Social stress buffering by friends in childhood and adolescence: Effects on HPA and oxytocin activity

The lateral habenula integrates age and experience to promote social transitions in developing rats

Early caregiving adversity (ECA) is associated with social behavior deficits and later development of psychopathology. However, the infant neural substrates of ECA are poorly understood. The lateral habenula (LHb), a highly conserved brain region with consistent links to adult psychopathology, is understudied in development, when the brain is most vulnerable to environmental impacts. Here, we describe the structural and functional ontogeny of the LHb and its behavioral role in infant and juvenile rat pups. We show that the LHb promotes a developmental transition in social approach behavior under threat as typically reared infants mature. By contrast, we show that ECA disrupts habenular ontogeny, including volume, protein expression, firing properties, and corticohabenular connectivity. Furthermore, inhibiting a specific corticohabenular projection rescues infant social approach deficits following ECA. Together, these results identify immediate biomarkers of ECA in the LHb and highlight this region as a site of early social processing and behavior control.

Early adolescent perceived friendship quality aids affective and neural responses to social inclusion and exclusion in young adults with and without adverse childhood experiences

Friendships increase mental wellbeing and resilient functioning in young people with childhood adversity (CA). However, the mechanisms of this relationship are unknown. We examined the relationship between perceived friendship quality at age 14 after the experience of CA and reduced affective and neural responses to social exclusion at age 24. Resilient functioning was quantified as psychosocial functioning relative to the degree of CA severity in 310 participants at age 24. From this cohort, 62 young people with and without CA underwent functional Magnetic Resonance Imaging to assess brain responses to social inclusion and exclusion. We observed that good friendship quality was significantly associated with better resilient functioning. Both friendship quality and resilient functioning were related to increased affective responses to social inclusion. We also found that friendship quality, but not resilient functioning, was associated with increased dorsomedial prefrontal cortex responses to peer exclusion. Our findings suggest that friendship quality in early adolescence may contribute to the evaluation of social inclusion by increasing affective sensitivity to positive social experiences and increased brain activity in regions involved in emotion regulation to negative social experiences. Future research is needed to clarify this relationship with resilient functioning in early adulthood.

Social networks and violence victimization and perpetration among youth: A longitudinal analysis

Interpersonal violence (IV) is a serious concern for adolescents in the United States that has devastating impacts for individuals and communities. Given the increased importance placed on friendships during adolescence, the purpose of the current study was to examine the extent to which IV experiences cluster within youths' friendship networks. Participants were students (N = 1303) in grades 7th to 10th who completed surveys at the beginning and end of an academic year. Results showed that friends' average perpetration (i.e., the percentage of the friends they nominated who perpetrated IV) was strongly associated with likelihood of individual perpetration at baseline but not at the follow-up. For victimization, friends' average report of victimization (i.e., the percentage of the friends they nominated who were victimized) was associated with higher likelihood reporting of victimization (at both baseline and follow-up). Although future research is needed to understand explanatory mechanisms underlying these findings, it is possible that the effectiveness of prevention initiatives may be enhanced by incorporating peer group information.

The lateral habenula integrates age and experience to promote social transitions in developing rats

Social behavior deficits are an early-emerging marker of psychopathology and are linked with early caregiving quality. However, the infant neural substrates linking early care to social development are poorly understood. Here, we focused on the infant lateral habenula (LHb), a highly-conserved brain region at the nexus between forebrain and monoaminergic circuits. Despite its consistent links to adult psychopathology, this brain region has been understudied in development when the brain is most vulnerable to environmental impacts. In a task combining social and threat cues, suppressing LHb principal neurons had opposing effects in infants versus juveniles, suggesting the LHb promotes a developmental switch in social approach behavior under threat. We observed that early caregiving adversity (ECA) disrupts typical growth curves of LHb baseline structure and function, including volume, firing patterns, neuromodulatory receptor expression, and functional connectivity with cortical regions. Further, we observed that suppressing cortical projections to the LHb rescued social approach deficits following ECA, identifying this microcircuit as a substrate for disrupted social behavior. Together, these results identify immediate biomarkers of ECA in the LHb and highlight this region as a site of early social processing and behavior control.

The Development of Stress Reactivity and Regulation in Children and Adolescents

Adversity experienced in early life can have detrimental effects on physical and mental health. One pathway in which these effects occur is through the hypothalamic-pituitary-adrenal (HPA) axis, a key physiological stress-mediating system. In this review, we discuss the theoretical perspectives that guide stress reactivity and regulation research, the anatomy and physiology of the axis, developmental changes in the axis and its regulation, brain systems regulating stress, the role of genetic and epigenetics variation in axis development, sensitive periods in stress system calibration, the social regulation of stress (i.e., social buffering), and emerging research areas in the study of stress physiology and development. Understanding the development of stress reactivity and regulation is crucial for uncovering how early adverse experiences influence mental and physical health.

Stress Biomarkers in Black Youth: Exploring Psychological, Behavioral, and Socio-Ecological Correlates

Exposure to chronic stress is a major public health concern. Black youth are vulnerable to chronic stress exposure given their overrepresentation in urban neighborhoods characterized by socio-ecological stressors. We contribute to this emerging body of knowledge by (1) investigating stress-induced variability in cortisol response patterns among Black youth, and (2) examining risk and protective factors associated with physiological stress responses. Salivary cortisol was collected from a community sample of 123 low-income Black youth ages 13 to 21. Latent class analysis (LCA) and logistic regression were utilized to identify discrete groups based on cortisol reactivity, and psychological, behavioral, and socio-ecological correlates of class membership. LCA supported a 2-class model of cortisol reactivity. Youth in class one were indicative of a normative stress response with mean cortisol awakening response of 0.38 μg/dL (SD = 0.19), 0.48 μg/dL (SD = 0.20) at time 2, and 0.44 μg/dL (SD = 0.20) at time 3. Youth in class two exhibited a blunted stress response with mean cortisol awakening response of 0.20 μg/dL (SD = 0.11), 0.21 μg/dL (SD = 0.09) at time 2, and 0.18 μg/dL (SD = 0.08) at time 3. Delinquent peer exposure and post-traumatic stress symptoms were negatively associated with blunted stress responses, while greater depressive symptoms were positively associated with blunted stress responses. Black youth displayed distinct physiological stress reactivity patterns. Interventions are needed to assist youth in coping with stress while transforming the upstream factors that give rise to adverse community conditions.

Peer facilitation of emotion regulation in adolescence

Emotion regulation is particularly important for adolescents as they undergo normative developmental changes in affective systems and experience heightened risk for psychopathology. Despite a high need for emotion regulation during adolescence, commonly studied emotion regulation strategies like cognitive reappraisal are less beneficial for adolescents than adults because they rely on neural regions that are still developing during this period (i.e., lateral prefrontal cortex). However, adolescence is also marked by increased valuation of peer relationships and sensitivity to social information and cues. In the present review, we synthesize research examining emotion regulation and peer influence across development to suggest that sensitivity to peers during adolescence could be leveraged to improve emotion regulation for this population. We first discuss developmental trends related to emotion regulation at the level of behavior and brain in adolescents, using cognitive reappraisal as an exemplar emotion regulation strategy. Next, we discuss social influences on adolescent brain development, describing caregiver influence and increasing susceptibility to peer influence, to describe how adolescent sensitivity to social inputs represents both a window of vulnerability and opportunity. Finally, we conclude by describing the promise of social (i.e., peer-based) interventions for enhancing emotion regulation in adolescence.

Advances in human oxytocin measurement: challenges and proposed solutions

Oxytocin, a neuropeptide known for its role in reproduction and socioemotional processes, may hold promise as a therapeutic agent in treating social impairments in patient populations. However, research has yet to uncover precisely how to manipulate this system for clinical benefit. Moreover, inconsistent use of standardized and validated oxytocin measurement methodologies-including the design and study of hormone secretion and biochemical assays-present unresolved challenges. Human studies measuring peripheral (i.e., in plasma, saliva, or urine) or central (i.e., in cerebrospinal fluid) oxytocin concentrations have involved very diverse methods, including the use of different assay techniques, further compounding this problem. In the present review, we describe the scientific value in measuring human endogenous oxytocin concentrations, common issues in biochemical analysis and study design that researchers face when doing so, and our recommendations for improving studies using valid and reliable methodologies.

Relationship between proximity and physiological stress levels in hunter-gatherers: The Hadza

In recent years there has been a great deal of documentation on how social relationships are related to various aspects of human wellbeing. However, until recently most studies investigating the effects of social relationships on wellbeing have applied social network measures to reported social contacts. Recent advances in the application of bio-loggers in biological studies have now made it possible to quantify social relationships based on in-person, rather than self-reported, social interactions. We used GPS-derived in-camp and out-of-camp proximity data to analyse how in-person proximity is related to Hair Cortisol Concentration (HCC) among Hadza hunter-gatherers. Time spent in close proximity to other camp members was associated with higher HCC, especially in women. In contrast, individuals who spent more time in close out-of-camp proximity to their best friend experienced lower HCC. Our study suggests that physiological costs related to group living might be mitigated by in-person interactions with close friends. We also find that the location (i.e., in-camp vs out-of-camp) of proximity to others and self-perceived friends is associated with HCC among the Hadza.

The Long-Term Efficacy of "Social Buffering" in Artificial Social Agents: Contextual Affective Perception Matters

In dynamic (social) environments, an affective state of "stress" can be adaptive and promote agent wellbeing, but maladaptive if not appropriately regulated. The presence of (and interactions with) affect-based social support has been hypothesised to provide mechanisms to regulate stress (the "social buffering" hypothesis), though the precise, underlying mechanisms are still unclear. However, the hormone oxytocin has been implicated in mediating these effects in at least two ways: by improving social appraisals and reducing the short-term release of stress hormones (i.e., cortisol), and adapting an agent's long-term stress tolerance. These effects likely facilitate an agent's long-term adaptive ability by grounding their physiological and behavioural adaptation in the (affective) social environment, though these effects also appear to be context-dependent. In this paper, we investigate whether two of the hypothesised hormonal mechanisms that underpin the "social buffering" phenomenon affect the long-term wellbeing of (artificial) social agents who share affective social bonds, across numerous social and physical environmental contexts. Building on previous findings, we hypothesise that "social buffering" effects can improve the long-term wellbeing of agents who share affective social bonds in dynamic environments, through regular prosocial interactions with social bond partners. We model some of the effects associated with oxytocin and cortisol that underpin these hypothesised mechanisms in our biologically-inspired, socially-adaptive agent model, and conduct our investigation in a small society of artificial agents whose goal is to survive in challenging environments. Our results find that, while stress can be adaptive and regulated through affective social support, long-term behavioural and physiological adaptation is determined by the contextual perception of affective social bonds, which is influenced by early-stage interactions between affective social bond partners as well as the degree of the physical and social challenges. We also show how these low-level effects associated with oxytocin and cortisol can be used as "biomarkers" of social support and environmental stress. For socially-situated artificial agents, we suggest that these "social buffering" mechanisms can adapt the (adaptive) stress mechanisms, but that the long-term efficacy of this adaptation is related to the temporal dynamics of social interactions and the contextual perception of the affective social and physical environments.

Oxytocin modulation in the medial prefrontal cortex of pair-exposed rats during fear conditioning

INTRODUCTION

Social buffering is the phenomenon, in which stress and fear reactions caused by exposure to stressful stimuli when animals are exposed to homogeneous relationships are attenuated. Social buffering reduces fear memory behavior such as escape, avoidance, and freezing behavior in rodents due to social existence. Here, we aimed to determine alterations of fear behavior and neural activity in the medial prefrontal cortex (mPFC) in response to the presence of another rat in fear-exposed conditions and to confirm the role of oxytocin in mPFC in regulating social buffering.

METHODS

We performed a passive avoidance test and determined positive c-Fos expression in single- and pair-exposed rats. Anisomycin (a protein synthesis inhibitor) and oxytocin receptor regulators (carbetocin; agonist and atosiban; antagonist) were microinjected into the mPFC to clarify the role of oxytocin in the mPFC.

RESULTS

While single-exposed rats showed a significant increase in both freezing and passive avoidance behaviors compared to control rats, pair-exposed rats showed significantly less fear behavior compared to single-exposed rats. The c-Fos expression in the prelimbic (PL) mPFC was significantly increased in pair-exposed rats compared to that in control and single-exposed rats. The pair-exposed effect was blocked by anisomycin injections into the PL mPFC of pair-exposed rats. Furthermore, when a carbetocin was injected into the PL mPFC in single-exposed rats, fear behavior was decreased, and these changes were blocked by atosiban.

DISCUSSION

Our findings suggest that reduction of fear-related behavior induced by acute pair-exposure is mediated by oxytocin receptors in the PL mPFC. Pair exposure with conspecifics during fear-inducing situations helps coping with fear by significantly increasing the role of oxytocin in the PL mPFC.

Adolescent Peers and Prevention: Network Patterns of Sexual Violence Attitudes and Bystander Actions

Peer sexual violence is a significant social problem that affects adolescents and can lead to negative mental health and developmental consequences. Peers are a significant source of influence for adolescent behavior. For example, recent studies show training teens to be bystanders can be an effective prevention strategy to reduce peer violence and harassment. Peers can also promote risky behaviors including substance use and violence. The current study examined how sexual violence-specific risk and protective attitudes (e.g., denial of peer sexual violence and positive peer prevention norms) and behaviors (alcohol use and bystander actions to prevent peer sexual violence) clustered within peer networks cross-sectionally and over time. Participants were 1,499 7th-10th graders who took surveys during an academic year and who reported having opportunity to take action as bystanders to peer sexual violence. Participants took surveys 6 months apart online in schools. Questions included nomination of best friends to capture information about peer networks. Social network analyses indicated that there was weak but significant clustering of positive prevention attitudes such as bystander denial and marginal clustering on reactive bystander behaviors to address sexual assault. For comparison, alcohol use and academic grades were analyzed and found to also cluster in networks in these data. These findings suggest that for early adolescents, peer bystander training may be influential for some key bystander attitudes and reactive sexual violence prevention behaviors as individual behaviors are not independent of those of their friends.

Diurnal Cortisol in Left-Behind Adolescents: Relations to Negative Family Expressiveness and Internalizing Problems

Despite the accumulating evidence for increased risks for behavioral problems in left-behind adolescents in China, little research has explored their HPA axis functioning, which is hypothesized to play a central role in the association between early adversity and health. In the present study, we designed a longitudinal study to examine HPA axis function in left-behind adolescents and its mediating role in the association between family emotional expressiveness and internalizing problems. Participants were 81 adolescents (44 female; 37 male) aged 11-16 years. Salivary cortisol samples were collected six times a day for two consecutive days on regular school days. Negative family expressiveness (NFE) and internalizing problems were measured using self-report questionnaires. The results showed that NFE was negatively associated with diurnal cortisol, and diurnal cortisol was negatively associated with internalizing problems. Further analysis showed that diurnal cortisol secretion measured by AUC (area under the curve) mediated the association between NFE and internalizing problems. Our findings extended the existing literature about left-behind children via a psychoneuroendocrinological perspective, documenting the negative consequences of the family environment for youth health and development.

Parents' Maltreatment Histories, Dimensions of Emotion Regulation, and Connections to Offspring Self-Regulation: A Sex-Specific Transmission Pathway

Introduction

Parents with childhood maltreatment histories are at risk for emotion regulation (ER) problems, which are associated with reduced self-regulation among their offspring. However, gaps remain in the literature regarding this indirect transmission pathway. First, ER consists of multiple dimensions and it is unclear which dimension is most affected by childhood maltreatment. Second, less is known regarding which parental ER dimension is linked to offspring self-regulation. Thus, the present study aimed to examine the direct and indirect associations between parental maltreatment histories and child self-regulatory capacity via dimensions of parental ER.

Methods

In this cross-sectional study, 101 youth (75% African American/Black; 53% female; M _age = 10.28; SD = 1.19) and their primary caregivers were recruited from a low-income community in the Southeastern United States. Structural equation modeling was used to model the effect of parents' self-reported childhood maltreatment on youth physiological self-regulation (measured by heart rate variability reactivity [HRV-R]), via parents' self-reported ER.

Results

Parental maltreatment history was significantly associated with five of the six components of ER. Further, the indirect effect of parents' childhood maltreatment on child HRV-R was significant when parents reported more difficulty engaging goal-directed behaviors. Moderation analyses by sex showed that daughters had greater dysregulation regardless of parental maltreatment histories, while parents' ER was found to play a more significant role in the intergenerational transmission of dysregulation to sons.

Conclusions

The current study extends the literature on self-regulation development in children of low-income, maltreatment-exposed parents. Our study may inform parent-child interventions for improving self-regulation.

Social Regulation of Negative Valence Systems During Development

The ability to sense, perceive, and respond appropriately to aversive cues is critical for survival. Conversely, dysfunction in any of these pathway components can lead to heightened avoidance of neutral or rewarding cues, such as social partners. The underlying circuitry mediating both negative valence processing and social behavior is particularly sensitive to early life experience, but mechanisms linking experience to pathology remain elusive. Previous research in humans, rodents, and non-human primates has highlighted the unique neurobiology of the developing infant and the role of the caregiver in mediating the infant’s negative valence circuitry, and the importance of this early social relationship for scaffolding lasting social behavior. In this review, we summarize the current literature on the development of negative valence circuits in the infant and their social regulation by the caregiver following both typical and adversity-rearing. We focus on clinically-relevant research using infant rodents which highlights the amygdala and its interface with the mesolimbic dopamine system through innervation from the ventral tegmental area (VTA) as a locus of dysfunction following early-life adversity. We then describe how these circuits are recruited to perturb life-long social behavior following adversity and propose additional therapeutic targets in these circuits with an eye toward developing age-appropriate interventions.

Perceived stress and rejection associated with functional network strength during memory retrieval in adolescents

The brain undergoes substantial structural and functional remodeling during adolescence, including alterations in memory-processing regions influenced by stress. This study evaluated brain activation using functional magnetic resonance imaging (fMRI) during spatial memory performance using a virtual Morris water task (MWT) and examined the associations between default mode network (DMN) activation, task performance, and perceived stress and rejection. Functional magnetic resonance imaging data were acquired at 3 Tesla from 59 (34 female) adolescents (13-14 years). The NIH Emotion Toolbox was used to measure perceived stress and rejection. During the MWT, hippocampus and prefrontal cortex showed greater activation during memory retrieval relative to motor performance. Templates of brain functional networks from the Human Connectome Project study were used to extract individual participants' brain network activation strengths for the retrieval > motor contrast for two sub-networks of the default mode network: medial temporal lobe (MTL-DMN) and dorsomedial prefrontal (dMPFC-DMN). For the MTL-DMN sub-network only, activation was significantly associated with worse MWT performance (p = .008) and greater perceived stress (p = .008) and perceived rejection (p = .002). Further, MWT performance was negatively associated with perceived rejection (p = .007). These findings suggest that perceived stress and rejection are related to engagement of MTL-DMN during spatial memory and that engagement of this network impacts performance. These findings also demonstrate the utility of examining task-related network activation strength to identify the impact of perceived stress and rejection on large-scale brain network functioning during adolescence.

The Transdiagnostic Origins of Anxiety and Depression During the Pediatric Period: Linking NIMH Research Domain Criteria (RDoC) Constructs to Ecological Systems

In the last decade, an abundance of research has utilized the NIMH Research Domain Criteria (RDoC) framework to examine mechanisms underlying anxiety and depression in youth. However, relatively little work has examined how these mechanistic intrapersonal processes intersect with context during childhood and adolescence. The current paper covers reviews and meta-analyses that have linked RDoC-relevant constructs to ecological systems in internalizing problems in youth. Specifically, cognitive, biological, and affective factors within the RDoC framework were examined. Based on these reviews and some of the original empirical research they cover, we highlight the integral role of ecological factors to the RDoC framework in predicting onset and maintenance of internalizing problems in youth. Specific recommendations are provided for researchers using the RDoC framework to inform future research integrating ecological systems and development. We advocate for future research and research funding to focus on better integration of the environment and development into the RDoC framework.

Systematic Input-Output Mapping Reveals Structural Plasticity of VTA Dopamine Neurons-Zona Incerta Loop Underlying the Social Buffering Effects in Learned Helplessness

A common phenomenon called social buffering (SB), communication within conspecific animals is a benefit for a stressed individual to better recover from aversive events, is crucial to all mammals. Although the dopamine reward system has been implicated in SB, it is not clear which neuronal populations are relevant and how they contribute. Here, we adopted a learned helplessness (LH) animal model of depression and found that LH subjects housed with a conspecific partner show better performance in the shuttle box test, showing that SB improves the stress-coping abilities to deal with stress. Bidirectional manipulation of ventral tegmental area (VTA) dopamine neurons by chemogenetic tools can mimic or block the SB effect in LH mice. To screen for SB-induced structure plasticity of VTA dopamine neurons, we employed viral genetic tools for mapping input and output architecture and found LH- and SB-triggered circuit-level changes in neuronal ensembles. Zona incerta (ZI), an overlapping brain region, was significantly changed in both anterograde and retrograde tracing during LH and SB. These results reveal a neural loop with structural plasticity between VTA dopamine neurons and ZI underlies the SB effects in LH and lays a foundation for studying how VTA dopamine neurons regulate SB-related neural circuits.

Linking post-stressor interpersonal processes in adolescent girls' close friendships with acute HPA stress responses

INTRODUCTION

For adolescent girls, close friendships may facilitate stress management and mitigate risk for internalizing psychopathology. However, little is known about how friendship processes may buffer (or potentially exacerbate) acute psychobiological responses to interpersonal stressors in ways that affect risk.

METHODS

In a sample of 220 girls (ages 12-17 years) with a history of internalizing symptoms, this study investigated friendship dynamics following the Trier Social Stress Test (TSST) to evaluate associations between post-stressor friendship behaviors (expressions of vulnerability by the stressed teen; support offered by their close friend) and hypothalamic-pituitary-adrenal (HPA) axis stress responses.

RESULTS

Multilevel regression modeling revealed that girls who displayed more pronounced cortisol reactivity expressed greater vulnerability to, and received greater support from, their close friend. Expressed vulnerability was associated with more efficient cortisol recovery. Close friend support was not significantly associated with cortisol recovery, nor did it influence the connection between expressed vulnerability and cortisol recovery.

CONCLUSIONS

Findings suggest that HPA reactivity may prompt expressions of vulnerability to girls' close friends, and in this context, promote more efficient HPA recovery. Findings highlight the role friendship dynamics may play in HPA-related risk for internalizing symptoms and point to expressed vulnerability in adolescent girls' close friendships as a potential consideration for interpersonally-centered therapeutic approaches.

Environmental determinants of physiological reactivity to stress: The interacting effects of early life deprivation, caregiving quality, and stressful life events

Children who spend their early lives in institutions experience profound psychosocial deprivation that is associated with altered stress response system development. Here, we used data from a longitudinal randomized controlled trial of foster care for institutionally reared children to examine whether caregiving quality and stressful life events (SLEs) in early adolescence (age 12) influence patterns of hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS) reactivity. Controlling for the effect of institutional care, higher caregiving quality at age 12 was associated with heightened cortisol and SNS reactivity. However, moderation analysis revealed that the latter effect was only observed among never-institutionalized children, whereas ever-institutionalized children demonstrated a persistently blunted SNS response regardless of recent caregiving quality. Among institutionally reared children, SLEs interacted with prior random assignment to foster care, such that those placed in foster care early in development had a SNS response that approximated never-institutionalized children when SLEs at age 12 were low. In contrast, SNS reactivity was persistently blunted among those with prolonged deprivation, regardless of recent SLEs. Early-life deprivation is associated with persistent blunting of stress response systems, but normalization may be achievable if SLEs are limited following placement into enriched family-based care.

Maternal Depression and Mother-Child Oxytocin Synchrony in Youth with Anxiety Disorders

The neuropeptide oxytocin (OT) plays a central role in the regulation of affiliative bonds and anxiety. However, the degree to which its levels are synchronized between interaction partners has not yet been assessed. Physiological synchrony assessed using other peripheral measures (e.g., heart rate, etc.) has been tied to positive outcomes for the individual and the dyad. The present study examined OT synchrony in the context of child anxiety and maternal depression by examining mother-child dyads. Mothers and their children with anxiety disorders participated in a behavioral interaction task. Changes in OT levels and mother-child OT synchrony before and after the interaction, as well as their moderation by maternal depression, were assessed. Ninety-eight youth with anxiety disorders (ages 10 to 17) and their mothers underwent psychiatric evaluation, and mothers rated their own depressive symptoms and their children's behavior problems. Salivary OT was assayed from mother and child before and after the task. Behavioral coding showed that interactions were characterized by high behavioral synchrony between mothers and their children, and both individuals displayed higher levels of positive vs. negative affect during the interactions. Mothers and their children also showed decreases in OT levels after the interaction. As hypothesized, OT synchrony increased following the task, but only dyads in which mothers showed high levels of depressive symptoms showed this increase. As hypothesized, lower levels of OT-synchrony were associated with higher levels of child internalizing symptoms. The findings suggest that positive interactions may be beneficial for youth with anxiety disorders with mothers with depression.

Oxytocin Pathway Gene (CD38, OXTR) Variants Are Not Related to Psychosocial Characteristics Defined by Strengths and Difficulties Questionnaire in Adolescents: A Field School-Based Study

Background: CD38 is a transmembrane glycoprotein that regulates oxytocin (OT) production and influences social interactions. The oxytocin receptor (OXTR) has been studied intensively regarding its association with human psychosocial functions. Many studies have demonstrated a link between CD38 rs3796863 and OXTR rs53576 polymorphic regions and psychosocial characteristics as well as various psychiatric disorders in adolescents. Some studies, however, have reported null findings. Methods: The Strengths and Difficulties Questionnaire (SDQ) is a brief psychopathologic screening tool recommended for detecting psychosocial problems and psychiatric disorders in adolescents. The current field school-based study, conducted among urban Siberian adolescents (n = 298 aged 12-18), explored the SDQ scales in relation to polymorphisms of the CD38 and the OXTR genes (rs3796863 and rs53576, respectively). Results: None of the studied genotypes were associated with the SDQ results for the complete sample with presumed statistical power as 0.80 to detect a medium-size effect (Cramer's V = 0.3) at α = 0.0083. Post-hoc analysis in subgroups showed that OT pathway high activity may cause some negative consequences, such as emotional instability in older (aged 15-18) adolescent boys who are carriers of the rs53576 GG variant. Conclusion: Variations at the CD38 rs3796863 and OXTR rs53576 loci were not associated with psychosocial characteristics of adolescents assessed with the SDQ. In studies with a similar design, we recommend replication with larger samples and greater power to detect small effects, especially in age-sex subgroups of adolescents.

Revisit the Effectiveness of Educational Kinesiology on Stress and Anxiety Amelioration in Kindergarteners With Special Needs Using Biological Measures

Background: Educational kinesiology is a popular intervention that aims to improve brain functioning via physical movements. Yet, it lacks supporting scientific evidence and is regarded as pseudoscience. Given the popularity of educational kinesiology in school settings, it is important to revisit its effectiveness through scientific research. Previous studies that evaluated the effectiveness of educational kinesiology relied mainly on subjective measures, in which subjective bias is inevitable. Cortisol and oxytocin levels in saliva have been reported to be reliable stress and anxiety markers that provide unbiased objective data. This study explores the effect of educational kinesiology on the changes in salivary cortisol and oxytocin levels in kindergarteners with special needs. Methods: A quasi-experimental design was adopted in this study. Thirty-seven kindergarteners (3.5-6.5 years old) who were either diagnosed with one type of special needs or referred by school principals due to the requirement of special supports at school were assigned to either the intervention group, which received 1-h educational kinesiology intervention weekly for a total of 10 weeks, or the wait-list control group. Saliva samples were collected at baseline and after the completion of intervention programme for the measurement of cortisol and oxytocin levels. Scores of Parent-rated Preschool Anxiety Scale (PAS-TC) were also collected at pre- and post-intervention. Because of the small samples, non-parametric tests such as Mann-Whitney U test, Quade test, and Fisher's exact tests were used in this study where appropriate. Results: After controlled for the effect at baseline, gender and types of special needs, the changes in oxytocin levels were significantly higher in the intervention group compared with control [F _{(1, 35)} = 4.747, p = 0.036, eta² = 0.119], whereas no significant between-group difference in changes of cortisol levels was observed [F _{(1, 35)} = 0.306, p = 0.584, eta² = 0.009]. Results from PAS-TC showed significant improvement in anxiety levels after the intervention in the intervention group (p = 0.048, ϕ = 0.344, p = 0.037). Conclusions: Our findings suggest a plausible anti-anxiety effect of educational kinesiology in kindergarteners with special needs by elevating the oxytocin levels. Future studies are warranted to further confirm our findings with a larger sample.

Differential brain activity as a function of social evaluative stress in early adolescence: Brain function and salivary cortisol

Understanding individual differences in neural responses to stressful environments is an important avenue of research throughout development. These differences may be especially critical during adolescence, which is characterized by opportunities for healthy development and increased susceptibility to the development of psychopathology. While the neural correlates of the psychosocial stress response have been investigated in adults, these links have not been explored during development. Using a new task, the Minnesota Imaging Stress Test in Children (MISTiC), differences in activation are found in fusiform gyrus, superior frontal gyrus, insula, and anterior cingulate cortex when comparing a stressful math task to a nonstressful math task. The MISTiC task successfully elicits cortisol responses in a similar proportion of adolescents as in behavioral studies while collecting brain imaging data. Cortisol responders and nonresponders did not differ in their perceived stress level or behavioral performance during the task despite differences in neuroendocrine function. Future research will be able to leverage the MISTiC task for many purposes, including probing associations between individual differences in stress responses with environmental conditions, personality differences, and the development of psychopathology.

Neurobiological Markers of Resilience to Early-Life Adversity During Adolescence

Early-life adversity (ELA) exposure (e.g., trauma, abuse, neglect, or institutional care) is a precursor to poor physical and mental health outcomes and is implicated in 30% of adult mental illness. In recent decades, ELA research has increasingly focused on characterizing factors that confer resilience to ELA and on identifying opportunities for intervention. In this review, we describe recent behavioral and neurobiological resilience work that suggests that adolescence (a period marked by heightened plasticity, development of key neurobiological circuitry, and sensitivity to the social environment) may be a particularly opportune moment for ELA intervention. We review intrapersonal factors associated with resilience that become increasingly important during adolescence (specifically, reward processing, affective learning, and self-regulation) and describe the contextual factors (family, peers, and broader social environment) that modulate them. In addition, we describe how the onset of puberty interacts with each of these factors, and we explore recent findings that point to possible "pubertal recalibration" of ELA exposure as an opportunity for intervention. We conclude by describing considerations and future directions for resilience research in adolescents, with a focus on understanding developmental trajectories using dimensional and holistic models of resilience.

[Oxitocin is a hormone of trust and emotional attachment: the influence on behavior of children and adolescents]

This review presents current data on the mechanisms of production and reception of oxytocin and its effect on the socio-emotional aspects of behavior in different age periods of childhood and adolescence. The main hormonal role of oxytocin is to regulate the process of carrying a fetus, childbirth and lactation, as well as the establishment of social connections from the infancy period (connection with parents with a child) throughout childhood to adolescence and adult periods of life. Its central action takes the most important part in cognitive, emotional and behavioral processes. In addition, oxytocin plays a role in the regulation of food and sexual behavior, in the mechanisms of visceral hypersensitivity and pain perception. The analysis of publications covering the most important role of oxytocin in the formation of the emotional interaction between parents and children in different age periods: infancy, preschool and adolescence was carried out. A brief analysis of genetically determined features of the production and reception of oxytocin and their role in the regulation of behavioral responses is presented. In addition, the review briefly highlights aspects of the likely involvement of oxytocin in the mechanisms of formation of certain psychopathological conditions in children and adolescents.

Modelling resilience in adolescence and adversity: a novel framework to inform research and practice

Recent conceptualisations of resilience have advanced the notion that it is a dynamic and multifaceted construct. However, its adaptive components, especially those forged by adversity, have not been fully realised, and its neurobiological and psychosocial underpinnings are yet to be meaningfully integrated. In part, this is because a developmental perspective is often neglected in the formulation of resilience. In this review, we consider the findings of resilience research, with a specific emphasis on the developmental period of adolescence. To bridge the gaps in our current understanding, we propose a model of resilience that is predicated on experiencing adversity. Specifically, our model provides a sophisticated insight into the components of resilience, which, together with intrinsic features, involves facilitation of, and skill acquisition via strengthening processes we term tempering and fortification. The model also points to the potential trajectories of adversity-driven resilience and forms the basis of a framework that allows for individual variance in resilience, and the identification of both neurobiological and psychosocial targets for prevention and therapeutic interventions.

Understanding the Neurobiological Implications of Maltreatment: A Commentary on the Special Issue

A large body of evidence demonstrates the deleterious effects of childhood maltreatment that span across multiple levels of functioning and throughout development. This commentary highlights the important research in this special issue of Child Maltreatment that advances our understanding of the neural and physiological implications of maltreatment. Throughout, the commentary calls attention to critical issues in the study of maltreatment and neurobiological processes for future work in this area.

Adrenocortical and autonomic attunement between romantic partners in emerging adulthood

Parent-child physiological attunement, particularly during stressful situations, appears adaptive as shared stress reactivity may promote dyadic engagement. Romantic partners eventually replace parents as the primary support figure, yet it remains unclear whether romantic partners buffer physiological stress or display physiological attunement as most studies on adults examine attunement during conflict paradigms. The present study examined physiological attunement in 63 emerging adult romantic partner dyads (one partner was the active participant, the other the observer) during the Trier Social Stress Task (TSST). Heart rate (HR) and respiratory sinus arrhythmia (RSA) were continuously monitored across the visit. Repeated saliva samples were assayed for cortisol. Physiological attunement was operationalized as a correlation in biomarkers between the TSST participant and their partner; sex, social support, and physical proximity were examined as moderators. We then compared the biomarker profiles of partnered-TSST participants to individuals who participated in the TSST solo (n = 63) to determine if partner presence buffered stress biomarker reactivity during the TSST. RSA attunement between partners was found but was not further moderated by social support or sex. Adrenocortical attunement was moderated, such that lower social support and increased proximity resulted in higher attunement. HR attunement was higher when the participant was male and when partners were in close physical proximity. Compared to TSST solo, romantic partner presence increased participant cortisol levels and altered HR reactivity, suggesting that emerging adult romantic partners do not buffer physiological stress reactivity. Future research should examine whether physiological attunement and partner presence is protective in more established relationships.

Neurobiology of maternal regulation of infant fear: the role of mesolimbic dopamine and its disruption by maltreatment

Child development research highlights caregiver regulation of infant physiology and behavior as a key feature of early life attachment, although mechanisms for maternal control of infant neural circuits remain elusive. Here we explored the neurobiology of maternal regulation of infant fear using neural network and molecular levels of analysis in a rodent model. Previous research has shown maternal suppression of amygdala-dependent fear learning during a sensitive period. Here we characterize changes in neural networks engaged during maternal regulation and the transition to infant self-regulation. Metabolic mapping of 2-deoxyglucose uptake during odor-shock conditioning in postnatal day (PN)14 rat pups showed that maternal presence blocked fear learning, disengaged mesolimbic circuitry, basolateral amygdala (BLA), and plasticity-related AMPA receptor subunit trafficking. At PN18, when maternal presence only socially buffers threat learning (similar to social modulation in adults), maternal presence failed to disengage the mesolimbic dopaminergic system, and failed to disengage both the BLA and plasticity-related AMPA receptor subunit trafficking. Further, maternal presence failed to block threat learning at PN14 pups following abuse, and mesolimbic dopamine engagement and AMPA were not significantly altered by maternal presence-analogous to compromised maternal regulation of children in abusive relationships. Our results highlight three key features of maternal regulation: (1) maternal presence blocks fear learning and amygdala plasticity through age-dependent suppression of amygdala AMPA receptor subunit trafficking, (2) maternal presence suppresses engagement of brain regions within the mesolimbic dopamine circuit, and (3) early-life abuse compromises network and molecular biomarkers of maternal regulation, suggesting reduced social scaffolding of the brain.

Hunting for What Works: Adolescents in Addiction Treatment

Although adolescents are developmentally distinct from adults, they often receive addiction treatment based on adult models. This is problematic because adolescents face significantly different conditions in addiction treatment, including distinct basic biological and neurodevelopmental stages, unique sociodevelopmental concerns, distinctive addiction trajectories, and, in turn, disparate treatment goals and outcomes. In sum, it can be difficult for even savvy clinicians to know how to approach addiction treatment with this important age group. In an effort to help clinicians and researchers consider substance use via a neurodevelopmental lens, we approached this review with 4 goals: (i) characterize the prevalence, and related health and safety implications of substance use within this age group; (ii) identify the nature of the adolescent brain, including characteristic features of this phase of neurodevelopment relevant to adolescent substance use treatment; (iii) provide an overview of current adolescent addiction interventions and avenues to improve clinical treatment and clinical research efforts for adolescents; and (iv) examine the intersection between the nature of the developing brain and adolescent substance use, and utilize that information to inform alternative routes and directions for substance use treatment in this critical age group. This review concludes by offering a novel neurodevelopmental model and framework to examine substance use interventions, along with a series of recommendations to optimize adolescent substance use treatment and clinical research.

Dyadic Coping and Its Underlying Neuroendocrine Mechanisms - Implications for Stress Regulation

Previous research suggests that neuroendocrine mechanisms underlie inter-individual stress coping in couples. The neuropeptide oxytocin (OT), while regulating stress-sensitive HPA-axis activity might be crucial in this process. The purpose of this study was to examine the impact of dyadic coping abilities and OT on HPA-axis outcomes and constructive behavior during couple conflict. We conducted a secondary analysis of our previous database (Ditzen et al., 2009), assessing the modulating role of dyadic coping and intranasal OT on couple conflict behavior. The data revealed a significant interaction effect of the dyadic coping by oneself score and OT on cortisol responses during couple conflict, suggesting that particularly individuals with low a priori dyadic coping benefit from OT in terms of dampened HPA-activity. The results are in line with previous research suggesting OT’s central role for stress regulation and prosocial behavior. Furthermore, an interaction with dyadic coping indicates adaptations in the sensitivity of the OT system during the individual attachment and relationship history. These data add to the evidence that the neuroendocrine attachment systems influence couple behavior. Future studies of neurobiological mechanisms underlying dyadic coping will be of high relevance for the development of prevention and intervention programs.

The role of bicultural adaptation, familism, and family conflict in Mexican American adolescents' cortisol reactivity

Scarce research has examined stress responsivity among Latino youths, and no studies have focused on the role of acculturation in shaping cortisol stress response in this population. This study assessed Mexican American adolescents' Mexican and Anglo cultural orientations and examined prospective associations between their patterns of bicultural orientation and hypothalamic-pituitary-adrenal cortisol reactivity to an adapted Trier Social Stress Test. The sample included 264 youths from a longitudinal birth cohort study who completed the Trier Social Stress Test and provided saliva samples at age 14. The youths completed assessments of cultural orientation at age 12, and family conflict and familism at age 14. Analyses testing the interactive effects of Anglo and Mexican orientation showed significant associations with cortisol responsivity, including the reactivity slope, peak levels, and recovery, but these associations were not mediated by family conflict nor familism values. Findings revealed that bicultural youth (high on both Anglo and Mexican orientations) showed an expected pattern of high cortisol responsivity, which may be adaptive in the context of a strong acute stressor, whereas individuals endorsing only high levels of Anglo orientation had a blunted cortisol response. Findings are discussed in relation to research on biculturalism and the trade-offs and potential recalibration of a contextually responsive hypothalamic-pituitary-adrenal axis for acculturating adolescents.

How do hypothalamic nonapeptides shape youth's sociality? A systematic review on oxytocin, vasopressin and human socio-emotional development

The hypothalamic nonapeptides oxytocin and vasopressin are important modulators of socio-affective behaviours in a wide variety of animal species, including humans. Nevertheless, there is little research addressing their possible roles on socio-affective dimensions of human behaviour across development, during which considerable behavioural and physiological change occurs. Questions still remain about the extent to which findings from adults may directly apply to earlier phases of human development. In this article, we systematically summarize and discuss all existing studies investigating the developmental association of endogenous levels of hypothalamic neuropeptides oxytocin and vasopressin with human social behaviour or on its disruption in paediatric populations. Evidence is sparse insofar as there are still relatively few developmental studies and limited due to correlational research designs and unreliability of methods currently used for neuropeptide measurements in biological fluids. The findings to date generally converge with adult evidence, but also suggest that important differences between age stages may exist. Further studies focusing these differences may prove critical for informing drug development for socio-affective deficits in paediatric populations.

Annual Research Review: Early adversity, the hypothalamic-pituitary-adrenocortical axis, and child psychopathology

BACKGROUND

Research on early adversity, stress biology, and child development has grown exponentially in recent years.

FINDINGS

We review the current evidence for the hypothalamic-pituitary-adrenocortical (HPA) axis as a stress-mediating mechanism between various forms of childhood adversity and psychopathology. We begin with a review of the neurobiology of the axis and evidence for relations between early adversity-HPA axis activity and HPA axis activity-psychopathology, as well as discuss the role of regulatory mechanisms and sensitive periods in development.

CONCLUSIONS

We call attention to critical gaps in the literature to highlight next steps in this research including focus on developmental timing, sex differences, stress buffering, and epigenetic regulation. A better understanding of individual differences in the adversity-HPA axis-psychopathology associations will require continued work addressing how multiple biological and behavioral systems work in concert to shape development.

Comparative studies of social buffering: A consideration of approaches, terminology, and pitfalls

KIYOKAWA, Y. and HENNESSY, M.B. Comparative studies of social buffering: A consideration of approaches, terminology, and pitfalls…NEUROSCI BIOBEHAV REV XXX-XXX, .- Over the past decades, there has been an increasing number of investigations of the impact of social variables on neural, endocrine, and immune outcomes. Among these are studies of "social buffering"-or the phenomenon by which affiliative social partners mitigate the response to stressors. Yet, as social buffering studies have become more commonplace, the variety of approaches taken, definitions employed, and divergent results obtained in different species can lead to confusion and miscommunication. The aim of the present paper, therefore, is to address terminology and approaches and to highlight potential pitfalls to the study of social buffering across nonhuman species. We review and categorize variables currently being employed in social buffering studies and provide an overview of responses measured, mediating sensory modalities and underlying mechanisms. It is our hope that the paper will be useful to those contemplating examination of social buffering in the context of their own research.

The role of trauma in the hormonal interplay of cortisol, testosterone, and oxytocin in adolescent aggression

Although numerous studies have examined the neuroendocrinology of aggression, the findings are mixed and focused on cortisol and testosterone. We argue that past findings remain inconclusive partly because the key roles of oxytocin and trauma have not been systematically integrated yet. Oxytocin is associated with social behavior and interacts with cortisol and testosterone, whereas trauma is a crucial risk factor of aggression that strongly affects hormonal activity. In this review, we investigate the role of trauma in the hormonal interplay of cortisol, testosterone, and oxytocin in aggression during adolescence. We first discuss how these hormones interact with each other and how trauma influences these interactions and then we propose a model that highlights the role of trauma in the hormonal interplay in aggression. We suggest that the timing of trauma has a distinct effect on hormonal activity and it should be integrated into any comprehensive model. Current trauma is linked to different levels of oxytocin, cortisol, testosterone, and testosterone/cortisol ratio than childhood trauma, but this distinction is also influenced by gender and type of aggression. We conclude that in order to better understand the neuroendocrinology of aggression, it is crucial to incorporate the investigation of oxytocin and trauma in future research.

Social Buffering of Stress in Development: A Career Perspective

This review provides a broad overview of my research group's work on social buffering in human development in the context of the field. Much of the focus is on social buffering of the hypothalamic-pituitary-adrenocortical (HPA) system, one of the two major arms of the mammalian stress system. This focus reflects the centrality of the HPA system in research on social buffering in the fields of developmental psychobiology and developmental science. However, buffering of the cardiovascular and autonomic nervous system is also discussed. The central developmental question in this area derives from attachment theory, which argues that the infant's experience of stress and arousal regulation in the context of her early attachment relationships is not an immature form of social buffering experienced in adulthood but rather the foundation out of which individual differences in the capacity to gain stress relief from social partners emerges. The emergence of social buffering in infancy, changes in social buffering throughout childhood and adolescence, the influence of early experience on later individual differences in social buffering, and critical gaps in our knowledge are described.

From attachment to independence: Stress hormone control of ecologically relevant emergence of infants' responses to threat

Young infant rat pups learn to approach cues associated with pain rather than learning amygdala-dependent fear. This approach response is considered caregiver-seeking and ecologically relevant within the context of attachment. With maturation, increases in the stress hormone corticosterone permit amygdala-dependent fear, which is crucial for survival during independent living. During the developmental transition from attachment to fear learning, maternal presence suppresses corticosterone elevation to block amygdala-dependent fear learning and re-engage the attachment circuitry. Early life trauma disrupts this developmental sequence by triggering a precocious increase of corticosterone, which permits amygdala-dependent threat responses. In this review, we explore the importance of the stress hormone corticosterone in infants' transition from complete dependence on the caregiver to independence, with consideration for environmental influences on threat response ontogeny and mechanistic importance of social buffering of the stress response.

Neurodevelopmental changes across adolescence in viewing and labeling dynamic peer emotions

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Dynamic peer facial stimuli recruit key regions involved in emotion processing.

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LPFC shows a nonlinear age trend across adolescence to labeling dynamic peer faces.

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MOFC/vMPFC shows a linear decrease with age to viewing dynamic peer faces.

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No significant age trends were observed in amygdala during viewing or labeling dynamic peer faces.

Adolescence is a sensitive period of social-affective development, characterized by biological, neurological, and social changes. The field currently conceptualizes these changes in terms of an imbalance between systems supporting reactivity and regulation, specifically nonlinear changes in reactivity networks and linear changes in regulatory networks. Previous research suggests that the labeling or reappraisal of emotion increases activity in lateral prefrontal cortex (LPFC), and decreases activity in amygdala relative to passive viewing of affective stimuli. However, past work in this area has relied heavily on paradigms using static, adult faces, as well as explicit regulation. In the current study, we assessed cross-sectional trends in neural responses to viewing and labeling dynamic peer emotional expressions in adolescent girls 10–23 years old. Our dynamic adolescent stimuli set reliably and robustly recruited key brain regions involved in emotion reactivity (medial orbital frontal cortex/ventral medial prefrontal cortex; MOFC/vMPFC, bilateral amygdala) and regulation (bilateral dorsal and ventral LPFC). However, contrary to the age-trends predicted by the dominant models in studies of risk/reward, the LPFC showed a nonlinear age trend across adolescence to labeling dynamic peer faces, whereas the MOFC/vMPFC showed a linear decrease with age to viewing dynamic peer faces. There were no significant age trends observed in the amygdala.

Maternal buffering of fear-potentiated startle in children and adolescents with trauma exposure

Parental availability influences fear expression and learning across species, but the effect of maternal buffering on fear learning in humans is unknown. Here we investigated the effect of maternal availability during fear conditioning in a group of children (ages 8-10) and adolescents (ages 11-13) from a low-income population with a range of trauma exposure. Acoustic startle response data were collected to measure fear-potentiated startle (FPS) in 104 participants. A total of 62 participants were tested with the mother available and 42 when the mother was not in the testing room. We observed that maternal availability during fear conditioning interacted with age to affect FPS discrimination between CS+ and CS-. In line with previous findings suggesting an absence of maternal buffering in adolescents, fear discrimination was affected by maternal availability only in children. Second, we observed that the effect of maternal buffering on FPS discrimination in children was not influenced by maternally reported warmth. In conclusion, we demonstrated that maternal availability improved discrimination in children, regardless of the quality of the relationship. Adolescents discriminated irrespective of maternal status, suggesting that childhood may be a sensitive period for environmental influences on key processes such as learning of danger and safety signals.