The effects of allostatic load on neural systems subserving motivation, mood regulation, and social affiliation

Allostatic interoceptive overload across psychiatric and neurological conditions

Emerging theories emphasize the crucial role of allostasis (anticipatory and adaptive regulation of the body's biological processes) and interoception (integration, anticipation, and regulation of internal bodily states) in adjusting physiological responses to environmental and bodily demands. This review explores the disruptions in integrated allostatic interoceptive mechanisms in psychiatric and neurological disorders, including anxiety, depression, Alzheimer's disease, and frontotemporal dementia. We assess the biological mechanisms associated with allostatic interoception, including whole-body cascades, brain structure and function of the allostatic interoceptive network, heart-brain interactions, respiratory-brain interactions, the gut-brain-microbiota axis, peripheral biological processes (inflammatory, immune), and epigenetic pathways. These processes span psychiatric and neurological conditions and call for developing dimensional and trans-nosological frameworks. We synthesize new pathways to understand how allostatic interoceptive processes modulate interactions between environmental demands and biological functions in brain disorders. We discuss current limitations of the framework and future transdisciplinary developments. This review opens a new research agenda for understanding how allostatic interoception involves brain predictive coding in psychiatry and neurology, allowing for better clinical application and the development of new therapeutic interventions.

RSA instability in mothers of preschoolers and adolescents is related to observations of supportive parenting behaviors

Respiratory sinus arrhythmia (RSA; a measure of respiratory modulation of vagal control of heart rate) is a dynamic process. For mothers, RSA functioning has been associated with depressive symptoms and coincides with supportive parenting. However, research has largely focused on RSA suppression (i.e., difference score from rest to stress task). The present study examined depressive symptoms and supportive parenting with RSA instability-a dynamic measure of the magnitude of RSA change across a task. In two samples of mothers (N = 210), one with preschoolers (Study 1: n = 108, Mage = 30.68 years, SD = 6.06, 47.0% Black, 43.0% White) and one with adolescents (Study 2: n = 102, Mage = 35.51, SD = 6.51, 75.2% Black), RSA instability was calculated during an interaction task. In both studies, instrumental supportive parenting behaviors were negatively related to RSA instability. Findings provide preliminary support for RSA instability as an indicator of physiological dysregulation for mothers.

Coping Responses in the Context of Family Stress Moderate the Association Between Childhood Anxiety and Adolescent Depressive Symptoms

Anxiety and depressive symptoms are common and highly interrelated. A relatively consistent temporal pattern of anxious and depressive symptoms has emerged from previous studies, such that the development of anxiety tends to precede and predict the development of depression rather than the other way around. Whether high levels of childhood anxiety predict depressive symptoms in late adolescence may depend, in part, on the ways in which children cope with stressful events. Accordingly, the present study used latent intercept models to examine involuntary and voluntary coping responses to familial stress as potential moderators of the association between childhood anxiety and adolescent depressive symptoms. Two hundred twenty-seven participants completed questionnaires measuring demographic variables as well as anxiety, depressive symptoms, and coping responses at a minimum of one time point over four waves of data collection (T1 Mage = 10.26 years, T2 Mage = 15.77 years, T3 Mage = 16.75 years, T4 Mage = 17.68 years). We found that childhood anxiety was positively associated with adolescent depressive symptoms when children reported higher levels of involuntary responses to family stress (e.g., rumination or physiological arousal) in conjunction with either lower levels of voluntary engaged responses (e.g., problem solving or emotion regulation) or higher levels of voluntary disengaged responses (e.g., avoidance or denial). These results shed light on the conditions under which childhood anxiety is associated with adolescent depressive symptoms and underscore the need for continued longitudinal and developmental research on this topic.

Perineuronal net structure as a non-cellular mechanism contributing to affective state: A scoping review

Affective state encompasses emotional responses to our physiology and influences how we perceive and respond within our environment. In affective disorders such as depression, cognitive adaptability is challenged, and structural and functional brain changes have been identified. However, an incomplete understanding persists of the molecular and cellular mechanisms at play in affective state. An exciting area of newly appreciated importance is perineuronal nets (PNNs); a specialised component of extracellular matrix playing a critical role in neuroprotection and synaptic plasticity. A scoping review found 24 studies demonstrating that PNNs are still a developing field of research with a promising general trend for stress in adulthood to increase the intensity of PNNs, whereas stress in adolescence reduced (potentially developmentally delayed) PNN numbers and intensity, while antidepressants correlated with reduced PNN numbers. Despite promising trends, limited research underscores the need for further exploration, emphasizing behavioral outcomes for validating affective states. Understanding PNNs' role may offer therapeutic insights for depression and inform biomarker development, advancing precision medicine and enhancing well-being.

Non-suicidal Self-injurious Thoughts and Behaviors Among Adolescent Inpatients

Non-suicidal self-injury (NSSI) is a serious public health concern that typically onsets during early adolescence. Adolescents (N = 980, ages 12-19 years) admitted for acute, residential psychiatric treatment completed baseline clinical interviews assessing mental disorders and questionnaires measuring demographics, early life adversity, and symptom severity. Prevalence rates of NSSI for lifetime (thoughts: 78%; behaviors: 72%), past year (thoughts: 74%; behaviors: 65%), and past month (thoughts: 68%; behaviors: 51%) were high. Although effect sizes were modest, the presence of a lifetime depressive disorder, sexual abuse, and comorbidity (i.e., three or more current disorders) were significant correlates of experiencing NSSI thoughts and behaviors. Furthermore, lifetime depressive disorder, current anxiety disorder, and comorbidity were associated with a greater odds of persistent NSSI thoughts and/or behaviors. Longitudinal studies are needed to determine whether targeting these factors reduces the persistence of NSSI thoughts and behaviors.

Injury, illness, and emotion: A review of the motivational continuum from trauma through recovery from an ecological perspective

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Investigating suicide related behaviours across sexual orientation and neighbourhood deprivation levels: A cohort study using linked health administrative data

BACKGROUND

There have been no studies examining how neighbourhood deprivation modifies the effects of sexual minority status on suicide-related behaviours (SRB). Sexual minority individuals in deprived areas may face unique challenges and stressors that exacerbate their risk of SRB. This study aims to investigate the association between sexual minority status and clinical SRB, and examine whether the effect of neighbourhood deprivation differs across sexual orientation.

METHODS

A population-representative survey sample (169,090 respondents weighted to represent 8,778,120 individuals; overall participation rate 75%) was linked to administrative health data in Ontario, Canada to measure SRB-related events (emergency department visits, hospitalizations, and deaths) from 2007 to 2017. Neighbourhood-level deprivation was measured using the Ontario Marginalisation index measure of material deprivation at the dissemination area level. Discrete-time survival analysis models, stratified by sex, tested the effects of neighbourhood deprivation and sexual minority status, while controlling for individual-level covariates.

RESULTS

Sexual minority men had 2.79 times higher odds of SRB compared to their heterosexual counterparts (95% CI 1.66 to 4.71), while sexual minority women had 2.14 times higher odds (95% CI 1.54 to 2.98). Additionally, neighbourhood deprivation was associated with higher odds of SRB: men in the most deprived neighbourhoods (Q5) had 2.01 times higher odds (95% CI 1.38 to 2.92) of SRB compared to those in the least deprived (Q1), while women had 1.75 times higher odds (95% CI 1.28 to 2.40). No significant interactions were observed between sexual minority status and neighbourhood deprivation levels.

CONCLUSION

In both men and women, sexual minority status and neighbourhood deprivation are independent risk factors for SRB. Despite the lack of effect modification, sexual minorities living in the most deprived neighbourhoods have the highest chances of SRB. Future investigations should evaluate interventions and policies to improve sexual minority mental health and address neighbourhood deprivation.

Reward sensitivity modulates the brain reward pathway in stress resilience via the inherent neuroendocrine system

In the previous 10 years, researchers have suggested a critical role for the brain reward system in stress resilience. However, no study has provided an empirical link between activity in the mesostriatal reward regions during stress and the recovery of cortisol stress response. Moreover, although reward sensitivity as a trait has been demonstrated to promote stress resilience, it remains unclear whether it modulates the brain reward system in stress resilience and how this effect is achieved by the inherent neuroendocrine system. To investigate these uncertainties, 70 young adults were recruited to participate in a ScanSTRESS task, and their brain imaging data and saliva samples (for cortisol assay) were collected during the task. In addition, we assessed reward sensitivity, cortisol awakening response, and intrinsic functional connectivity of the brain in all the participants. We found that left putamen activation during stress exposure positively predicted cortisol recovery. In addition, reward sensitivity was positively linked with activation of the left putamen, and this relationship was serially mediated by the cortisol awakening response and right hippocampus-left inferior frontal gyrus intrinsic connectivity. These findings suggest that reward sensitivity modulates reward pathways in stress resilience through the interplay of the diurnal stress response system and network of the hippocampus-prefrontal circuitry. Summarily, the current study built a model to highlight the dynamic and multifaceted interaction between pertinent allostatic factors in the reward-resilience pathway and uncovered new insight into the resilience function of the mesostriatal reward system during stress.

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Cortisol recovery can be predicted by activation of the left putamen in stress.

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Activation of the left putamen was positively linked with reward sensitivity.

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This relationship was serially mediated by the cortisol awakening response and right hippocampus-left inferior frontal gyrus intrinsic coupling.

Stress-related hippocampus activation mediates the association between polyvictimization and trait anxiety in adolescents

Early life stress exposures are associated with adverse health outcomes and heightened anxiety symptoms in adolescents. Stress-sensitive brain regions like the hippocampus and amygdala are particularly impacted by early life adversities and are also implicated in the development of anxiety disorders. However, to date, no studies have specifically examined the neural correlates of polyvictimization (exposure to multiple categories of victimization) or the contribution of stress-sensitive neural nodes to polyvictimization's impact on mental health. To elucidate these relationships, the current study analyzed associations between polyvictimization, hippocampal and amygdalar activation during an acute stress task and trait anxiety in a sample of 80 children and adolescents aged 9-16 years (33 female participants). Results showed that polyvictimization was associated with higher trait anxiety as well as greater stress-related right hippocampus activation, and this greater hippocampal activity predicted heightened trait anxiety. Robust mediation analyses revealed that stress-related right hippocampus activation partially mediated the relationship between polyvictimization and trait anxiety. Our results expand upon the existing polyvictimization literature by suggesting a possible neurobiological pathway through which polyvictimization is connected to the etiology of mental illness.

Long-Lasting Efficacy of Radio Electric Asymmetric Conveyer Neuromodulation Treatment on Functional Dysmetria, an Adaptive Motor Behavior

Background

Fluctuating asymmetry (FA) is widely defined as the deviation from perfect bilateral symmetry and is considered an epigenetic measure of environmental stress. Rinaldi and Fontani hypothesized that the FA morpho-functional changes originate from an adaptive motor behavior determined by functional alterations in the cerebellum and neural circuits, not caused by a lesion, but induced by environmental stress. They called this phenomenon functional dysmetria (FD). On this premise, they developed the radio electric asymmetric conveyer (REAC) technology, a neuromodulation technology aimed at optimizing the best neuro-psycho-motor strategies in relation to environmental interaction.

Aims

Previous studies showed that specific REAC neuro postural optimization (NPO) treatment can induce stable FD recovery. This study aimed to verify the duration of the NPO effect in inducing the stable FD recovery over time.

Materials and methods

Data were retrospectively collected from a population of 29,794 subjects who underwent a specific semiological FD assessment and received the NPO treatment, regardless of the pathology referred.

Results

The analysis of the data collected by the various participants in the study led us to ascertain the disappearance of FD in 100% of the cases treated, with a stability of the result detected up to 18 years after the single administration of the REAC NPO treatment.

Conclusions

The REAC NPO neurobiological modulation treatment consisting of a single administration surprisingly maintains a very long efficacy in the correction of FD. This effect can be explained as the long-lasting capacity of the NPO treatment to induce greater functional efficiency of the brain dynamics as proven in previous studies.

School Discipline as a Consequence of Violent Victimization in Adolescence: Understanding the Mediating Roles of Head Injury and Behavior

Pathways from violence to head injury and poor long-term outcomes have been found among numerous populations, however, have not yet been widely examined with youth exposed to violence. Traumatic brain injuries (TBIs) are linked to a range of consequences salient to adolescent development and well-being, such as impulsivity, academic abilities, and emotional processing. This gap in research has led to a missed opportunity to understand the consequences of youth victimization, particularly within the academic setting. The current study examined whether head injury and problem behaviors mediate the relationships between victimization and suspension/expulsion using data from the Pathways to Desistance Study, a multi-site, longitudinal study of serious adolescent offenders age 14-18. A sample of male youth who had witnessed violence (n = 1,094) reported a total score of victimization, number of early behavior problems (i.e., cheating, fighting, etc.), ever having a head injury (32.9%), and number of times suspended (adjusted M = 13.13; SD = 19.31) or expelled (adjusted M = 0.65; SD = 0.99). Structural equation modeling was used to examine direct and indirect pathways from victimization to suspension and expulsion through head injury and behavior. Direct pathways from victimization to school discipline were significant; indirect pathways mediated by only head injury were not significant, but indirect pathways through only problem behavior and through TBI and problem behavior were significant for both expulsion and suspension. Results suggest that youth who have been victimized are at higher risk for both suspension and expulsion and that this risk may be, in part, explained through increased head injury and problem behaviors. TBI screenings/services for violence-exposed youth and trauma-informed school-based services may help to deter trajectories toward suspension and expulsion but should be developed with attention to the influence of racial bias on pathways to school discipline.

The association between familial death in childhood or adolescence and subsequent substance use disorder: A systematic review and meta-analysis

BACKGROUND

Exposure to childhood adversity has been linked to long-term negative mental health consequences in adulthood.

PURPOSE

This review examined the association between exposure to the death of a family member (i.e., parent or sibling) during childhood or adolescence and the subsequent diagnosis of a substance use disorder.

METHODS

Electronic databases (Scopus, Medline (for Ovid), EMBASE, and PsychINFO) were searched for cohort and case-control studies in the English language. Studies were retained if it was demonstrable that exposure to death occurred before age 18, and that disorder was diagnosed subsequently. Sensitivity analyses were performed for the meta-analysis, and study quality assessed using the Newcastle-Ottawa Scale.

RESULTS

Nine studies, seven cohort and two case-control, were retained. Due to differential metrics (hazard ratios [HRs] versus odds/risk ratios [ORs/RRs]), only one meta-analysis was possible. Individuals experiencing familial death had 1.42 (95% CI = 0.96, 2.09) times the odds of developing a substance use disorder compared to those non-exposed. Where there was a statistically significant effect in other studies, these were mostly studies using National Registers (1.4 ≤ HR ≤ 2.51).

LIMITATIONS

Meta-analysis options were limited by the variety of study designs.

CONCLUSIONS

Evidence for a significant association between familial death and subsequent disorder appears to be an artefact of the study design. Implications of key findings. Further studies are required to better understand and estimate the association between familial death and substance use disorders. Registration and funding. The review was pre-registered (PROSPERO Reg No: CRD42020192892) and funded by the Irish Research Council (COALESCE/2019/61).

Partially Hydrolyzed Guar Gum Modulates Gut Microbiota, Regulates the Levels of Neurotransmitters, and Prevents CUMS-Induced Depressive-Like Behavior in Mice

SCOPE

Depression is the leading cause of disability around the world; however, most antidepressants have drug tolerance and serious side effects. In this study, it is explored whether partially hydrolyzed guar gum (PHGG) is a safe food that exhibits protection in a mouse model of depression.

METHODS AND RESULTS

PHGG is orally administered to mice with depression induced by chronic unpredictable mild stress (CUMS) in two animal experiments (prevention trial and intervention trial) to characterize the potentially protective effect of PHGG. The results in the prevention trial show that PHGG significantly inhibits the loss of body weight, and prevents CUMS-induced depressive-like behavior in mice. The beneficial effects may be associated with PHGG modulating the gut microbiota structure and then increasing the levels of short-chain fatty acids in mice feces and the levels of 5-hydroxytryptamine and dopamine in serum, striatum, and hippocampus. Besides, PHGG in the intervention trial is less effective than that in the prevention trial, but it may have a synergistic effect on improving depression with fluoxetine.

CONCLUSIONS

This study suggests that moderate daily intake of PHGG can contribute to relieving depressive-like behavior.

Individual differences in parent and child average RSA and parent psychological distress influence parent-child RSA synchrony

Parent-child synchrony of respiratory sinus arrhythmia (RSA) varies by risk, but novel approaches are needed to capture individual contributions to synchrony. Multilevel state-trait modeling was applied to examine how parental psychological distress and parent and child average RSA during challenge (reflecting individual regulatory capacities) shaped RSA synchrony in mother-child (n = 71) and father-child (n = 47) interactions. RSA synchrony was curvilinear such that greater in-the-moment RSA reactivity in one partner prompted greater reactivity in the other. Higher risk (lower average RSA; higher distress) predicted in-the-moment RSA withdrawal to partner RSA changes, whereas lower risk (higher average RSA; lower distress) predicted in-the-moment RSA augmentation. In some models, one's higher average RSA prompted the partner's greater reactivity and thus synchrony when parental distress was higher. However, the presence and direction of synchrony was not consistently adaptive nor maladaptive across models, suggesting its meaning relies on theory and the parent and risk factors in question.

Neuroimaging Markers of Resiliency in Youth at Clinical High Risk for Psychosis: A Qualitative Review

Psychotic disorders are highly debilitating and constitute a major public health burden. Identifying markers of psychosis risk and resilience is a necessary step toward understanding etiology and informing prevention and treatment efforts in individuals at clinical high risk (CHR) for psychosis. In this context, it is important to consider that neural risk markers have been particularly useful in identifying mechanistic determinants along with predicting clinical outcomes. Notably, despite a growing body of supportive literature and the promise of recent findings identifying potential neural markers, the current work on CHR resilience markers has received little attention. The present review provides a brief overview of brain-based risk markers with a focus on predicting symptom course. Next, the review turns to protective markers, examining research from nonpsychiatric and schizophrenia fields to build an understanding of framing, priorities, and potential, applying these ideas to contextualizing a small but informative body of resiliency-relevant CHR research. Four domains (neurocognition, emotion regulation, allostatic load, and sensory and sensorimotor function) were identified and are discussed in terms of behavioral and neural markers. Taken together, the literature suggests significant predictive value for brain-based markers for individuals at CHR for psychosis, and the limited but compelling resiliency work highlights the critical importance of expanding this promising area of inquiry.

Parsing inter- and intra-individual variability in key nervous system mechanisms of stress responsivity and across functional domains

Exposure to stressful events is omnipresent in modern human life, yet people show considerable heterogeneity in the impact of stress exposure(s) on their functionality and overall health. Encounter with stressor(s) is counteracted by an intricate repertoire of nervous-system responses. This narrative review starts with a brief summary of the vast evidence that supports heart rate variability, cortisol secretion, and large-scale cortical network interactions as kay physiological, endocrinological, and neural mechanisms of stress responsivity, respectively. The second section highlights potential sources for inter-individual variability in these mechanisms, by focusing on biological, environmental, social, habitual, and psychological factors that may influence stress responsivity patterns and thus contribute to heterogeneity in the impact of stress exposure on functionality and health. The third section introduces intra-individually variability in stress responsivity across functional domains as a novel putative source for heterogeneity in the impact of stress exposure. Challenges and future directions are further discussed. Parsing inter- and intra-individual variability in nervous-system mechanisms of stress responsivity and across functional domains is critical towards potential clinical translation.

Psychological mechanisms and functions of 5-HT and SSRIs in potential therapeutic change: Lessons from the serotonergic modulation of action selection, learning, affect, and social cognition

Uncertainty regarding which psychological mechanisms are fundamental in mediating SSRI treatment outcomes and wide-ranging variability in their efficacy has raised more questions than it has solved. Since subjective mood states are an abstract scientific construct, only available through self-report in humans, and likely involving input from multiple top-down and bottom-up signals, it has been difficult to model at what level SSRIs interact with this process. Converging translational evidence indicates a role for serotonin in modulating context-dependent parameters of action selection, affect, and social cognition; and concurrently supporting learning mechanisms, which promote adaptability and behavioural flexibility. We examine the theoretical basis, ecological validity, and interaction of these constructs and how they may or may not exert a clinical benefit. Specifically, we bridge crucial gaps between disparate lines of research, particularly findings from animal models and human clinical trials, which often seem to present irreconcilable differences. In determining how SSRIs exert their effects, our approach examines the endogenous functions of 5-HT neurons, how 5-HT manipulations affect behaviour in different contexts, and how their therapeutic effects may be exerted in humans - which may illuminate issues of translational models, hierarchical mechanisms, idiographic variables, and social cognition.

Theoretical frameworks informing the relationship between parental death and suicidal behaviour: A scoping review

Background

Exposure to parental death in childhood has been strongly associated with offspring suicide although few studies have applied theoretical models to conceptualise this relationship.

Methods

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses – Scoping Reviews guidelines, we conducted a scoping review of primary studies that identified a theory/framework explaining the aetiology of suicidal behaviour in adulthood, following childhood exposure to external-cause parental death, including suicide.

Results

The search yielded 1598 articles. Following full-text screening, 23 studies were identified as meeting inclusion criteria. Data extraction was then completed and found that the studies collectively referenced nine theories. The specific theories identified covered a range of biopsychosocial frameworks and included attachment theory, familial transmission of suicide, conservation of resources framework, diathesis-stress model, social integration theory, socio-ecological model, social learning theory, critical period hypothesis or life course approach and the developmental model of antisocial behaviour.

Limitations

It was beyond the scope of this review to conduct rigorous testing and evaluation of the theories identified. Future research could extend on this study by developing criteria to assess the range of theories and frameworks on suicide exposure, as well as the studies providing evidence for these theories, in order to guide more advanced theory development as well as policies, programs and interventions.

Conclusions

Based on these theories, the authors proposed that using an integrated biopsychosocial model will provide a more comprehensive understanding of the diverse risk and protective factors for suicidal behaviour following parental death.

RDoC and Psychopathology among Youth: Misplaced Assumptions and an Agenda for Future Research

Now over 10 years old, the Research Domain Criteria (RDoC) has gained impressive traction in the adult psychopathology literature, but enthusiasm among child and adolescent psychopathologists lags somewhat behind. We consider possible reasons why RDoC has not been embraced fully in the child and adolescent literatures. We emphasize common, interrelated, and sometimes outdated assumptions that impede scientific progress that RDoC could facilitate. Traditionally, child and adolescent psychopathologists have used behavioral syndromes as gold standards against which biological markers are validated, even though behavioral syndromes are often measured with less precision; sought to identify large main effects of single biological functions on single behavioral syndromes, thereby ignoring (even if implicitly) the overwhelming etiological complexity of psychopathology; expected 1:1 correspondencies between biological functions and behaviors, despite evidence that core biological systems subserving behavior are functionally interdependent (i.e., modulate one another); and failed to consider neurobiological mechanisms of homotypic and heterotypic comorbidity and continuity. Using examples from our work, we show how a developmental, RDoC-informed approach to externalizing behavior enriches our understanding of psychopathology. We also provide an agenda for future research, which includes calls to (1) adopt neural-systems-first approaches over disorder-first approaches when studying psychopathology, (2) eschew biological reductionism by integrating environmental risk mediators into our etiopathophysiological models, (3) integrate neural vulnerabilities into the empirical latent structure of psychopathology, and (4) replace null hypothesis significance testing with computational approaches that accommodate etiological complexity by evaluating functional dependencies among RDoC constructs, including positive valence systems (approach), negative valence systems (avoidance), and arousal/regulatory systems (self-regulation).

Neuroendocrine indicators of allostatic load reveal the impact of environmental acidification in fish

When mobilized from surrounding soils and binding to gills at moderately low pH, aluminum (Al) cations can adversely affect fish populations. Furthermore, acidification may lead to allostatic overload, a situation in which the costs of coping with chronic stress affects long-term survival and reproductive output and, ultimately, ecosystem health. The brain's serotonergic system plays a key role in neuroendocrine stress responses and allostatic processes. Here, we explored whether sublethal effects of Al in acidified water affects serotonergic neurochemistry and stress coping ability in a unique land-locked salmon population from Lake Bygelandsfjorden, in southern Norway. Fish were exposed to untreated water with pH 6.5 and 74 μg Al l^-1 or acidified (pH 5.5) water with different aluminum concentrations ([Al]; 74-148 μg l^-1) for 5-6 days. Afterward, effects on stress coping ability were investigated by analyzing plasma cortisol levels and telencephalic serotonergic neurochemistry before and after a standardized acute stress test. Before the stress test, positive dose-response relationships existed between [Al], serotonergic turnover rate and plasma cortisol. However, in acutely stressed fish, exposure to the highest [Al] resulted in reduced cortisol values compared with those exposed to lower concentrations, while the positive dose-response relationship between Al concentrations and serotonergic turnover rate persisted in baseline conditions. This suggests that fish exposed to the highest Al concentration were unable to mount a proper cortisol response to further acute stress, demonstrating that neuroendocrine indicators of allostatic load can be used to reveal sublethal effects of water acidification-and potentially, the environmental impacts of other factors.

Neurocognitive Adaptation and Mental Health Vulnerability Following Maltreatment: The Role of Social Functioning

Childhood maltreatment is associated with a lifetime increase in risk of mental health disorder. We propose that such vulnerability may stem in large part from altered patterns of social functioning. Here, we highlight key findings from the psychological and epidemiological literature indicating that early maltreatment experience compromises social functioning and attenuates social support in ways that increase mental health vulnerability. We then review the extant neuroimaging studies of children and adolescents, focusing on three domains implicated in social functioning: threat processing, reward processing, and emotion regulation. We discuss how adaptations in these domains may increase latent vulnerability to mental health problems by impacting on social functioning via increased stress susceptibility as well as increased stress generation. Finally, we explore how computational psychiatry approaches, alongside systematically reported measures of social functioning, can complement studies of neural function in the creation of a mechanistic framework aimed at informing approaches to prevention and intervention.

Effect of cooled perches on the efficacy of an induced molt in White Leghorn laying hens previously exposed to heat stress

This study examined the effect of water-chilled perches on hen production and physiological responses to induced molt during elevated temperatures. A total of 288White Leghorns at 82 wk of age were housed in 36 cages of 6 banks. Each bank was assigned to 1 of 3 treatments: cooled perches, air perches, and no perches. The hens were subjected to 2 heat episodes during their first laying cycle at week 21 to 35 and week 73 to 80, respectively. The hens were subjected to a 28 D nonfasted molting regimen starting at 85 wk of age. Cyclic heat of 32°C (6:00 am to 6:00 pm) was applied daily during the molting period. After molt, hens were returned to a layer diet and housed under thermoneutral condition. Two birds per cage were monitored for BW change during molt. Egg production was recorded daily. Feed utilization was measured during molt at 86 and 88 wk of age. Egg weight and eggshell traits were examined at 84 wk (pre-molt) and post-molt at 92, 96, and 104 wk of age. Rectal temperature and blood samples were collected from 2 birds per cage at the end of molt. Blood samples were used for determining heterophil/lymphocyte ratio, corticosterone, and thyroid hormones. Plumage condition was examined at 22 wk post-molt. Compared to control and air perch hens, cooled perch hens had higher feed usage and greater BW loss, lower heterophil/lymphocyte ratios (P < 0.05) with no difference in thyroid hormones and corticosterone at the end of molt. Cooled perch hens also had higher egg production beginning at 98 wk of age (Ptreatment*age < 0.0001) than control hens and sometimes the air-perch hens. Cooled perch hens had higher rectal temperature than control but not air perch hens at end of molt. Moreover, cooled perch hens had better breast feather scores than air perch hens but worse vent plumage (P ≤ 0.05) than both control and air perch hens. These results indicate that the provision of cooled perches assists hens with better adaptation to stressors, such as induced molt plus heat exposure, resulting in improved post-molt egg production.

Approach to stress endocrine response: somatization in the context of gastroenterological symptoms: a systematic review

Background

Stress can be defined as an acute threat to the homeostasis of an organism, and in order to manage stress, and maintain stability, the allostatic systems activate an adaptive response. Stress has been shown to have both short - and long-term effects on the function of the gastrointestinal tract, but long-term exposure to stress is more likely to cause endocrine disorders.

Objective

The aim of this study was to investigate the endocrine response to stress, and evaluate the relationship between somatization and gastrointestinal symptoms.

Methods

A systematic literature search was conducted on several academic databases, which included, Pubmed, EBSCO and Science Direct. The search was performed using the keywords, “endocrine response to stress”, “somatization” and “gastrointestinal symptoms”.

Results

The hypothalamic-pituitary-adrenal (HPA) axis is essential in controlling physiological stress responses. Dysfunction is related to several mental disorders, including anxiety and depression, or somatization. Symptoms associated with genetic, or other traumatic experiences of individuals under stress, can lead to a maladaptive response to stress. These stressful life events were found to be associated with digestive system-related chronic diseases. Gastrointestinal disorders significantly affect millions of people worldwide.

Conclusion

This study examined how the endocrine system responds to stress, and the effect this has in causing stress-related gastrointestinal distresses. Our findings indicate that stress-related psychological disorders are strongly associated with the severity of gastrointestinal symptoms.

Pharmacologically-induced stress has minimal impact on judgement and attention biases in sheep

The emotional impact of exposure to stressors has not been well quantified in animals. We hypothesised that exogenous induction of stress in sheep would induce a pessimistic judgement bias and increased attention towards a threatening stimulus, suggestive of a negative emotional state. Stress was induced pharmacologically by administering synthetic adrenocorticotropic hormone. Judgement bias was assessed using a spatial go/no-go task after exposure to acute stress (one injection), chronic stress (21 daily injections) and acute-on-chronic stress (2 min isolation after 28 daily injections). Attention bias was assessed during chronic stress only (22 daily injections). In contrast with our hypotheses, there was no strong evidence that Synacthen administration altered judgement bias or attention bias at any stage of the experiment. Stressed sheep were more likely to approach ambiguous locations than saline Control animals, however, statistical evidence for models fitting treatment group was very weak. Overall, our findings suggest that elevated levels of cortisol may not fully explain changes to judgement bias observed in previous studies after environmentally-induced stress. Further studies are required to better understand which aspects of environmentally-induced stress alter judgement bias and to further validate cognitive methods of assessing affect in sheep.

Nonsuicidal Self-Injury and Suicidal Behaviors in Girls: The Case for Targeted Prevention in Preadolescence

Non-suicidal self-injury (NSSI) affects 15-20% of adolescents-disproportionately girls-and is a strong predictor of eventual suicide attempts and suicide. Many girls now initiate NSSI before age 10. These early-starters exhibit greater frequency of NSSI, use more diverse methods, and are hospitalized more often, yet there are no empirically supported prevention programs for preadolescents. Obstacles to prevention include ascertaining who is sufficiently vulnerable and specifying mechanistic intervention targets. Recent research indicates that (1) preadolescent girls with ADHD who are also maltreated are at alarming risk for NSSI and suicide attempts by adolescence, and (2) the conjoint effects of these vulnerabilities are sufficiently potent for targeted prevention. Research also indicates that existing interventions are effective in altering child- and family-level mechanisms of NSSI. These interventions alter neurobiological markers of vulnerability, which can be used as proximal efficacy signals of prevention response, without waiting for NSSI and suicide attempts to emerge.

Emotional insecurity as a mediator of the moderating role of dopamine genes in the association between interparental conflict and youth externalizing problems

This study tested whether the association between interparental conflict and adolescent externalizing symptoms was moderated by a polygenic composite indexing low dopamine activity (i.e., 7-repeat allele of DRD4; Val alleles of COMT; 10-repeat variants of DAT1) in a sample of seventh-grade adolescents (Mean age = 13.0 years) and their parents. Using a longitudinal, autoregressive design, observational assessments of interparental conflict at Wave 1 predicted increases in a multi-informant measurement of youth externalizing symptoms 2 years later at Wave 3 only for children who were high on the hypodopaminergic composite. Moderation was expressed in a “for better” or “for worse” form hypothesized by differential susceptibility theory. Thus, children high on the dopaminergic composite experienced more externalizing problems than their peers when faced with more destructive conflicts but also fewer externalizing problems when exposed to more constructive interparental conflicts. Mediated moderation findings indicated that adolescent reports of their emotional insecurity in the interparental relationship partially explained the greater genetic susceptibility experienced by these children. More specifically, the dopamine composite moderated the association between Wave 1 interparental conflict and emotional insecurity 1 year later at Wave 2 in the same “for better” or “for worse” pattern as externalizing symptoms. Adolescent insecurity at Wave 2, in turn, predicted their greater externalizing symptoms 1 year later at Wave 3. Post hoc analyses further revealed that the 7-repeat allele of the dopamine receptor D4 (DRD4) gene was the primary source of plasticity in the polygenic composite. Results are discussed as to how they advance process-oriented Gene x Environment models of emotion regulation.

Chronic stress influences attentional and judgement bias and the activity of the HPA axis in sheep

INTRODUCTION

Environmental challenges are part of everyday life for most domestic animals. However, very little is known about how animals cope emotionally and physiologically with cumulative challenges. This experiment aimed to determine the impact of long-term exposure to environmental challenges on the affective state and hypothalamic-pituitary-adrenal (HPA) axis responses to a subsequent additional acute shearing challenge.

METHODS

Sheep were exposed to either a long-term environmental challenge (rest disruption and individual housing) in order to induce chronic stress (chronic stress group) or control conditions (group housing in a field with low stress handling and daily feed rewards, control group). Judgement and attention bias were assessed as measures of the emotional state following several days of the challenge or control treatment (pre-shearing tests). In addition, the responsiveness of the HPA-axis was evaluated using a combined Corticotropin Releasing Hormone and Arginine Vasopressin (CRH/AVP) challenge. Finally, all animals were exposed to an acute shearing challenge, then judgement bias (post-shearing test), HPA-axis and internal body temperature responses were determined.

RESULTS

In the pre-shearing judgement bias test, the chronic stress group slightly increased optimism compared to the control treatment. In the attention bias test, the chronic stress group showed reduced vigilance behaviour towards a predator threat and a quicker approach to the food compared to the control treatment. The chronic stress group also had lower plasma ACTH concentrations in response to the CRH/AVP challenge compared to the control group, no differences in cortisol concentrations were found. In the post-shearing judgement bias test, differences in optimism were no longer evident between the chronic stress and control groups. Plasma ACTH concentrations and body temperatures showed a greater increase in response to shearing in the chronic stress group compared to the control group.

CONCLUSION

Our results suggest that long-term exposure to challenges biased cognitive measures of the affective state towards an increased expectation of a reward and reduced attention towards a threat. The exaggerated ACTH responses in the chronic stress group may be indicative of HPA-axis dysregulation. Despite a period of challenge exposure in the chronic stress group, judgement bias responses to the shearing challenge were similar in the chronic stress and control groups; the reasons for this need further investigation. The altered affective state together with signs of HPA-axis dysregulation may indicate an increased risk of compromised welfare in animals exposed to long-term environmental challenges.

Psychiatry and developmental psychopathology: Unifying themes and future directions

In the past 35 years, developmental psychopathology has grown into a flourishing discipline that shares a scientific agenda with contemporary psychiatry. In this editorial, which introduces the special issue, we describe the history of developmental psychopathology, including core principles that bridge allied disciplines. These include (1) emphasis on interdisciplinary research, (2) elucidation of multicausal pathways to seemingly single disorders (phenocopies), (3) description of divergent multifinal outcomes from common etiological start points (pathoplasticity), and (4) research conducted across multiple levels of analysis spanning genes to environments. Next, we discuss neurodevelopmental models of psychopathology, and provide selected examples. We emphasize differential neuromaturation of subcortical and cortical neural networks and connectivity, and how both acute and protracted environmental insults can compromise neural structure and function. To date, developmental psychopathology has placed greater emphasis than psychiatry on neuromaturational models of mental illness. However, this gap is closing rapidly as advances in technology render etiopathophysiologies of psychopathology more interrogable. We end with suggestions for future interdisciplinary research, including the need to evaluate measurement invariance across development, and to construct more valid assessment methods where indicated.

A pilot investigation of differential neuroendocrine associations with fronto-limbic activation during semantically-cued list learning in mood disorders

BACKGROUND

Decreased volume and disrupted function in neural structures essential for memory formation (e.g. medial temporal lobe and prefrontal cortex) are common among individuals with depression. Hypothalamic-pituitary-axis function, as reflected by measurement of cortisol levels, is linked to neural activity during memory encoding in healthy people. However, it is not as well understood whether cortisol is associated with alterations in fronto-temporal recruitment during memory encoding in depression.

METHODS

In this pilot study, we evaluated associations between cortisol and neural activation during memory encoding in 62 adults (18-65 years) with mood disorders (MD; n = 39, 66.7% female), including major depression (n = 28) and bipolar I disorder (n = 11), and healthy controls (HC; n = 23, 43.5% female). Participants provided salivary cortisol samples before and after completing a semantically-cued list-learning task during 3-Tesla fMRI. Links between pre-scan cortisol (and cortisol change) and activation during encoding were evaluated using block and event-related models.

RESULTS

Overall, pre-scan cortisol level was positively associated with greater engagement of fronto-limbic activation during the encoding block. However, in MD, pre-scan cortisol was associated with attenuated activation during encoding in medial frontal, superior and middle temporal gyri, insula, lingual gyrus, and claustrum relative to HCs. Cortisol-related attenuation of activation in MD was also observed during encoding of words subsequently recalled in the ventral anterior cingulate, hypothalamus, and middle temporal gyrus. By and large, cortisol change (pre/post scan) predicted the same pattern of findings in both block and event-related contrasts.

LIMITATIONS

Although analyses accounted for variations in scanner time of day, circadian alterations in cortisol may have introduced variability into the results.

CONCLUSIONS

Pre-scan cortisol may selectively interfere with recruitment of important fronto-temporal memory circuitry in mood disorders. The inverted associations between cortisol and neural function in MD relative to HC also elucidate potentially unique pathophysiological markers of mood disorders.

Community-level Adverse Experiences and Emotional Regulation in Children and Adolescents

PURPOSE

The association of adverse childhood experiences (ACEs) with negative health outcomes is well established, and the concept of allostatic load has been proposed as a possible causal mechanism. Most studies measure conventional (household) ACE exposures without accounting for non-conventional (community) ACE exposures, which may underrepresent the adversity experienced by racial/ethnic minorities. We address this gap by calculating the prevalence of both types of ACE exposures for racial/ethnic subgroups. We also examine associations of ACE exposures and emotional regulation in school aged children and youth.

DESIGN AND METHODS

This study used data (n = 65,680) for a nationally representative sample of children ages 6 to 17 years in the National Survey of Children's Health (2011-2012). Confirmatory factor analysis, descriptive statistics and regression models were used to examine the relationships between ACEs and emotional regulation.

RESULTS

Community level ACE events disproportionately affect ethnic minorities. Some but not all ACEs were significantly and inversely associated with the ability to emotionally regulate in children. Experiencing racism had the strongest negative effect of all ACE variables. The strength of the child-caregiver relationship was associated with increased odds of emotional regulation, independent of exposure to ACEs.

CONCLUSIONS

The study supports the need to refine and expand ACE health screenings to fully capture the adversity faced by all children. Emotional regulation is identified as a possible intervention point.

PRACTICE IMPLICATIONS

Expansion of programs that strengthen the child-caregiver relationship and reduce ACEs in early childhood may be a key approach to increasing coping abilities in youth.

Perceived school safety, perceived neighborhood safety, and insufficient sleep among adolescents

OBJECTIVES

To examine whether perceptions of school safety and neighborhood safety are associated with insufficient sleep during adolescence.

DESIGN

The Florida Youth Substance Abuse Survey (FYSAS) is a cross-sectional study of adolescents.

SETTING

The state of Florida.

PARTICIPANTS

Middle-school and high-school students (n = 7,958) attending public schools in 2017.

MEASUREMENTS

Based on National Sleep Foundation recommendations, sleep was categorized as insufficient (less than 7 hours) or sufficient (7 or more hours) using self-reports of average sleep duration on school nights. Self-reports of perceived safety at school and perceived safety in one's neighborhood were modeled as predictors of insufficient sleep in logistic regression models when accounting for several covariates.

RESULTS

Adjusting for model covariates, the odds of insufficient sleep among adolescents who feel unsafe both at school and in their neighborhood are 129% greater relative to adolescents who feel safe in both contexts. In comparison, the odds of insufficient sleep among adolescents who feel unsafe only at school are 39% greater relative to adolescents who feel safe both at school and in their neighborhood, and the odds of insufficient sleep among adolescents who feel unsafe only in their neighborhood are 71% greater relative to adolescents who feel safe both at school and in their neighborhood.

CONCLUSIONS

The findings of this study indicate that efforts to improve the safety of salient social contexts in which adolescents develop may reduce the likelihood of insufficient sleep faced by a large portion of school-aged children.

Growing a social brain

It has long been assumed that social animals, such as humans, are born with a brain system that has evolved to support social affiliation. However, the evidence does not necessarily support this assumption. Alternatively, social animals can be defined as those who cannot survive alone and rely on members from their group to regulate their ongoing physiology (or allostasis). The rather simple evolutionary constraint of social dependency for survival can be sufficient to make the social environment vitally salient, and to provide the ultimate driving force for socially crafted brain development and learning. In this Perspective, we propose a framework for sociality and specify a set of hypotheses on the mechanisms of social development and underlying neural systems. The theoretical shift proposed here implies that profound human characteristics, including but not limited to sociality, are acquired at an early age, while social interactions provide key wiring instructions that determine brain development.

Incorporating epigenetic mechanisms to advance fetal programming theories

Decades of fetal programming research indicates that we may be able to map the origins of many physical, psychological, and medical variations and morbidities before the birth of the child. While great strides have been made in identifying associations between prenatal insults, such as undernutrition or psychosocial stress, and negative developmental outcomes, far less is known about how adaptive responses to adversity regulate the developing phenotype to match stressful conditions. As the application of epigenetic methods to human behavior has exploded in the last decade, research has begun to shed light on the role of epigenetic mechanisms in explaining how prenatal conditions shape later susceptibilities to mental and physical health problems. In this review, we describe and attempt to integrate two dominant fetal programming models: the cumulative stress model (a disease-focused approach) and the match-mismatch model (an evolutionary-developmental approach). In conjunction with biological sensitivity to context theory, we employ these two models to generate new hypotheses regarding epigenetic mechanisms through which prenatal and postnatal experiences program child stress reactivity and, in turn, promote development of adaptive versus maladaptive phenotypic outcomes. We conclude by outlining priority questions and future directions for the fetal programming field.

Assessment of depression-like behavior and anhedonia after repeated cycles of binge-like ethanol drinking in male C57BL/6J mice

Psychological depression is frequently linked to alcohol abuse and even serves as key indicators of an alcohol use disorder (AUD). This relationship is supported by preclinical findings in which depression-like phenotypes develop in animals exposed to chronic intermittent ethanol vapor, a common preclinical model of alcohol dependence. However, the emergence of these maladaptive phenotypes following repeated binge-like ethanol drinking remains relatively unexplored. The purpose of this study was to evaluate depression-like behaviors associated with binge-like consumption in mice. Using the drinking-in-the-dark (DID) paradigm, we examined the impact of multiple binge-like cycles (1, 3, or 6) on depression-like behaviors in the forced swim test (FST) and sucrose preference as a test for anhedonia. We also assessed the effect of repeated binge cycles on the consumption of bitter and sweet tastants over a range of concentrations. Results indicated that binge-like ethanol drinking did not lead to depression-like behavior as repeated cycles of DID did not alter sucrose consumption or preference nor did it impact time spent immobile during the FST. Animals that experienced six cycles of DID showed increased quinine consumption and increased quinine preference, which may be indicative of an escalated preference for tastants that resemble the gustatory aspects of ethanol. Interestingly, an unexpected ~20% increase in hypermobility was observed after three cycles of binge-like ethanol drinking. Although the FST is most frequently used to model depression-like behavior, emerging evidence suggests that increased hypermobility during the FST could be indicative of an inability to cope in a stressful situation, suggesting that repeated ethanol exposure in the present experiment transiently enhances stress reactivity.

Allostatic Load and Stress Physiology in European Seabass (Dicentrarchus labrax L.) and Gilthead Seabream (Sparus aurata L.)

The present study aimed to compare effects of increasing chronic stress load on the stress response of European seabass (Dicentrarchus labrax) and gilthead seabream (Sparus aurata) to identify neuroendocrine functions that regulate this response. Fish were left undisturbed (controls) or exposed to three levels of chronic stress for 3 weeks and then subjected to an acute stress test (ACT). Chronic stress impeded growth and decreased feed consumption in seabass, not in seabream. In seabass basal cortisol levels are high and increase with stress load; the response to a subsequent ACT decreases with increasing (earlier) load. Basal cortisol levels in seabream increase with the stress load, whereas the ACT induced a similar response in all groups. In seabass and seabream plasma α-MSH levels and brain stem serotonergic activity and turnover were similar and not affected by chronic stress. Species-specific molecular neuro-regional differences were seen. In-situ hybridization analysis of the early immediate gene cfos in the preoptic area showed ACT-activation in seabream; in seabass the expression level was not affected by ACT and seems constitutively high. In seabream, expression levels of telencephalic crf, crfbp, gr1, and mr were downregulated; the seabass hypothalamic preoptic area showed increased expression of crf and gr1, and decreased expression of mr, and this increased the gr1/mr ratio considerably. We substantiate species-specific physiological differences to stress coping between seabream and seabass at an endocrine and neuroendocrine molecular level. Seabass appear less resilient to stress, which we conclude from high basal activities of stress-related parameters and poor, or absent, responses to ACT. This comparative study reveals important aquaculture, husbandry, and welfare implications for the rearing of these species.

Targeting couple and parent-child coercion to improve health behaviors

This phase of the NIH Science of Behavior Change program emphasizes an "experimental medicine approach to behavior change," that seeks to identify targets related to stress reactivity, self-regulation, and social processes for maximal effects on multiple health outcomes. Within this framework, our project focuses on interpersonal processes associated with health: coercive couple and parent-child conflict. Diabetes and poor oral health portend pain, distress, expense, loss of productivity, and even mortality. They share overlapping medical regimens, are driven by overlapping proximal health behaviors, and affect a wide developmental span, from early childhood to late adulthood. Coercive couple and parent-child conflict constitute potent and destructive influences on a wide range of adult and child health outcomes. Such interaction patterns give rise to disturbed environmental stress reactivity (e.g., disrupted sympathetic nervous and parasympathetic nervous systems) and a wide range of adverse health outcomes in children and adults, including dental caries, obesity, and diabetes-related metabolic markers. In this work, we seek to identify/develop/validate assays assessing coercion, identify/develop and test brief interventions to reduce coercion, and test whether changes in coercion trigger changes in health behaviors.

Bio-behavioral synchrony promotes the development of conceptualized emotions

As adults, we have structured conceptual representations of our emotions that help us to make sense of and regulate our ongoing affective experience. The ability to use emotion concepts is critical to make predictions about the world and choose appropriate action, such as 'I am afraid, and going to run away' or 'I am hungry and going to eat'. Thus, emotion concepts have an important role in helping us maintain our ongoing physiological balance, or allostasis. We will suggest here that infants can learn emotion concepts for the purpose of allostasis regulation, and that conceptualization is key component in emotional development. Moreover, we will suggest that social dyads facilitate concept learning because of a robust evolutionary feature seen in newborns of social species: they cannot survive alone and depend on conspecifics for allostasis regulation. Such social dependency creates a robust driving force for social learning of emotion concepts, and makes the social dyad, which is designed to regulate the infant's allostasis, an optimal medium for concept learning. In line with that, we will review evidence showing that the neural reference space for emotion overlaps with neural circuits that support allostasis (striatum, amygdala, and hypothalamus) and conceptualization (medial prefrontal cortex, posterior cingulate cortex), and that their developmental trajectories are interrelated, and depend on synchronous social care.

Redefining the endophenotype concept to accommodate transdiagnostic vulnerabilities and etiological complexity

In psychopathology research, endophenotypes are a subset of biomarkers that indicate genetic vulnerability independent of clinical state. To date, an explicit expectation is that endophenotypes be specific to single disorders. We evaluate this expectation considering recent advances in psychiatric genetics, recognition that transdiagnostic vulnerability traits are often more useful than clinical diagnoses in psychiatric genetics, and appreciation for etiological complexity across genetic, neural, hormonal and environmental levels of analysis. We suggest that the disorder-specificity requirement of endophenotypes be relaxed, that neural functions are preferable to behaviors as starting points in searches for endophenotypes, and that future research should focus on interactive effects of multiple endophenotypes on complex psychiatric disorders, some of which are ‘phenocopies’ with distinct etiologies.

Allostatic load and comorbidities: A mitochondrial, epigenetic, and evolutionary perspective

Stress-related pathophysiology drives comorbid trajectories that elude precise prediction. Allostatic load algorithms that quantify biological "wear and tear" represent a comprehensive approach to detect multisystemic disease processes of the mind and body. However, the multiple morbidities directly or indirectly related to stress physiology remain enigmatic. Our aim in this article is to propose that biological comorbidities represent discrete pathophysiological processes captured by measuring allostatic load. This has applications in research and clinical settings to predict physical and psychiatric comorbidities alike. The reader will be introduced to the concepts of allostasis, allostasic states, allostatic load, and allostatic overload as they relate to stress-related diseases and the proposed prediction of biological comorbidities that extend rather to understanding psychopathologies. In our transdisciplinary discussion, we will integrate perspectives related to (a) mitochondrial biology as a key player in the allostatic load time course toward diseases that "get under the skin and skull"; (b) epigenetics related to child maltreatment and biological embedding that shapes stress perception throughout lifespan development; and

Neural substrates of trait impulsivity, anhedonia, and irritability: Mechanisms of heterotypic comorbidity between externalizing disorders and unipolar depression

Trait impulsivity, which is often defined as a strong preference for immediate over delayed rewards and results in behaviors that are socially inappropriate, maladaptive, and short-sighted, is a predisposing vulnerability to all externalizing spectrum disorders. In contrast, anhedonia is characterized by chronically low motivation and reduced capacity to experience pleasure, and is common to depressive disorders. Although externalizing and depressive disorders have virtually nonoverlapping diagnostic criteria in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, heterotypic comorbidity between them is common. Here, we review common neural substrates of trait impulsivity, anhedonia, and irritability, which include both low tonic mesolimbic dopamine activity and low phasic mesolimbic dopamine responding to incentives during reward anticipation and associative learning. We also consider how other neural networks, including bottom-up emotion generation systems and top-down emotion regulation systems, interact with mesolimbic dysfunction to result in alternative manifestations of psychiatric illness. Finally, we present a model that emphasizes a translational, transdiagnostic approach to understanding externalizing/depression comorbidity. This model should refine ways in which internalizing and externalizing disorders are studied, classified, and treated.

Review on Neural Correlates of Emotion Regulation and Music: Implications for Emotion Dysregulation

Previous studies have examined the neural correlates of emotion regulation and the neural changes that are evoked by music exposure. However, the link between music and emotion regulation is poorly understood. The objectives of this review are to (1) synthesize what is known about the neural correlates of emotion regulation and music-evoked emotions, and (2) consider the possibility of therapeutic effects of music on emotion dysregulation. Music-evoked emotions can modulate activities in both cortical and subcortical systems, and across cortical-subcortical networks. Functions within these networks are integral to generation and regulation of emotions. Since dysfunction in these networks are observed in numerous psychiatric disorders, a better understanding of neural correlates of music exposure may lead to more systematic and effective use of music therapy in emotion dysregulation.

Trait Impulsivity and the Externalizing Spectrum

This article reviews evidence that trait impulsivity-expressed early in life as the hyperactive-impulsive and combined presentations of attention-deficit/hyperactivity disorder (ADHD)-is a bottom-up, subcortically mediated vulnerability to all externalizing disorders. This vulnerability arises from deficient mesolimbic dopamine responding, which imbues psychological states (irritability, discontentment) that motivate excessive approach behavior (hyperactivity, impulsivity). Through complex interactions with (a) aversive motivational states that arise from largely independent subcortical systems, (b) emotion regulatory mechanisms that arise from top-down, cortical modulation of subcortical neural function, and (c) environmental risk factors that shape and maintain emotion dysregulation, trait impulsivity confers vulnerability to increasingly severe externalizing behaviors across development. This perspective highlights the importance of identifying transdiagnostic neural vulnerabilities to psychopathology; dovetails with the hierarchical, latent structure of psychopathology; and suggests that progression along the externalizing spectrum is an ontogenic process whereby a common, multifactorially inherited trait interacts with endogenous and exogenous influences to yield increasingly intractable externalizing behaviors across development.

Early caregiving stress exposure moderates the relation between respiratory sinus arrhythmia reactivity at 1 month and biobehavioral outcomes at age 3

There is a growing scientific interest in the psychophysiological functioning of children living in low-socioeconomic status (SES) contexts, though this research is complicated by knowledge that physiology-behavior relations often operate differently in these environments among adults. Importantly, such research is made more difficult because SES may be a proxy for a wide range of risk factors including poor caregiving and exposure to parental substance use. We used factor analysis to organize risk-exposure data collected from 827 children-many of whom were raised in low-SES contexts and exposed to substances prenatally-into dissociable components including economic stress, caregiving stress (e.g., stress the caregiver may experience, including parental psychopathology), and postnatal substance exposure. These factors, along with respiratory sinus arrhythmia (RSA) reactivity at age 1 month, were used to predict behavior dysregulation and resting RSA at age 3 years. A significant RSA Reactivity × Caregiving Stress interaction indicated that infants who exhibited high RSA reactivity at 1 month experienced the greatest behavior dysregulation at 3 years, but only when they were exposed to high levels of caregiving stress. Among African Americans, the highest resting RSA at 3 years was found in infants with less RSA reactivity, but only if they also experienced less caregiving stress. Our work is consistent with biological sensitivity to context, adaptive calibration, and allostatic load models, and highlights the importance of studying Physiology × Environment interactions in low-SES contexts for predicting behavior and resting RSA.

Enduring, Sexually Dimorphic Impact of In Utero Exposure to Elevated Levels of Glucocorticoids on Midbrain Dopaminergic Populations

Glucocorticoid hormones (GCs) released from the fetal/maternal glands during late gestation are required for normal development of mammalian organs and tissues. Accordingly, synthetic glucocorticoids have proven to be invaluable in perinatal medicine where they are widely used to accelerate fetal lung maturation when there is risk of pre-term birth and to promote infant survival. However, clinical and pre-clinical studies have demonstrated that inappropriate exposure of the developing brain to elevated levels of GCs, either as a result of clinical over-use or after stress-induced activation of the fetal/maternal adrenal cortex, is linked with significant effects on brain structure, neurological function and behaviour in later life. In order to understand the underlying neural processes, particular interest has focused on the midbrain dopaminergic systems, which are critical regulators of normal adaptive behaviours, cognitive and sensorimotor functions. Specifically, using a rodent model of GC exposure in late gestation (approximating human brain development at late second/early third trimester), we demonstrated enduring effects on the shape and volume of the ventral tegmental area (VTA) and substantia nigra pars compacta (SNc) (origins of the mesocorticolimbic and nigrostriatal dopaminergic pathways) on the topographical organisation and size of the dopaminergic neuronal populations and astrocytes within these nuclei and on target innervation density and neurochemical markers of dopaminergic transmission (receptors, transporters, basal and amphetamine-stimulated dopamine release at striatal and prefrontal cortical sites) that impact on the adult brain. The effects of antenatal GC treatment (AGT) were both profound and sexually-dimorphic, not only in terms of quantitative change but also qualitatively, with several parameters affected in the opposite direction in males and females. Although such substantial neurobiological changes might presage marked behavioural effects, in utero GC exposure had only a modest or no effect, depending on sex, on a range of conditioned and unconditioned behaviours known to depend on midbrain dopaminergic transmission. Collectively, these findings suggest that apparent behavioural normality in certain tests, but not others, arises from AGT-induced adaptations or compensatory mechanisms within the midbrain dopaminergic systems, which preserve some, but not all functions. Furthermore, the capacities for molecular adaptations to early environmental challenge are different, even opponent, in males and females, which may account for their differential resilience or failure to perform adequately in behavioural tests. Behavioural "normality" is thus achieved by the midbrain dopaminergic network operating outside its normal limits (in a state of allostasis), rendering it at greater risk to malfunction when challenged in later life. Sex-specific neurobiological programming of midbrain dopaminergic systems may, therefore, have psychopathological relevance for the sex bias commonly found in brain disorders associated with these systems, and which have a neurodevelopmental component, including schizophrenia, ADHD (attention/deficit hyperactivity disorders), autism, depression and substance abuse.

Biting the hand that feeds: current opinion on the interpersonal causes, correlates, and consequences of borderline personality disorder

Borderline personality disorder (BPD) is a complex psychiatric diagnosis characterized by dysregulated behaviors, emotions, cognitions, and interpersonal relationships. In recent years, developmental psychopathologists have sought to identify early origins of BPD, with the ultimate goal of developing and providing effective preventative interventions for those at highest risk. In addition to heritable biological sensitivities, many scholars assert that environmental and interpersonal risk factors contribute to the emergence and maintenance of key borderline traits. Nonetheless, many BPD researchers examine only affected individuals, neglecting the family, peer, couple, and other dynamic contextual forces that impinge upon individual-level behavior. In the past decade, however, theoretical and empirical research has increasingly explored the interpersonal causes, correlates, and consequences of BPD. Such work has resulted in novel research and clinical theories intended to better understand and improve interpersonal dynamics among those with borderline traits. A major objective for the field is to better characterize how interpersonal dynamics affect (and are affected by) the behaviors, emotions, and thoughts of vulnerable individuals to either reduce or heighten risk for BPD.

Effects of acute and chronic stress on telencephalic neurochemistry and gene expression in rainbow trout (Oncorhynchus mykiss)

By filtering relevant sensory inputs and initiating stress responses, the brain is an essential organ in stress coping and adaptation. However, exposure to chronic or repeated stress can lead to allostatic overload, where neuroendocrinal and behavioral reactions to stress become maladaptive. This work examines forebrain mechanisms involved in allostatic processes in teleost fishes. Plasma cortisol, forebrain serotonergic (5-HTergic) neurochemistry, and mRNA levels of corticotropin-releasing factor (CRF), CRF-binding protein (CRF-BP), CRF receptors (CRFR1 and CRFR2), mineralocorticoid receptor (MR), glucocorticoid receptors (GR1 and GR2) and serotonin type 1A (5-HT_1A) receptors (5-HT_1Aα and 5-HT_1Aβ) were investigated at 1 h before and 0, 1 and 4 h after acute stress, in two groups of rainbow trout held in densities of 25 and 140 kg m^-3 for 28 days. Generally, being held at 140 kg m^-3 resulted in a less pronounced cortisol response. This effect was also reflected in lower forebrain 5-HTergic turnover, but not in mRNA levels in any of the investigated genes. This lends further support to reports that allostatic load causes fish to be incapable of mounting a proper cortisol response to an acute stressor, and suggests that changes in forebrain 5-HT metabolism are involved in allostatic processes in fish. Independent of rearing densities, mRNA levels of 5-HT_1Aα and MR were downregulated 4 h post-stress compared with values 1 h post-stress, suggesting that these receptors are under feedback control and take part in the downregulation of the hypothalamic-pituitary-interrenal (HPI) axis after exposure to an acute stressor.

Childhood adversities and risk for problematic alcohol use

The findings from studies exploring the relationship between childhood adversities (CAs) and adolescent and adult drinking problems are inconclusive - some researchers have found strong effects, others virtually none. In this study, we sought to examine the associations between 23 types of retrospectively reported CAs and adult problematic alcohol use in two samples, one drawn from Germany, the other from Poland. A total sample of 1008 participants was recruited via the internet: 500 in Germany and 508 in Poland. They completed a set of questionnaires including questions regarding various types of CA, and also the CAGE tool for the identification of problem drinking. CAs were grouped into four categories: Negative Personal Experience, Family Adversities, Parental Disorders, Parent-Child Relationships; this last category included role reversal. Separate logistic regression analyses were performed, with age, gender and country as potential confounders. The probability of having an alcohol problem was higher in men, and higher in Poland than in Germany. Of the risk factors tested, three displayed a significant association with problematic alcohol use. The risk factors concerned were Regular Arguments Between the Parents, plus two types of adversities from the Parent-Child Relationships cluster: Maternal Control and Maternal Role Reversal. The results serve to underline the importance of examining links between childhood risk factors and problematic alcohol use, and also suggest that certain less visible symptoms of a disordered parent-child (particularly mother-child) relationship, such as parentification, may constitute important risk factors for the development of drinking problems in later life.

Where Do Epigenetics and Developmental Origins Take the Field of Developmental Psychopathology?

The time is ripe for upgrading or rethinking the assumed paradigms for how we study developmental psychopathology. The classic transactional models appear robust but need specification in terms of biological and psychosocial processes. That specification is increasingly tractable due to developments in genetics, epigenetics, the measurement of psychosocial processes, and theory and data on developmental origins of health and disease. This essay offers a high-level view of where the field has been and where it may be going in regard to nosology and conceptions of etiology. Remarks seek to consider rapidly evolving contexts not only for children, but also for the science itself due to progress in our field and in neighboring fields. Illustrations are provided as to how syndromal nosology can be enriched and advanced by careful integration with biologically relevant behavioral dimensions and application of quantitative methods. It is concluded that a revised, forward-looking, transactional model of abnormal child psychology will incorporate prenatal and postnatal developmental programming, epigenetic mechanisms and their associated genotype x environment interactions, and inflammatory processes as a potential common mediator influencing numerous health and mental health conditions.