The majority (76%) were receiving pharmacological treatment for ADHD. The mean BAARS-IV score was 16 (range 5.00-20.00), indicating that most fell in the 98th to 99th percentile. Mean GAD-7 (12.03 ± 5.3) and PHQ-9 (14.65 ± 5.8) were above the clinical threshold for diagnosis; 28.5% met the threshold criteria for severe GAD, while 44.7% met the criteria for moderate MDD. Although lifetime rates of alcohol (89%) and tobacco (58.9%) use were similar to those in the general population, rates of cannabis use (77.3%), amphetamine/methamphetamine use ( 29%) and hallucinogen use (33.6%), nearly double the general North American population [7,8]. More than half of the sample (55.6%) claims to have consumed cannabis in the last 6 months. Within this group of current users (n = 466), 51.1% state that they use marijuana daily or almost daily. The majority (62.8%) of the total sample reported having used substances to treat their ADHD symptoms at some point in their lives. In this group (n = 526), ​​70% used marijuana to control ADHD and reported feeling calmer (74.5%), falling asleep more easily (70.1%) and feeling less irritable or aggressive (59.3%). 🇧🇷 Although 50.6% reported that marijuana did not make their ADHD symptoms worse, respondents also reported that marijuana made their ADHD symptoms worse Losing thought processes (45.1%) Having greater difficulty concentrating (31.9%) and greater difficulties in organizing tasks and activities (27.8%). The severity of ADHD symptoms was not associated with cannabis use or comorbid anxiety symptoms. However, those with moderate MDD had significantly higher BAARS-IV scores (p < 0.0001). People with moderate GAD and MDD were significantly more likely to report current cannabis use (p<0.01 – GAD; p<<=0.05 – MDD) as well as a significantly higher frequency of current cannabis use (p< 0.00001 for both). 🇧🇷

Conclusions:In this online sample of respondents with ADHD, lifetime rates of substance use (excluding alcohol and tobacco) were much higher than norms for the US population. This is particularly surprising given that a high proportion of the sample were women. Drug use tends to be higher in the male population. Although the majority of respondents reported using cannabis to treat their ADHD symptoms, the benefits are unclear as the symptoms that improved are not the main ADHD symptoms. It appears that individuals with anxiety and comorbid depressive symptoms use marijuana more than those without this comorbidity, raising the possibility that marijuana may benefit anxiety and depression symptoms in this group.

Key words:ADHD, cannabis use, anxiety, major depression

Disclosures: Allergan, Almatica, Bausch Health, Brainsway, Elvium, Empowerpharm, Jazz, Lundbeck, Otsuka, Tilray, Vistagen: Advisory Board (auto), Biohaven, Otsuka: Research Contract (auto), Canadian Institute for Health Research, Michael G DeGroote Center for Medicinal Cannabis Research, Elvium: Grant (author), UptoDate: Honorary (author), Abbvie, Allergan, Elvium, Lundbeck, Otsuka, Pfizer, Sunovion, Takeda: Speakers Bureau (author)

Sandra Sanchez-Roige, Mariela Jennings, Hayley Thorpe, Jazlene Mallari, Lieke van der Werf, Sevim Bianchi, Calvin Lee, Travis Mallard, Samuel Barnes, Jin Yi Wu, Amanda Barkley-Levenson, Ely Boussaty, Cedric Snethlage, Danielle Schafer, Zeljana Babic, Boyer W. Winters, Katherine Watters, Thomas Biederer, James MacKillop, David Stephens, Sarah L. Elson, Pierre Fontanillas, Jibran Khokhar, Jared Young, Abraham Palmer*

University of California San Diego, La Jolla, California, USA

Background:Impulsivity is a multidimensional inherited phenotype, usually related to the tendency to act prematurely and associated with various forms of psychopathology, including substance use disorders.

Methods:We conducted genomic-wide association studies (GWAS) of eight impulsive personality traits from the Barratt Impulsivity Scale and the short UPPS-P Impulsive Personality Scale (N = 123,509-133,517 23andMe survey participants of European descent) and a measure of drug experimentation (N=130,684). Since these GWAS implicated the CADM2 gene, we then performed a complete phenomenon study (PheWAS) of several of the variants implicated in CADM2 in a multi-ancestor cohort of 23andMe (N = 3,229,317, European; N = 579,623, Latin ; N = 199,663, African-American). Finally, we produced Cadm2 mutant mice and tested them with a series of analogous behavioral tasks.

Results:In humans, impulsive personality traits have shown modest chip heritability (∼6-11%) and moderate genetic correlations (rg = .20-.50) with other personality traits and various psychiatric and medical traits. We reproduced previous GWAS associations of these traits and found new associations including DRD2, CRHR1, FOXP2, TCF4, PTPRF. PheWAS variants for CADM2 identified associations with 378 traits in European participants and 47 traits in Latino participants, replicated associations with risk behaviors, cognition, and BMI, and revealed new associations such as allergies, anxiety, irritable bowel syndrome, and migraine. The Cadm2 mutant mice recapitulated some of the associations found in humans, including impulsivity, cognition and BMI.

Conclusions:Our results further describe the role of CADM2 in impulsivity and many other psychiatric and somatic traits among the ancestors, with additional support from studies in Cadm2 mutant mice.

Key words:GWAS, impulsivity, mouse genetics, polysubstance abuse

Disclosures: Vivid Genomics: Advisory Board (himself), Patent Holder: (himself)

Nathan Kolla*, Michelle De Pol, Dorsa Rafiei

University of Toronto, Toronto, Canada

Background:Borderline personality disorder (BPD) is a debilitating psychiatric disorder often associated with major depressive disorder (MDD). However, there is a lack of research examining biomarkers common to both diseases. The endocannabinoid system (ECS) is a powerful modulator of mood and stress circuits, and its dysregulation has been implicated in both animal and human models. Fatty acid amide hydrolase (FAAH), an ECS enzyme, plays a crucial role in the metabolism of endogenous cannabinoids. Preclinical evidence suggests that FAAH levels are elevated in the frontolimbic regions of the brain in MDD, and a previous positron emission tomography (PET) study found elevated FAAH in the prefrontal cortex of people with BPD. A variant of the FAAH gene (rs324420) also contributes to different levels of FAAH expression. However, ECS has never been characterized in people with comorbid BPD + MDD using in vivo imaging techniques. We hypothesized that cerebral FAAH would be increased in the prefrontal cortex, hippocampus and anterior cingulate cortex in people with BPD+MDD compared to healthy PET controls.

Methods:Ten patients with BPD + MDD aged between 18 and 65 years and 10 age-matched healthy controls were included in this pilot study. There were nine women in the comorbid group and eight women in the healthy group. Eligible psychiatric participants were taking no medications and met criteria for a current major depressive episode in addition to BPD. Control participants were excluded if they had a history of psychiatric disorders. All participants had a negative urine drug screen on study days. FAAH binding was measured by PET with the radiotracer [11C]CURB. Participants also underwent genotyping to determine the FAAH gene polymorphism. Mood and personality questionnaires were administered for exploratory correlation analysis. A linear mixed-effects model was used to determine differences in FAAH linkage between the two groups, where genotype was a fixed factor.

Results:No significant differences in brain levels of FAAH were observed between patients with BPD+MDD and controls in any brain region examined, including the prefrontal cortex, anterior cingulate cortex, and hippocampus. Whole brain analysis also found no differences in amygdala, temporal cortex, insula, thalamus, dorsal caudate, ventral striatum, and cerebellum between groups after Bonferroni correction. However, exploratory analyzes showed a significant positive correlation between FAAH binding in the ventrolateral prefrontal cortex (vlPFC) and impulsivity, as measured by the Barratt Impulsivity Scale-11 (BIS-11), within the BPD + MDD group. (r = 0.635, p = 0.048).

Conclusions:Given the lack of response to current therapies in patients with BPD and MDD, new biomarkers for these disorders need to be investigated. Our pilot study is the first to investigate FAAH in BPD + MDD comorbidity with [11C]CURB PET. No significant differences were observed between groups in terms of binding to FAAH. However, our sample is probably too weak at this point to see any effect. Our exploratory analyzes suggest that prefrontal FAAH may be related to impulsive behaviors in BPD + MDD, which is relevant since impulsivity is a core feature of BPD. Defective vlPFC function has been associated with impulsive decision-making, and it is possible that elevated FAAH in the vlPFC affects neurotransmission and leads to impulsivity. However, more research is needed to elucidate this possible mechanism.

Key words:Borderline personality disorder, major depression, endocannabinoid system, positron emission tomography (PET), fatty acid amide hydrolase, PET, cannabis

To disclose:Nothing to disclose.

Samantha Ayoub*, Avraham Libster, Stephanie Dulawa, Jared Young

University of California - San Diego, San Diego, California, USA

Background:Dopamine (DA) modulates risky decisions across species. Psychiatric disorders known to affect DA function (eg, schizophrenia, bipolar disorder) perform worse on risk decision tasks, for example. B. Iowa matching task during treatments with DA agonists, z. PPX), lead to game issues. Using a risk task, Zalocusky (2016) demonstrated that risk preference in male rats can be increased by systemic administration of PPX and decreased by optogenetic silencing of neurons expressing DA2R in the nucleus accumbens (NAc). However, gender differences have not been studied and the role of gender blocking or DA2R in risk decisions remains unclear. Here, we trained female and male rats on the same task to detect sex differences in risk preference at baseline and in response to pharmacological challenges of PPX, the DA2R antagonist sulpiride (SUL) and the dopamine transporter inhibitor (DAT). 🇧🇷 12909 (GBR).

Methods:In operant boxes, rats could choose between one of two nostrils, one providing 50 µL of strawberry milkshake (safe option) and the other a 10 µL treat with 75% probability or a chance of 170. µL with 25% probability. probability (risk option). 🇧🇷 Once trained to a stable baseline risk preference, rats were treated with PPX (0.15 or 0.3 mg/kg; Experiment 1) or SUL (30 mg/kg; Experiment 2) for 3 days, each separately by washing with saline solution. In Experiment 3, animals were challenged after an injection of GBR (5 or 16 mg/kg) or vehicle. The primary outcome variable was risk selection percentage (%CR).

Results:At baseline, women were less risk averse/averse than men. Experiment 1: Broken down between saline and drug trials, there was a significant drug effect on %CR change from baseline [F(1,18)=10.5, p<0.01], with PPX increasing % CR. When analyzed on each test day, a session main effect [F(6,108)=3.6, p<0.005] was observed, as well as a session*gender*drug interaction [F(6,108)=2.2, p <0.0.05] . Post hoc analysis revealed that women differed from men in response time to PPX, depending on the administered dose. Trial 2: Split between saline and drug trials, there was a significant drug effect on %HR change from baseline [F(1,6)=20.0, p<0.01], with SUL decreasing % CR. There was also a trend towards drug-gender interaction [F(1,6)=3.6, p=0.11] with more pronounced attenuation of %CR by SUL in females. A similar pattern was observed when data from all drug and saline tests were analyzed. Experiment 3: There was a significant effect of GBR on the %CR change from baseline [F(2,26)=4.0, p<0.05], with the high dose of GBR (16 mg/kg) %CR compared to VEH and GBR increased at low doses (5 mg/kg; p<0.05).

Conclusions:Together, these data indicate sex modulation in baseline risk preferences and that female rats may be more sensitive to DA manipulation in risky decisions, underscoring the need to track sex differences in such tasks. The data further support DAT inhibition (GBR) as restoration of mania-like risk preference in rodents. Ongoing studies will determine whether DA2R-NAc activity shows a similar gender-specific change in DA during risk preference. Understanding the neural basis of sex-based risk differences and the modulation of AD risk will improve management of psychiatric disorders that alter risk decisions, particularly in AD-prescribed drug populations.

Key words:Risky decision making, dopamine D2 receptor, sex differences

To disclose:Nothing to disclose.

Amanda Iglesias*, Sara Westbrook, Stephen Chang, Justin Chung, Paolo Campus, Shelly Flagel

University of Michigan, Ann Arbor, Michigan, USA. UU.

Background:The survival of an organism depends on its ability to respond appropriately to signals from the environment. Associative learning processes underlie an individual's response to such cues. For some, cues paired with rewards receive incentive motivational value (incentive salience) and can gain excessive control, resulting in maladaptive behavior characteristic of psychopathology. To study the neural mechanisms that promote incentive learning, we use the goal tracker (GT)/signal tracker (ST) animal model. In Pavlovian Conditioned Approach (PavCA) training, TGs attribute predictive value to reward cues; while TS attribute predictive and incentive value to such signals. Attributing a stimulating motivational value or stimulating emphasis converts the cue into an attractive and desirable stimulus. In STs, suggestions associated with food and drugs acquire an excessive incentive value and trigger maladaptive behavior. Therefore, the GT/ST model can be used to elucidate the neurobiological mechanisms that encode behaviors based on adaptive or maladaptive signals. GT and ST are based on distinct neurobiological mechanisms, and the paraventricular nucleus of the thalamus (PVT) has emerged as the neural center mediating their distinct differences in associative learning. Previous evidence has led us to postulate that upward projections to the PVT convey the incentive value of reward-associated cues, with the lateral hypothalamus (LH) sending dense orexinergic (OXergic) projections to the PVT acting as the tipping point. neural node. Orexin (OX) is known to play a role in motivation, and administration of OX receptor antagonists in DVT attenuates the incentive value of food-coupled signals in STs. We hypothesize that OXergic transmission in the LH-PVT pathway encodes the excitatory motivational value of reward cues and modulates the propensity to follow cues. Thus, we postulate that excitation of the signaling pathway via optogenetics would trigger trait tracking and inhibition of the post-learning signaling pathway via chemogenetics would reduce trait tracking behavior.

Methods:Here, we examine the role of the LH-PVT signaling pathway in encoding the value of reward signals through (1) optogenetic excitation and (2) chemogenetic inhibition during PavCA behavior. During PavCA sessions, a lighted cue (lever) is extended for 8 seconds and then retracted, and a food pellet is dispensed into a food cup. In the optogenetics study, we used male and female OX-Cre Long Evans transgenic mice (N = 11) expressing Cre recombinase in OX neurons and infused them with a retrograde Cre-dependent excitatory optogenetic virus (pAAVrg-Ef1α-DIO-ChR2-EYFP ; canalrhodopsin, ChR2) or empty vector (pAAVrg-Ef1α-DIO-EYFP; control) in anterior PVT. Animals received laser-induced excitation of LH-PVT neurons during cue (lever) presentation in sessions 1-5.

In the chemogenetic study, we used a two-vector approach to selectively express a DREADD inhibitor (Gi) virus in the LH-PVT pathway in inbred male Sprague-Dawley rats (N = 46). A retrograde Cre virus (pAAVrg-hSyn-EGFP-Cre) was infused into the anterior and posterior PVT, while a Cre-dependent Gi virus (pAAV8-hSyn-DIO-hM4D-mCherry) was infused bilaterally into the LH. After virus incubation, the mice received 7 sessions of PavCA. After acquiring a conditioned response, rats received vehicle or clozapine N-oxide (CNO; 5 mg/kg) prior to PavCA 5-7 sessions to activate Gi-DREADDs.

Results:In the optogenetics study, preliminary results suggest that stimulation of the LH-PVT OXergic signaling pathway during signal presentation leads to increased target tracking behavior in ChR2 mice (n=6) compared to controls (n=5 ). This effect appears to be more pronounced in male ChR2 mice (n = 3) compared to male EYFP (n = 2), female ChR2 (n = 3) and female EYFP (n = 3); However, studies are underway to increase the sample size.

In the chemogenetic study, we evaluated the impact of Gi-DREADD activation on the expression of a learned conditioned response, PavCA session 5-7. A mixed-effects linear model analysis compared the effect of treatment (VEH vs. CNO) and phenotype (ST vs. GT vs. IR (intermediate response)) for different behaviors in PavCA between sessions, and for all measures there was no a significant difference. phenotype effect (P < 0.005). When phenotypes were assessed independently by repeated measures ANOVA, there was no treatment effect at sessions 5-7 for ST (VEH, n = 3; NOC, n = 5) or IR (VEH, n = 7; NOC, n = 7) ). However, in TGs there was a significant treatment effect, such that TGs treated with CNO (n = 8) had less contact with the food cup (p = 0.034), less likely to approach the food cup (p = 0.002), and a slower approach to the food cup (p = 0.01) than VEH-treated TGs (n = 16).

Conclusions:These results suggest that the LH-PVT pathway plays an important role in goal-directed behavior. Preliminary results suggest that optogenetic stimulation of OXergic neurons in the LH-PVT pathway of male transgenic mice increases target-following behavior. Furthermore, chemogenetic inhibition of the LH-PVT signaling pathway in inbred male rats decreases the expression of GT selection behaviors without affecting ST or IR behaviors. Thus, the LH-PVT pathway appears to modulate predictive value encoding and expression of goal-directed behaviors both early in training and after acquisition of a conditioned response. Ongoing studies are increasing sample sizes in both studies to further investigate a possible role of the LH-PVT pathway in incentive learning and any gender differences that may arise.

Key words:Individual differences, lateral hypothalamus, paraventricular thalamic nucleus, excitatory prominence, Pavlovian conditioning

To disclose:Nothing to disclose.

Ka Ng, Arati Sharma, Mitchell Spring, Kate Nautiyal*

University of Dartmouth, Hanover, New Hampshire, EE. UU.

Background:Serotonin affects reward processing, threat recognition, behavior inhibition, and other components of motivation and behavior control that are commonly disrupted in a variety of psychiatric disorders. In the dorsal striatum (DS), pharmacological manipulation of serotonin signaling disrupts behavioral control and prospective reward encoding. In addition, many serotonin receptors, including the serotonin 1B receptor (5-HT1BR), are involved in the regulation of impulsive and reward-motivated behavior. However, the nature of how serotonin behaviorally encodes/controls reward-related behavior is not well understood, nor have the circuit-level mechanisms by which serotonin modulates reward-related behavior in the striatum been identified.

Methods:We used miniature microendoscopes to calculate dorsal striatum medium spiny neurons (MSNs) in adult mice during a simple appetizing operant task in the DIY-NAMIC system to analyze reward-related neural dynamics (n = 5; 3 males, 2 females). In addition, mice lacking 5-HT1BR were also photographed to assess the effect of 5-HT1BR signaling on reward-related MSN activity. In parallel, we used a fluorescent sensor based on G protein-coupled receptor activation for serotonin (GRAB-5-HT) to measure serotonin release in the dorsal striatum of mice during reward tests administered with the Davis lickometer (n = 10; 6 male, 4 female). These methods allow measurement of neural dynamics and serotonin signaling on a timescale compatible with reward-related behaviors on individual trials in the Pavlovian and operant paradigms.

Results:We analyzed changes in MSN D1 and D2 calcium event rates during different phases of reward-seeking behavior and in response to increased palatable reward. We found that most cells dim their reward prediction and reward delivery signals. Using supervised learning algorithms, we were able to accurately classify correct, incorrect, and ignored behavior attempts based on the neural data generated during testing. The calculated accuracy was >99% and dropped to <40% when training labels were moved. We also used recursive function exclusion to determine the number and pattern of cells that contributed the most to the classifier's performance. Overall, our modeling work shows that MSN activity in the dorsal striatum uses a relatively small number of cells for overall encoding of the induced reward. The serotonin level measured by the GRAB-5-HT sensor in the DS increased before receiving the reward. Interestingly, the increase in serotonin signaling preceded reward consumption and was closely related to initiation of reward approach following reward availability signaling. The majority of reward licks (96%) occurred within 2 seconds of the onset of the identified significant serotonin increase. Additional studies varying reward concentration with 2- and 6-vial paradigms are ongoing, but preliminary data suggest that there is some increase in the magnitude and duration of serotonin increases with increases in reward value. Additional studies using GRAB-5-HT imaging are focused on examining the role of serotonin in encoding expected reward value, anticipation and motivation.

Conclusions:Our results are important to understand the encoding of reward value in DS and its modulation by serotonin. Current analysis of calcium imaging data aims to identify the effect of 5-HT1B on MSN reward-related neuronal activity and to determine how classifiers might change in the absence of this serotonin signaling. Characterizing real-time serotonin release and its influence on MSN neural activity and reward-related behaviors is important for understanding how serotonin modulates reward processing and behavior control.

Key words:Serotonin, Reward, GRAB-5HT, dorsal striatum

To disclose:Nothing to disclose.

Anton Schulmann*, Nirmala Akula, Stefano Marenco, Pavan Auluck, Armin Raznahan, Siyuan Liu, Alexandra DeCasien, Qing Xu, Ningping Feng, Bhaskar Kolachana, Barbara Lipska, Xueying (Sherry) Jiang, Asya Khlebodorova, Justin Lack, Francis McMahon

NIMH, Bethesda, Maryland, United States

Background:Copy number variants (CNVs) are structural variants in which a large stretch of genomic DNA, usually tens of kilobases, is duplicated or deleted. Several CNVs have been associated with increased risk of neuropsychiatric disorders, including major depressive disorder, bipolar disorder, schizophrenia and autism. Although these CNVs are relatively rare, they are highly pervasive and pleiotropic, but their impact on gene expression in the brain has been poorly studied. Here we evaluated changes in gene expression in the postmortem brain of neuropsychiatric CNV carriers compared to matched controls.

Methods:We identified 13 verified carriers of neuropsychiatric CNVs aged 10 years or older from SNP genotyping matrix data in three postmortem brain repositories. Samples included CNVs mirrored at 22q11.2, 16p11.2, 1q21.1, 15q11.2 (BP1-BP2) and the Williams-Beuren syndrome deletion 7q11.23. Where available, two brain regions, the dorsolateral prefrontal cortex and the anterior cingulate cortex, were profiled from a vehicle and two matched controls, resulting in a total sample size of 62. RNA sequencing data were quantified at the gene level and analyzed using linear mixed models to explain the nested experimental design. Multivariate adaptive contraction was used to assess convergent effects across multiple CNVs.

Results:Although only a few genes exceeded the 5% false detection rate, most genes within the respective CNV regions were underexpressed in de