Stress-induced elevation of oxytocin in maltreated children: evolution, neurodevelopment, and social behavior

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.

Endogenous oxytocin is associated with the experience of compassion and recalled upbringing in Borderline Personality Disorder

BACKGROUND/OBJECTIVE

The role of the neuropeptide oxytocin (OT) in Borderline Personality Disorder (BPD) is poorly understood. It is particularly unknown how early experiences with caregivers moderate the action of OT in BPD. Here, we examined the association of plasma OT levels in BPD patients with the experience of compassion and recalled parental behavior during childhood.

METHODS

Fifty-seven BPD patients and 43 healthy controls participated in the study. OT plasma levels were analyzed by radioimmunoassay. Subjects additionally completed questionnaires focusing on fears of compassion (FOC) and recalled upbringing ("Questionnaire of Recalled Parental Rearing Behavior/Fragebogen zum erinnerten elterlichen Erziehungsverhalten," FEE).

RESULTS

BPD patients had significantly lower OT plasma levels than healthy controls and differed significantly on all FOC and FEE scales; BPD patients had higher FOC scores (indicating more aversion of being compassionate to themselves and others and receiving compassion from others). They also differed in recalled parenting. In the BPD group, scores of the FOC scale "fear of compassion from others" were significantly negatively correlated with OT levels. Moreover, recalled "emotional warmth" of their parents during childhood was positively correlated with OT plasma levels of BPD subjects. No such correlations were found in the control group.

CONCLUSION

Our results corroborate findings from previous studies reporting lower OT levels in patients with BPD. Moreover, peripheral OT seems to be linked with the tolerance of compassionate feelings and early experiences with caregivers. This is consistent with other findings that OT is an important mediator of the experience of emotional warmth from others.

Alterations of brain volumes in women with early life maltreatment and their associations with oxytocin

Early life maltreatment (ELM) is associated with different neurobiological alterations. Lower oxytocin and altered grey matter volumes (GMV) in brain regions associated with the central oxytocin system, such as the hypothalamus, amygdala, and nucleus accumbens, have been reported in women with ELM. However, the association between peripheral oxytocin and brain morphometry in women with ELM has not been studied yet. We therefore collected blood samples from 33 women with and 25 women without ELM, all without current mental disorders to measure and compare oxytocin levels between the two groups. Furthermore, T1-weighted high-resolution structural magnetic resonance brain images of a subsample of these women were collected, analyzed with voxel-based morphometry, compared between the two groups, and correlated with oxytocin levels. There were no differences in oxytocin levels between the groups. However, oxytocin levels were associated with different brain regions in women with ELM compared with control women without ELM: A positive association between GMV in the nucleus accumbens and oxytocin was specific for control women but not for women with ELM. For the hypothalamus, there was a positive association between GMV and oxytocin in control women. However, the same region was negatively associated with oxytocin in women with ELM and it showed larger GMV compared to control women without ELM. For the amygdala, a negative association between GMV and oxytocin was specific for women with ELM. Results are discussed with regard to previous research on endocrine and neurostructural alterations in individuals with ELM.

Early-life adversity and cortisol response to social stress: a meta-analysis

Early-life adversity has been associated with a life-long increased risk for psychopathology and chronic health problems. These long-term negative effects have been explained through stress sensitization, which may involve dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis through either increased or decreased reactivity. The present meta-analysis assessed for the first time the effect of early-life adversity on cortisol response to social stress. Thirty data sets were included in the meta-analysis, in which early-life adversity and salivary cortisol response to social stress were assessed in 4292 individuals of different ages. Results indicated a moderate effect size (g = -0.39) in overall cortisol levels across studies. Separate analyses of cortisol at different stages of response showed large effect sizes at peak and recovery, and a moderate effect at baseline. Heterogeneity was large in this sample of studies and several moderators were identified. The effect size was larger in studies that focused on maltreatment compared to those that included other adversities, and in adults compared to children and adolescents. Percent of women in each sample and methodological quality were positive predictors of the effect size. Publication bias may be present, but the analysis was hampered by the high heterogeneity. Therefore, these results support the association between early-life adversity and blunted cortisol response to social stress, and they suggest that the long-term negative effects of early-life adversity may reach maximum levels in adults.

Perinatal depression and DNA methylation of oxytocin-related genes: a study of mothers and their children

The present study investigated the association of perinatal depression (PD) with differential methylation of 3 genomic regions among mother and child dyads: exon 3 within the oxytocin receptor (OXTR) gene and 2 intergenic regions (IGR) between the oxytocin (OXT) and vasopressin (AVP) genes. Maternal PD was assessed at 5 time-points during pregnancy and postpartum. Four groups were established based on Edinburgh Postnatal Depression Scale (EPDS) cut-off scores: no PD, prenatal or postpartum depressive symptoms only and persistent PD (depressive symptoms both prenatally and postpartum). Salivary DNA was collected from mothers and children at the final time-point, 2.9years postpartum. Mothers with persistent PD had significantly higher overall OXTR methylation than the other groups and this pattern extended to 16/22 individual CpG sites. For the IGR, only the region closer to the AVP gene (AVP IGR) showed significant differential methylation, with the persistent PD group displaying the lowest levels of methylation overall, but not for individual CpG sites. These results suggest that transient episodes of depression may not be associated with OXTR hypermethylation. Validation studies need to confirm the downstream biological effects of AVP IGR hypomethylation as it relates to persistent PD. Differential methylation of the OXTR and IGR regions was not observed among children exposed to maternal PD. The consequences of OXTR hypermethylation and AVP IGR hypomethylation found in mothers with persistent PDS may not only impact the OXT system, but may also compromise maternal behavior, potentially resulting in negative outcomes for the developing child.

The Oxytocin-Vasopressin Pathway in the Context of Love and Fear

Vasopressin (VP) and oxytocin (OT) are distinct molecules; these peptides and their receptors [OT receptor (OTR) and V1a receptor (V1aR)] also are evolved components of an integrated and adaptive system, here described as the OT-VP pathway. The more ancient peptide, VP, and the V1aRs support individual survival and play a role in defensive behaviors, including mobilization and aggression. OT and OTRs have been associated with positive social behaviors and may function as a biological metaphor for social attachment or "love." However, complex behavioral functions, including selective sexual behaviors, social bonds, and parenting require combined activities of OT and VP. The behavioral effects of OT and VP vary depending on perceived emotional context and the history of the individual. Paradoxical or contextual actions of OT also may reflect differential interactions with the OTR and V1aR. Adding to the complexity of this pathway is the fact that OT and VP receptors are variable, across species, individuals, and brain region, and these receptors are capable of being epigenetically tuned. This variation may help to explain experience-related individual and sex differences in behaviors that are regulated by these peptides, including the capacity to form social attachments and the emotional consequences of these attachments.

Oxytocin and Interpersonal Relationships

The neuropeptide oxytocin (OT) has emerged as a potent modulator of diverse aspects of interpersonal relationships. OT appears to work in close interaction with several other neurotransmitter networks, including the dopaminergic reward circuit, and to be dependent on sex-specific hormonal influences. In this chapter, we focus on four main domains of OT and interpersonal relationships, including (1) the protective effect of OT on an individual's ability to withstand stress (i.e., stress buffering), (2) the effect of OT on emotion recognition and empathy, (3) OT's ability to enhance social synchrony and cooperation among individuals, and (4) the effect of OT on an individual's perception of social touch. We then illustrate the connection between OT and loneliness while grieving the loss of a loved one. We finish by discussing the clinical potential of OT, focusing on its potential role as an adjunct to psychotherapy, its enhancement through sex-specific hormonal influences, and the difficulties that present themselves when considering OT as a therapy. Overall, we argue that OT continues to hold strong therapeutic promise, but that it is strongly dependent on internal and external influences, for instance the patient's personal past experiences and interaction with the therapist, in order to provide the best possible therapy.

Social Risk Screening for Pediatric Inpatients

This systematic review aims to identify existing social risk screening instruments applicable to hospitalized children (primary) and evaluate their content validity and methodological quality (secondary). Individual questions were abstracted and sorted by social risk theme. Content validity was evaluated by 13 hospital-based social workers. Methodological quality was assessed using the 108-item Consensus Based Standards for the Selection of Health Measurement Instruments (COSMIN) checklist. A total of 1070 citations were evaluated and 146 articles were reviewed, which identified 44 unique instruments. No instrument was applicable to social risk in hospitalized children. Sixty-one percent of instruments focused on a single social risk theme and only 18% of instruments covered more than 5 themes. The 2 instruments with the highest combination of social worker endorsement and COSMIN scores each addressed only 1 social risk theme relevant to hospitalized children. A broad, content valid and methodologically strong social risk screening instrument for hospitalized children was not identified.

The endocrinology of human caregiving and its intergenerational transmission

Variation in the quality of parental care has a tremendous impact on a child's social–emotional development. Research investigating the predictors of this variability in human caregiving behavior has mostly focused on learning mechanisms. Evidence is currently accumulating for the complementary underlying role of steroid hormones and neuropeptides. An overview is provided of the hormones and neuropeptides relevant for human caregiving behavior. Then the developmental factors are described that stimulate variability in sensitivity to these hormones and neuropeptides, which may result in variability in the behavioral repertoire of caregiving. The role of genetic variation in neuropeptide and steroid receptors, the role of testosterone and oxytocin during fetal development and parturition, and the impact of experienced caregiving in childhood on functioning of the neuroendocrine stress and oxytocin system are discussed. Besides providing a heuristic framework for further research on the ontogenetic development of human caregiving, a neuroendocrine model is also presented for the intergenerational transmission of caregiving practices. Insight into the underlying biological mechanisms that bring about maladaptive caregiving behavior, such as neglect and insensitive parenting, will hopefully result in more efficient approaches to reduce the high prevalence of such behavior and to minimize the impact on those affected.

Multilevel developmental approaches to understanding the effects of child maltreatment: Recent advances and future challenges

Recent research in the field of child maltreatment has begun to shed new light on the emergence of health problems in children by emphasizing the responsiveness of developmental processes to children's environmental and biological contexts. Here, I highlight recent trends in the field with an emphasis on the effects of early life stress across multiple levels of developmental domains.

Learning to trust: trust and attachment in early psychosis

BACKGROUND

Distrust and social dysfunction are characteristic in psychosis and may arise from attachment insecurity, which is elevated in the disorder. The relationship between trust and attachment in the early stages of psychosis is unknown, yet could help to understand interpersonal difficulties and disease progression. This study aimed to investigate whether trust is reduced in patients with early psychosis and whether this is accounted for by attachment avoidance and attachment anxiety.

METHOD

We used two trust games with a cooperative and unfair partner in a sample of 39 adolescents with early psychosis and 100 healthy controls.

RESULTS

Patients had higher levels of attachment anxiety, but the groups did not differ in attachment avoidance. Basic trust was lower in patients than controls, as indicated by lower initial investments. During cooperation patients increased their trust towards levels of controls, i.e. they were able to learn and to override initial suspiciousness. Patients decreased their trust less than controls during unfair interactions. Anxious attachment was associated with higher basic trust and higher trust during unfair interactions and predicted trust independent of group status. Discussion Patients showed decreased basic trust but were able to learn from the trustworthy behaviour of their counterpart. Worries about the acceptance by others and low self-esteem are associated with psychosis and attachment anxiety and may explain behaviour that is focused on conciliation, rather than self-protection.

Lower Oxytocin Plasma Levels in Borderline Patients with Unresolved Attachment Representations

Interpersonal problems and affective dysregulation are core characteristics of borderline personality disorder (BPD). BPD patients predominantly show unresolved attachment representations. The oxytocin (OT) system is associated with human social attachment and affiliative behavior, and OT dysregulation may be related to distinct attachment characteristics. Here, we investigated whether attachment representations are related to peripheral OT levels in BPD patients. Twenty-one female BPD patients and 20 age-, gender-, and education-matched healthy controls (HCs) were assessed with clinical scales and measures of interpersonal and attachment-related characteristics, including the Adult Attachment Projective Picture System (AAP). Plasma OT concentrations were measured prior to and during social exclusion in a virtual ball tossing game (Cyberball). The majority of BPD patients (63.2%) but no HCs showed unresolved (disorganized) attachment representations. In this subgroup of patients, baseline OT plasma levels were significantly lower than in BPD patients with organized attachment representations. This pilot study extends previous findings of altered OT regulation in BPD as a putative key mechanism underlying interpersonal dysregulation. Our results provide first evidence that altered OT plasma levels are related to disorganized attachment representations in BPD patients.

The Social Salience Hypothesis of Oxytocin

Oxytocin is a nonapeptide that also serves as a neuromodulator in the human central nervous system. Over the last decade, a sizeable body of literature has examined its effects on social behavior in humans. These studies show that oxytocin modulates various aspects of social behaviors such as empathy, trust, in-group preference, and memory of socially relevant cues. Several theoretical formulations have attempted to explain the effects of oxytocin. The prosocial account argues that oxytocin mainly enhances affiliative prosocial behaviors; the fear/stress theory suggests that oxytocin affects social performance by attenuating stress; and the in-/out-group approach proposes that oxytocin regulates cooperation and conflict among humans in the context of intergroup relations. Nonetheless, accumulating evidence reveals that the effects of oxytocin are dependent on a variety of contextual aspects and the individual's characteristics and can induce antisocial effects including aggression and envy. In an attempt to reconcile these accounts, we suggest a theoretical framework that focuses on the overarching role of oxytocin in regulating the salience of social cues through its interaction with the dopaminergic system. Crucially, the salience effect modulates attention orienting responses to external contextual social cues (e.g., competitive vs. cooperative environment) but is dependent on baseline individual differences such as gender, personality traits, and degree of psychopathology. This view could have important implications for the therapeutic applications of oxytocin in conditions characterized with aberrant social behavior.

Effects of the Social Environment and Stress on Glucocorticoid Receptor Gene Methylation: A Systematic Review

The early-life social environment can induce stable changes that influence neurodevelopment and mental health. Research focused on early-life adversity revealed that early-life experiences have a persistent impact on gene expression and behavior through epigenetic mechanisms. The hypothalamus-pituitary-adrenal axis is sensitive to changes in the early-life environment that associate with DNA methylation of a neuron-specific exon 17 promoter of the glucocorticoid receptor (GR) (Nr3c1). Since initial findings were published in 2004, numerous reports have investigated GR gene methylation in relationship to early-life experience, parental stress, and psychopathology. We conducted a systematic review of this growing literature, which identified 40 articles (13 animal and 27 human studies) published since 2004. The majority of these examined the GR exon variant 1F in humans or the GR17 in rats, and 89% of human studies and 70% of animal studies of early-life adversity reported increased methylation at this exon variant. All the studies investigating exon 1F/17 methylation in conditions of parental stress (one animal study and seven human studies) also reported increased methylation. Studies examining psychosocial stress and psychopathology had less consistent results, with 67% of animal studies reporting increased exon 17 methylation and 17% of human studies reporting increased exon 1F methylation. We found great consistency among studies investigating early-life adversity and the effect of parental stress, even if the precise phenotype and measures of social environment adversity varied among studies. These results are encouraging and warrant further investigation to better understand correlates and characteristics of these associations.

Developmental psychopathology: recent advances and future challenges

The integrative field of developmental psychopathology is having a huge impact on our understanding of human health and behavior. In this paper, I use the example of children's early stress exposure to illustrate how developmental psychopathologists now tend to deemphasize diagnostic categories and, instead, emphasize the social and biological contexts, events and circumstances that have created opportunities for maladaptive responses and health problems in youth. This example shows that developmental psychopathology is increasing understanding of how children develop the abilities that allow them to cope effectively with challenges and what leads to failures in development of these abilities. Integrating research about the neurobiology of learning may prove to be a powerful future direction to understand how the environment regulates behavior. Learning processes become increasingly intricate and fine-tuned as relevant neuroanatomical systems develop, and as the range, complexity and amount of environmental information increases for the developing child. A focus on these processes allows psychopathologists to formulate questions about which neural mechanisms children use to process information, how these mechanisms are themselves shaped by social context, why adverse social environments confer risk for children, and, perhaps, what sorts of neutrally informed interventions might remediate the deficits in self-regulation that underlie common psychopathologies.

MATERNAL DEPRESSION AND CHILD OXYTOCIN RESPONSE; MODERATION BY MATERNAL OXYTOCIN AND RELATIONAL BEHAVIOR

BACKGROUND

Maternal postpartum depression (PPD) carries long-term detrimental effects on children's well-being, yet the mechanisms of transmission remain unclear. One possible pathway of vulnerability involves the oxytocinergic (OT) system, which is transferred from mother to child via sensitive caregiving and is disrupted in PPD.

METHOD

A large birth cohort (N = 1983) of women were repeatedly assessed for depression from birth to 6 years. Utilizing an extreme case design, two matched cohorts were formed; mothers chronically depressed from birth to 6 years and nondepressed controls (N = 97, depressed = 41, nondepressed; N = 56). At 6 years, mothers and children underwent psychiatric diagnosis, urinary OT was assayed from mother and child before and after social contact, and mother-child interactions were coded.

RESULTS

Baseline OT and OT response of mother and child were interrelated and children of depressed mothers showed low baseline OT and attenuated OT response. Child OT response was negatively predicted by maternal depression, child Axis-I psychopathology, maternal expressed negative affect, and child social withdrawal. Interaction effect of maternal baseline OT and depression emerged. Slope analysis indicated that when maternal OT was medium or low, child OT response was negatively impacted by maternal depression. However, when maternal OT was high, child OT was unaffected, suggesting that maternal OT functionality buffers the effects of depression on the child.

CONCLUSION

Results suggest involvement of the OT system in the cross-generational transfer of vulnerability, as well as resilience, from depressed mothers to their children. Because the OT system is open to interventions that enhance maternal touch and contact, findings have important implications for targeted early dyadic inventions.

Early social deprivation and the social buffering of cortisol stress responses in late childhood: An experimental study

The goal of the present study was to investigate the role of early social deprivation in shaping the effectiveness of parent support to alleviate hypothalamic-pituitary-adrenal (HPA)-axis-stress responses of children (ages 8.9-11, M = 9.83 years, SD = .55). The sample was equally divided between children who had been adopted internationally from orphanage care by age 5 (n = 40) and an age- and gender-matched group of nonadopted (NA) children (n = 40). On average, internationally adopted children were invited to the laboratory 7.6 years postadoption (SD = 1.45). We experimentally manipulated the provision of parent support during the 5-min speech preparation period before a modified Trier Social Stress Test (TSST) and examined its effect on levels of salivary cortisol secreted in response to this laboratory stressor. All participants were randomly assigned to receive support from their parent or a stranger. Analyses revealed a significant interaction of support condition and group such that parent support significantly dampened the cortisol-stress response in NA children compared with support from a stranger, whereas the cortisol response curves of postinstitutionalized (PI) children did not differ between the parent- and stranger-support conditions. Cortisol reactivity for PI children in both conditions was lower than that of NA children in the stranger-support condition. Social deprivation during the first few years of life may shape neurobehavioral development in ways that reduce selective responses to caregivers versus strangers.

Context influences the interplay of endocrine axes across the day

The current investigation examined stressors upon the coupling of the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes. Emphasis is placed on the moderating role of context and time. One hundred and eighteen adolescent males and females provided up to 32 diurnal saliva samples across a visit to a research lab. This visit constituted a day-long stress through which the impact on HPA-HPG axis coupling could be assessed. We tested four models of HPA-HPG axis coupling across the lab day. Sex and stress hormones operated synchronously (β = .404, p < .001), and the coupling of sex and stress hormones was moderated by the stress of the lab day (β = .010, p = .05). This pattern of co-elevation did not appear to be moderated by the distal experience of early life adversity. Findings suggest that the notion of "stress" must disentangle proximal and distal challenges, each of which appears to impact neurobiological processes.

Association of oxytocin level and less severe forms of childhood maltreatment history among healthy Japanese adults involved with child care

Background: Oxytocin (OT) is known to play a role in stress regulation. The association between childhood maltreatment history and neuropeptide OT concentration is inconsistent due to the varying degrees of severity of childhood maltreatment, among other contributing factors. Less severe forms of childhood maltreatment history might enhance OT concentrations as a response to coping with social stress within the family. The purpose of this study is to investigate the association between less severe forms of childhood maltreatment history and OT concentrations among healthy adults.

Method: Eighty adults (49 women and 31 men) with 18- to 48-month-old children were recruited using a snowball sample in Tokyo, Japan. Urine samples were collected for OT measurement. Less severe (low and moderate) childhood maltreatment history, including physical abuse, physical neglect, emotional abuse, emotional neglect, and sexual abuse, was assessed using the self-report questionnaire, the Childhood Trauma Questionnaire.

Results: Less severe physical abuse was significantly associated with higher OT concentration after adjusting for age (p = 0.014). Also, less severe forms of physical abuse were independently significantly associated with higher OT concentration after controlling for other types of childhood maltreatment (p = 0.027). A positive dose-response association between the number of less severe childhood maltreatment types and OT concentration was observed (p = 0.031).

Conclusion: A history of less severe forms of childhood physical abuse was associated with higher OT concentration in healthy adults. Poly-victimization of several types of less severe childhood maltreatment was also associated with higher OT concentrations. Less severe forms of childhood maltreatment might enhance OT concentrations in order to cope with social stress.

Similar effects of intranasal oxytocin administration and acute alcohol consumption on socio-cognitions, emotions and behaviour: Implications for the mechanisms of action

Oxytocin (OT) plays a critical role in the formation of long lasting social attachments across a range of mammalian species. Raising intracerebral OT levels by intranasal administration of the neuropeptide (inOT) can also have pronounced effects on human sociocognitive functioning. inOT has been associated with increasing altruism, generosity, empathy and trust while decreasing fear, anxiety and stress reactions via neural mechanisms which are yet to be fully elucidated. The observation of the prosocial effects of OT has led to speculation about the role the peptide might play in some psychiatric conditions and debate as to its potential therapeutic uses. Here we note the great similarity in the sociocognitive effects that can be induced by inOT and the effects of acute consumption of modest does of alcohol. We further reflect on how both compounds may act on limbic and prefrontal cortical structures to increase GABAergic transmission, thereby facilitating the release of prepotent responses, that is, more automatic responses which are associated with earlier developmental stages.

The influence of early life sexual abuse on oxytocin concentrations and premenstrual symptomatology in women with a menstrually related mood disorder

Oxytocin (OT), associated with affiliation and social bonding, social salience, and stress/pain regulation, may play a role in the pathophysiology of stress-related disorders, including menstrually-related mood disorders (MRMD's). Adverse impacts of early life sexual abuse (ESA) on adult attachment, affective regulation, and pain sensitivity suggest ESA-related OT dysregulation in MRMD pathophysiology. We investigated the influence of ESA on plasma OT, and the relationship of OT to the clinical phenomenology of MRMD's. Compared to MRMD women without ESA (n=40), those with ESA (n=20) displayed significantly greater OT [5.39pg/mL (SD, 2.4) vs. 4.36pg/mL (SD, 1.1); t (58)=-2.26, p=0.03]. In women with ESA, OT was significantly, inversely correlated with premenstrual psychological and somatic symptoms (r's=-0.45 to -0.64, p's<0.05). The relationship between OT and premenstrual symptomatology was uniformly low and non-significant in women without ESA. In women with ESA, OT may positively modulate MRMD symptomatology.

Oxytocin, testosterone, and human social cognition

I describe an integrative social-evolutionary model for the adaptive significance of the human oxytocinergic system. The model is based on a role for this hormone in the generation and maintenance of social familiarity and affiliation across five homologous, functionally similar, and sequentially co-opted contexts: mothers with offspring, female and male mates, kin groups, individuals with reciprocity partners, and individuals within cooperating and competing social groups defined by culture. In each situation, oxytocin motivates, mediates and rewards the cognitive and behavioural processes that underlie the formation and dynamics of a more or less stable social group, and promotes a relationship between two or more individuals. Such relationships may be positive (eliciting neurological reward, reducing anxiety and thus indicating fitness-enhancing effects), or negative (increasing anxiety and distress, and thus motivating attempts to alleviate a problematic, fitness-reducing social situation). I also present evidence that testosterone exhibits opposite effects from oxytocin on diverse aspects of cognition and behaviour, most generally by favouring self-oriented, asocial and antisocial behaviours. I apply this model for effects of oxytocin and testosterone to understanding human psychological disorders centrally involving social behaviour. Reduced oxytocin and higher testosterone levels have been associated with under-developed social cognition, especially in autism. By contrast, some combination of oxytocin increased above normal levels, and lower testosterone, has been reported in a notable number of studies of schizophrenia, bipolar disorder and depression, and, in some cases, higher oxytocin involves maladaptively 'hyper-developed' social cognition in these conditions. This pattern of findings suggests that human social cognition and behaviour are structured, in part, by joint and opposing effects of oxytocin and testosterone, and that extremes of such joint effects partially mediate risks and phenotypes of autism and psychotic-affective conditions. These considerations have direct implications for the development of therapies for alleviating disorders of social cognition, and for understanding how such disorders are associated with the evolution of human cognitive-affective architecture.

Effect of the Nature of Subsequent Environment on Oxytocin and Cortisol Secretion in Maltreated Children

Childhood maltreatment (CM), including abuse and neglect, is a crucial factor that distorts child development. CM is associated with alterations in numerous brain regions, and may be associated with hormonal dysregulation. This study aimed to investigate differences in secretion patterns of cortisol (CT) and oxytocin (OT) among children who experienced CM, children living in residential care facilities and in unstable environments. Among 38 maltreated children, 23 (mean age = 12.2 years, SD = 3.0) were categorized as "Settled" and 15 (mean age = 13.1 years, SD = 2.2) as "Unsettled." Twenty-six age- and gender-matched (mean age = 12.6 years, SD = 2.1), typically developing (TD) children were also included. Clinical and psychological assessments, including IQ and trauma evaluations, were conducted for all participants. Age, gender, and full-scale IQ were used as covariates in hormone analysis. Two saliva samples were collected, one on awakening and the other at bedtime. There were significant differences in the awakening CT levels of the "Unsettled" group, and in bedtime OT levels in the "Settled" group as compared with TD children, and between CM groups. Furthermore, there was a significant difference in trauma-symptomatic depression scores between the "Settled" and "Unsettled" CM group. These results suggest that CT diurnal secretions tend to be reactive to current stress rather than previous experience. OT diurnal secretions are presumably hyper-regulated for coping with the environment to survive and thrive. By measuring salivary CT/OT diurnal patterns, hormonal dysregulation of CM children living in "Settled" environments and "Unsettled" environments was indicated.

Neurobiology of Maternal Stress: Role of Social Rank and Central Oxytocin in Hypothalamic-Pituitary Adrenal Axis Modulation

BACKGROUND

Chronic stress may conceivably require plasticity of maternal physiology and behavior to cope with the conflicting primary demands of infant rearing and foraging for food. In addition, social rank may play a pivotal role in mandating divergent homeostatic adaptations in cohesive social groups. We examined cerebrospinal fluid (CSF) oxytocin (OT) levels and hypothalamic-pituitary adrenal (HPA) axis regulation in the context of maternal social stress and assessed the contribution of social rank to dyadic distance as reflective of distraction from normative maternal-infant interaction.

METHODS

Twelve socially housed mother-infant bonnet macaque dyads were studied after variable foraging demand (VFD) exposure compared to 11 unstressed dyads. Dyadic distance was determined by behavioral observation. Social ranking was performed blindly by two observers. Post-VFD maternal plasma cortisol and CSF OT were compared to corresponding measures in non-VFD-exposed mothers.

RESULTS

High-social rank was associated with increased dyadic distance only in VFD-exposed dyads and not in control dyads. In mothers unexposed to VFD, social rank was not related to maternal cortisol levels, whereas VFD-exposed dominant versus subordinate mothers exhibited increased plasma cortisol. Maternal CSF OT directly predicted maternal cortisol only in VFD-exposed mothers. CSF OT was higher in dominant versus subordinate mothers. VFD-exposed mothers with "high" cortisol specifically exhibited CSF OT elevations in comparison to control groups.

CONCLUSION

Pairing of maternal social rank to dyadic distance in VFD presumably reduces maternal contingent responsivity, with ensuing long-term sequelae. VFD-exposure dichotomizes maternal HPA-axis response as a function of social rank with relatively reduced cortisol in subordinates. OT may serve as a homeostatic buffer during maternal stress exposure.

Cortisol responses to a group public speaking task for adolescents: variations by age, gender, and race

Laboratory social stress tests involving public speaking challenges are widely used for eliciting an acute stress response in older children, adolescents, and adults. Recently, a group protocol for a social stress test (the Trier Social Stress Test for Groups, TSST-G) was shown to be effective in adults and is dramatically less time-consuming and resource-intensive compared to the single-subject version of the task. The present study sought to test the feasibility and effectiveness of an adapted group public speaking task conducted with a racially diverse, urban sample of U.S. adolescents (N=191; 52.4% female) between the ages of 11 and 18 (M=14.4 years, SD=1.93). Analyses revealed that this Group Public Speaking Task for Adolescents (GPST-A) provoked a significant increase in cortisol production (on average, approximately 60% above baseline) and in self-reported negative affect, while at the same time avoiding excessive stress responses that would raise ethical concerns or provoke substantial participant attrition. Approximately 63.4% of participants exhibited an increase in cortisol levels in response to the task, with 59.2% of the total sample showing a 10% or greater increase from baseline. Results also suggested that groups of five adolescents might be ideal for achieving more uniform cortisol responses across various serial positions for speech delivery. Basal cortisol levels increased with age and participants belonging to U.S. national minorities tended to have either lower basal cortisol or diminished cortisol reactivity compared to non-Hispanic Whites. This protocol facilitates the recruitment of larger sample sizes compared to prior research and may show great utility in answering new questions about adolescent stress reactivity and development.

Oxytocin facilitates the sensation of social stress

Essentially all social species experience social stress which can be a catalyst for detriments in mental and physical health. The neuropeptide oxytocin (OXT) has been shown to produce anxiolytic and antistress effects, thereby qualifying the OXT system as a promising drug target in the treatment of stress-related disorders. However, recently it has been shown that OXT can have anxiogenic effects as well. In the present study, we used functional magnetic resonance imaging to scan the brains of 60 healthy men while they were exposed to social stress after they received either intranasal OXT (24 IU) or placebo treatment. Although OXT administration did not alter salivary cortisol levels as a surrogate marker of stress axis activity, our participants initially reported an increment in perceived social stress. This behavioral effect was paralleled on the neural level by increased activity in the precuneus and cingulate cortex. Taken together, our results support the hypothesis that OXT can induce a self-referential processing bias which facilitates the sensation of social stress in the absence of altered endocrine responses.

Psychosocial stress moderates the relationships between oxytocin, perinatal depression, and maternal behavior

The hormone oxytocin (OT) is of particular interest in the study of childbearing women, as it has a role in the onset and course of labor and breastfeeding. Recent research has linked OT to maternal caregiving behavior towards her infant, and to postpartum depressive symptomatology. There is also evidence that psychosocial adversity affects the oxytocin system. The present study investigated the relationship of endogenous OT in women during pregnancy and at 8weeks postpartum to psychosocial stress, maternal symptoms of depression, and maternal sensitive behavior. It was hypothesized that OT would mediate the effects of maternal depressive symptoms on maternal interactive behavior. We also tested the hypothesis that psychosocial stress would moderate the relationship between OT and maternal depressive symptoms and sensitive behavior. A community sample of 287 women was assessed at 12-14weeks of gestation, 32-34weeks of gestation, and 7-9weeks postpartum. We measured plasma OT, maternal symptoms of depression and psychosocial stress. At the postpartum home visit, maternal behavior in interaction with the infant was videotaped, and then coded to assess sensitivity. In the sample as a whole, OT was not related to maternal depressive symptoms or to sensitive maternal behavior. However, among women who reported high levels of psychosocial stress, higher levels of plasma OT were associated with fewer depressive symptoms and more sensitive maternal behavior. These results suggest that endogenous OT may act as a buffer against the deleterious effects of stress, thereby protecting high risk women from developing depressive symptoms and promoting more sensitive maternal interactive behavior.

The biological effects of childhood trauma

Trauma in childhood is a psychosocial, medical, and public policy problem with serious consequences for its victims and for society. Chronic interpersonal violence in children is common worldwide. Developmental traumatology, the systemic investigation of the psychiatric and psychobiological effects of chronic overwhelming stress on the developing child, provides a framework and principles when empirically examining the neurobiological effects of pediatric trauma. This article focuses on peer-reviewed literature on the neurobiological sequelae of childhood trauma in children and in adults with histories of childhood trauma.

Maltreated youth display a blunted blood pressure response to an acute interpersonal stressor

Although there is much evidence of hypothalamic-pituitary-adrenal axis dysfunction among individuals who have experienced child maltreatment, dysregulation of the autonomic nervous system (ANS) has received less attention. Understanding the role of the ANS in maltreated children may help clarify how these children respond to subsequent life stress. We explored ANS reactivity among 111 youth (ages 9-14), 34 of whom had experienced verified child maltreatment. ANS activity was assessed via blood pressure-a convenient, noninvasive physiological index-while youth underwent a social stress task. Blood pressure and subjective mood ratings were obtained prior to and following the task. Nonmaltreated youth experienced an increase in systolic blood pressure following the stressor, whereas maltreated youth did not. Self-reported subjective mood worsened for both groups. The current data suggest that children who experienced early stress exposure demonstrate blunted ANS reactivity. Results are discussed in terms of children's healthy adaptations to transient social stressors. In addition, we discuss the cost-effectiveness and benefits of physiological measures such as blood pressure for understanding risk for psychopathology.