Brain serotonin, oxytocin, and their interaction: Relevance for eating disorders.

Introduction: Eating disorders are characterized by maladaptive eating behaviors and preoccupations around body shape, weight, and eating. The serotonin system has been among the most widely studied neurobiological factors in relation to eating disorders. Recent research also highlighted the role of oxytocin.

Hippocampal Lesions in Male Rats Produce Retrograde Memory Loss for Over-Trained Spatial Memory but Do Not Impact Appetitive-Contextual Memory: Implications for Theories of Memory Organization in the Mammalian Brain.

Evidence suggests that hippocampal (HPC) disruption following learning produces retrograde amnesia on a range of tasks. Many of these tasks do not require HPC function in the anterograde direction suggesting that, in the intact brain, the HPC is actively involved during all forms of learning. However, prior work has also demonstrated double dissociations of HPC and amygdala function, which is inconsistent with this view.

Mesolimbic dopamine neurons drive infradian rhythms in sleep-wake and heightened activity state.

Infradian mood and sleep-wake rhythms with periods of 48 hours and beyond have been observed in patients with bipolar disorder (BD), which even persist in the absence of exogenous timing cues, indicating an endogenous origin. Here, we show that mice exposed to methamphetamine in drinking water develop infradian locomotor rhythms with periods of 48 hours and beyond which extend to sleep length and manic state-associated behaviors in support of a model for cycling in BD. The cycling capacity is abrogated upon genetic disruption of dopamine (DA) production in DA neurons of the ventral tegmental area (VTA) or ablation of nucleus accumbens projecting DA neurons.

Considering the interconnected nature of social identities in neuroimaging research.

Considerable heterogeneity exists in the expression of complex human behaviors across the cognitive, personality and mental health domains. It is increasingly evident that individual variability in behavioral expression is substantially affected by sociodemographic factors that often interact with life experiences. Here, we formally address the urgent need to incorporate intersectional identities in neuroimaging studies of behavior, with a focus on research in mental health.

Developing standards for the implementation of stepped care in child and youth mental health service settings: protocol for a multi-method, delphi-based study.

Introduction: Canadian youth mental health (YMH) systems have the potential to urgently tackle the mental health treatment gap currently impacting young people, and stepped care (SC) is one model that can address this need. The adoption of SC models can guide the development of better-connected YMH systems by simplifying transitions and care pathways. To do so requires robust standards that are co-created across stakeholder groups, including with lived experience experts, to ensure the effective implementation of SC models.

Safety outcomes of ketamine for treatment-resistant depression in clinical settings and development of the ketamine side effect tool-revised (KSET-R).

Background: Ketamine and its derivates (e.g. esketamine) are increasingly used in clinical settings for treatment-resistant depression (TRD).

Longitudinal analysis of lifetime stressors and depression: Exploring intersectionality and tailoring social support for better mental health in a community population cohort.

Aims: Health inequalities studies need to understand how individuals simultaneously defined by several socioeconomic factors differ from others when facing a series of stressors across the lifespan in the risk of major depression (MD). Theoretical efforts, as well as empirical studies, have suggested a pertinent role of social support in mental health outcomes. However, little is known about which forms of social support would alleviate the negative impact of MD vulnerability in self-rated mental health (SRMH) across different socioeconomic groups.

Royal Canadian Mounted Police cadets' exposure to potentially psychologically traumatic events during the Cadet Training Program.

Lifetime exposures to potentially psychologically traumatic events (PPTEs) among Royal Canadian Mounted Police (RCMP) cadets starting the Cadet Training Program (CTP) appear lower than exposures reported by serving RCMP, but the prevalence of PPTE exposures during the CTP remains unknown. The current study assessed PPTE exposures during the CTP and examined associations with mental disorders among RCMP cadets. Participants were cadets (n = 449, 24.

Advancing digital sensing in mental health research.

Digital sensing tools, like smartphones and wearables, offer transformative potential for mental health research by enabling scalable, longitudinal data collection. Realizing this promise requires overcoming significant challenges including limited data standards, underpowered studies, and a disconnect between research aims and community needs. This report, based on the 2023 Workshop on Advancing Digital Sensing Tools for Mental Health, articulates strategies to address these challenges to ensure rigorous, equitable, and impactful research.

Exploring PDE5A upregulation in bipolar disorder: insights from single-nucleus RNA sequencing of human basal ganglia.

Basal ganglia is proposed to mediate symptoms underlying bipolar disorder (BD). To understand the cell type-specific gene expression and network changes of BD basal ganglia, we performed single-nucleus RNA sequencing of 30,752 nuclei from caudate, putamen, globus pallidus, and substantia nigra of control human postmortem brain and 24,672 nuclei from BD brain. Differential expression analysis revealed major difference lying in caudate, with BD medium spiny neurons (MSNs) expressing significantly higher PDE5A, a cGMP-specific phosphodiesterase.

Neonatal estradiol and early adversity interact to modify basolateral amygdala morphology and adult behavior in female rats.

Being raised under adverse conditions during infancy and childhood represents a significant risk factor for developing later psychopathologies and dysfunctions in emotional, affective, and cognitive abilities. Depending on the type, timing, and duration of early adversity, different consequences emerge across the sexes in both human and animal models, although our understanding of the underlying interactions between sex and early life stress (ELS) is still incomplete. In this study, we used the limited bedding (LB) paradigm, a well-described model of ELS in rat pups during the first 10 days of life, and tested whether masculinization of the female brain by neonatal injections of estradiol benzoate (EB) would recapitulate the ELS-induced vulnerability phenotype of males on morphology of the basolateral amygdala (BLA) principal neurons and pre-adolescent and adult behavior.

Altered m6A RNA methylation profiles in depression implicate the dysregulation of discrete cellular functions in males and females.

Adverse environmental stress represents a significant risk factor for major depressive disorder (MDD), often resulting in disrupted synaptic connectivity which is known to be partly regulated by epigenetic mechanisms. N-methyladenosine (m6A), an epitranscriptomic modification, has emerged as a crucial regulator of activity-dependent gene regulation. In this study, we characterized m6A profiles in the ventromedial prefrontal cortex (vmPFC) of individuals with MDD.

The role of psychotropics on the associations between extreme temperature and heat-related outcomes among people with mental health conditions: population-based study.

Background: The association between heatwave and heat-related outcomes in people with mental health conditions with and without psychotropics was unclear.

Methods: We identified people with severe mental illness (SMI) and depression, respectively, using Japanese claim data of Ibaraki prefecture during 1/1/2014-31/12/2021. We conducted self-controlled case series to estimate the incidence rate ratio (IRR) of heat-related illness, myocardial infarction and delirium, respectively, during 5-day pre-heatwave, heatwave, and 5-day post-heatwave periods all other periods (baseline) within an individual, stratified by periods prescribed psychotropics and periods not prescribed psychotropics, respectively.

Impact of a national dementia research consortium: The Canadian Consortium on Neurodegeneration in Aging (CCNA).

The Canadian Consortium on Neurodegeneration in Aging (CCNA) was created by the Canadian federal government through its health research funding agency, the Canadian Institutes for Health Research (CIHR), in 2014, as a response to the G7 initiative to fight dementia. Two five-year funding cycles (2014-2019; 2019-2024) have occurred following peer review, and a third cycle (Phase 3) has just begun. A unique construct was mandated, consisting of 20 national teams in Phase I and 19 teams in Phase II (with research topics spanning from basic to clinical science to health resource systems) along with cross-cutting programs to support them.

Older is order: entropy reduction in cortical spontaneous activity marks healthy aging.

Background: Entropy trajectories remain unclear for the aging process of human brain system due to the lacking of longitudinal neuroimaging resource.

Results: We used open data from an accelerated longitudinal cohort (PREVENT-AD) that included 24 healthy aging participants followed by 4 years with 5 visits per participant to establish cortical entropy aging curves and distinguish with the effects of age and cohort. This reveals that global cortical entropy decreased with aging, while a significant cohort effect was detectable that people who were born earlier showed higher cortical entropy.

Childhood sexual abuse and lifetime depressive symptoms: the importance of type and timing of childhood emotional maltreatment.

Background: Childhood sexual abuse (CSA) and emotional maltreatment are salient risk factors for the development of major depressive disorder (MDD) in women. However, the type- and timing-specific effects of emotional maltreatment experienced during adolescence on future depressive symptomatology in women with CSA have not been explored. The goal of this study was to fill this gap.

Differential effects of prolonged post-fixation on immunohistochemical and histochemical staining for postmortem human brains.

Purpose: Immunohistochemical (IHC) and histochemical (HC) staining techniques are widely used on human brains that are post-fixed in formalin and stored in brain banks worldwide for varying durations, from months to decades. Understanding the effects of prolonged post-fixation, postmortem interval (PMI), and age on these staining procedures is important for accurately interpreting their outcomes, thereby improving the diagnosis and research of brain disorders afflicting millions of people worldwide.

Methods: In this study, we conducted both IHC and HC staining on the prefrontal cortex of postmortem human brains post-fixed for 1, 5, 10, 15, and 20 years.