Early experience in humans is associated with changes in neuropeptides critical for regulating social behavior

Dissociative Amnesia: Remembrances Under Cover

The existence or questionability of "repressed memories" can be discussed as being a matter of definition. It seems, however, far-fetched to consider all "lost" memories as caused by encoding problems, brain damage, forgetfulness, failure to disclose events, and so on. We argue that dissociative amnesia (DA) (or "psychogenic amnesia," or "functional amnesia," or, as we favor to call it, "mnestic block syndrome") is caused by psychic alterations, but ultimately they can be traced to changes in the physiology of the brain, as we are of the opinion that all memory processes-positive or negative-alter brain functions, sometimes more permanently, sometimes transiently. We have proven this idea using functional imaging techniques, in particular fluoro-deoxy-d-glucose positron emission tomography. Having investigated dozens of patients with severe and long-lasting DA conditions, we believe it to be disrespectful to many (but not to all) of the affected patients to question their disease condition, which can be proven to be not caused by feigning, malingering, or direct brain damage.

Longitudinal Assessment of Hair Cortisol as a Predictor of Psychological Symptoms During COVID-19

BACKGROUND

There is a lack of evidence regarding enduring psychoneuroendocrine changes following an initial traumatic event, particular in the presence of an ongoing stressor. The coronavirus pandemic presents an opportunity to explore this matter. Consequently, the purpose of the present study was to investigate the impact of the ongoing pandemic (2021) on individuals, who experienced a first-time motor vehicle crash (MVC) at least 6 years earlier. To this end, we hypothesized that hair cortisol concentrations (HCC) following a first-time traumatic event positively predict symptoms of depression.

METHOD

We investigated N = 69 individuals (18 - 65 yrs.), who were victims of a MVC during 2010 - 2014. Hair strands were collected 10 days (t1) and 3 months after the MVC (t2), as well during the pandemic in 2021 (t3). To assess symptoms of depression, the participants filled out the Beck Depression Inventory at t1 - t3 and were additionally interviewed (Structured Clinical Interview for DSM-IV Axis I) at t1 and t2. Exclusion criteria conveyed a lifetime or acute mental disorder (incl. past trauma exposure).

RESULTS

Elevated pre-pandemic HCC following adversity (i.e., MVC) significantly predicted symptoms of depression in adults during the coronavirus pandemic (BDI: ß =.44, p =.010, R2 =.20), even after controlling for confounders. HCC significantly decreased over time, while in average psychological symptoms remained consistent.

CONCLUSION

Cortisol dysregulation in the past presents an enduring vulnerability to ongoing stress. In this regard, vulnerable groups may benefit from preventive measures. This finding validates the predictive power of HCC and extended past evidence in this regard, at the same time reinforcing the concept of the diathesis-stress model.

The neurobiological effects of childhood maltreatment on brain structure, function, and attachment

Childhood maltreatment is a risk factor for psychopathologies, and influences brain development at specific periods, particularly during early childhood and adolescence. This narrative review addresses phenotypic alterations in sensory systems associated with specific types of childhood maltreatment exposure, periods of vulnerability to the neurobiological effects of maltreatment, and the relationships between childhood maltreatment and brain structure, function, connectivity, and network architecture; psychopathology; and resilience. It also addresses neurobiological alterations associated with maternal communication and attachment disturbances, and uses laboratory-based measures during infancy and case-control studies to elucidate neurobiological alterations in reactive attachment disorders in children with maltreatment histories. Moreover, we review studies on the acute effects of oxytocin on reactive attachment disorder and maltreatment and methylation of oxytocin regulatory genes. Epigenetic changes may play a critical role in initiating or producing the atypical structural and functional brain alterations associated with childhood maltreatment. However, these changes could be reversed through psychological and pharmacological interventions, and by anticipating or preventing the emergence of brain alterations and subsequent psychopathological risks.

Investigating postsynaptic effects of a Drosophila neuropeptide on muscle contraction

The Drosophila neuropeptide, DPKQDFMRFamide, was previously shown to enhance excitatory junctional potentials (EJPs) and muscle contraction by both presynaptic and postsynaptic actions. Since the peptide acts on both sides of the synaptic cleft, it has been difficult to examine postsynaptic modulatory mechanisms, particularly when contractions are elicited by nerve stimulation. Here, postsynaptic actions are examined in 3rd instar larvae by applying peptide and the excitatory neurotransmitter, l-glutamate, in the bathing solution to elicit contractions after silencing motor output by removing the central nervous system (CNS). DPKQDFMRFamide enhanced glutamate-evoked contractions at low concentrations (EC50 1.3 nM), consistent with its role as a neurohormone, and the combined effect of both substances was supra-additive. Glutamate-evoked contractions were also enhanced when transmitter release was blocked in temperature-sensitive (Shibire) mutants, confirming the peptide's postsynaptic action. The peptide increased membrane depolarization in muscle when co-applied with glutamate, and its effects were blocked by nifedipine, an L-type channel blocker, indicating effects at the plasma membrane involving calcium influx. DPKQDFMRFamide also enhanced contractions induced by caffeine in the absence of extracellular calcium, suggesting increased calcium release from the sarcoplasmic reticulum (SR) or effects downstream of calcium release from the SR. The peptide's effects do not appear to involve calcium/calmodulin-dependent protein kinase II (CaMKII), previously shown to mediate presynaptic effects. The approach used here might be useful for examining postsynaptic effects of neurohormones and cotransmitters in other systems.NEW & NOTEWORTHY Distinguishing presynaptic and postsynaptic effects of neurohormones is a long-standing challenge in many model organisms. Here, postsynaptic actions of DPKQDFMRFamide are demonstrated by assessing its ability to potentiate contractions elicited by direct application of the neurotransmitter, glutamate, when axons are silent and when transmitter release is blocked. The peptide acts at multiple sites to increase contraction, increasing glutamate-induced depolarization at the cell membrane, acting on L-type channels, and acting downstream of calcium release from the sarcoplasmic reticulum.

Endogenous oxytocin and human social interactions: A systematic review and meta-analysis

While there has been an increase in studies investigating the relationship between endogenous oxytocin (OXT) concentrations and human social interactions over the past decades, these studies still seem far from converging, both in methodological terms and in terms of their results. This systematic review and meta-analysis were aimed at a comprehensive evaluation and synthesis of empirical evidence on the relationship between endogenous OXT concentrations and human social interactions by reviewing studies published between 1970 and July 2020 and addressing various related methodological and analytical limitations. Sixty-three studies were included in the qualitative synthesis, and results from 51 studies were pooled in a meta-analysis (n = 3,741 participants). The results indicated that social interaction did not lead to an expected hormonal response in causal designs, either in a pre-post design (g = 0.079) or when comparing experimental conditions with and without social interaction (g = 0.256). However, in correlational designs, the overall mean effect size (ES) of the correlations between indicators of social interaction and OXT concentrations was significantly different from zero (z = 0.137). In both designs, subgroup analyses revealed that studies involving either parent-child interactions, or the utilization of the enzyme-linked immunosorbent assay method for OXT analysis, or unrestricted eating, drinking, or exercise before biofluid collection showed significantly higher than zero mean ESs. This review exposes the observed inconsistencies and suggests that standardized, replicable, and reliable approaches to assessing social interaction and measuring OXT concentrations need to be developed to study neurochemical mechanisms of sociality in humans. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Environmental modifications to rehabilitate social behavior deficits after acquired brain injury: What is the evidence?

Social behavior deficits are a common, debilitating consequence of traumatic brain injury and stroke, particularly when sustained during childhood. Numerous factors influence the manifestation of social problems after acquired brain injuries, raising the question of whether environmental manipulations can minimize or prevent such deficits. Here, we examine both clinical and preclinical evidence addressing this question, with a particular focus on environmental enrichment paradigms and differing housing conditions. We aimed to understand whether environmental manipulations can ameliorate injury-induced social behavior deficits. In summary, promising data from experimental models supports a beneficial role of environmental enrichment on social behavior. However, limited studies have considered social outcomes in the chronic setting, and few studies have addressed the social context specifically as an important component of the post-injury environment. Clinically, limited high-caliber evidence supports the use of specific interventions for social deficits after acquired brain injuries. An improved understanding of how the post-injury environment interacts with the injured brain, particularly during development, is needed to validate the implementation of rehabilitative interventions that involve manipulating an individuals' environment.

Neuroendocrine mechanisms contributing to the coevolution of sociality and communication

Communication is inherently social, so signaling systems should evolve with social systems. The 'social complexity hypothesis' posits that social complexity necessitates communicative complexity and is generally supported in vocalizing mammals. This hypothesis, however, has seldom been tested outside the acoustic modality, and comparisons across studies are confounded by varying definitions of complexity. Moreover, proximate mechanisms underlying coevolution of sociality and communication remain largely unexamined. In this review, we argue that to uncover how sociality and communication coevolve, we need to examine variation in the neuroendocrine mechanisms that coregulate social behavior and signal production and perception. Specifically, we focus on steroid hormones, monoamines, and nonapeptides, which modulate both social behavior and sensorimotor circuits and are likely targets of selection during social evolution. Lastly, we highlight weakly electric fishes as an ideal system in which to comparatively address the proximate mechanisms underlying relationships between social and signal diversity in a novel modality.

The evolved nest, oxytocin functioning, and prosocial development

Prosociality, orientation to attuned, empathic relationships, is built from the ground up, through supportive care in early life that fosters healthy neurobiological structures that shape behavior. Numerous social and environmental factors within early life have been identified as critical variables influencing child physiological and psychological outcomes indicating a growing need to synthesize which factors are the most influential. To address this gap, we examined the influence of early life experiences according to the evolved developmental niche or evolved nest and its influence on child neurobiological and sociomoral outcomes, specifically, the oxytocinergic system and prosociality, respectively. To-date, this is the first review to utilize the evolved nest framework as an investigatory lens to probe connections between early life experience and child neurobiological and sociomoral outcomes. The evolved nest is comprised of characteristics over 30 million years old and is organized to meet a child's basic needs as they mature. Converging evidence indicates that humanity's evolved nest meets the needs of a rapidly developing brain, optimizing normal development. The evolved nest for young children includes soothing perinatal experiences, breastfeeding, positive touch, responsive care, multiple allomothers, self-directed play, social embeddedness, and nature immersion. We examined what is known about the effects of each evolved nest component on oxytocinergic functioning, a critical neurobiological building block for pro-sociomorality. We also examined the effects of the evolved nest on prosociality generally. We reviewed empirical studies from human and animal research, meta-analyses and theoretical articles. The review suggests that evolved nest components influence oxytocinergic functioning in parents and children and help form the foundations for prosociality. Future research and policy should consider the importance of the first years of life in programming the neuroendocrine system that undergirds wellbeing and prosociality. Complex, interaction effects among evolved nest components as well as among physiological and sociomoral processes need to be studied. The most sensible framework for examining what builds and enhances prosociality may be the millions-year-old evolved nest.

Oxytocin as a Biomarker of Differential Effects to SPACE vs. CBT Treatment of Child Anxiety Disorders

OBJECTIVE

Two lines of research, on outcome moderators and on novel treatment targets, seek to improve the overall efficacy of child anxiety treatment, with mixed results. We propose that an integration of both lines of research can lead to improved treatment efficacy. In a first proof of concept of this approach, we studied whether the interaction between baseline levels and targeted changes in peripheral oxytocin (OT) can predict differential responses to two childhood anxiety treatments.

METHOD

A total of 124 mother-child dyads participated in the study. Children's salivary OT levels were measured at baseline and again, immediately after an experimental dyadic interaction in the lab. Dyads were subsequently randomized to receive one of two treatments, differing in their targets: SPACE (Supportive Parenting for Anxious Childhood Emotions) and CBT (cognitive-behavioral therapy). Treatment outcomes were assessed using the Childhood Anxiety Related Emotional Disorders scale, reported by both mother and child.

RESULTS

The findings suggest that in SPACE, where the mother is the main agent of change, higher baseline levels of child OT, coupled with increases in OT following a positive mother-child interaction, predicted greater treatment efficacy. By contrast, in CBT, where the child is the main agent of change, higher baseline levels of child OT, coupled with a decrease in OT following the interaction, predicted greater treatment efficacy.

CONCLUSIONS

The findings highlight the importance of the integration between moderators and targets of treatments for progress toward improving treatment efficacy through precision medicine.

Maternal distress, DNA methylation, and fetal programing of stress physiology in Brazilian mother-infant pairs

Maternal prenatal psychosocial stress is associated with adverse hypothalamic-pituitary-adrenal axis (HPAA) function among infants. Although the biological mechanisms influencing this process remain unknown, altered DNA methylation is considered to be one potential mechanism. We investigated associations between maternal prenatal psychological distress, infant salivary DNA methylation, and stress physiology at 12 months. Mother's distress was measured via depression and anxiety in early and late pregnancy in a cohort of 80 pregnant adolescents. Maternal hair cortisol was collected during pregnancy. Saliva samples were collected from infants at 12 months to quantify DNA methylation of three stress-related genes (FKBP5, NR3C1, OXTR) (n = 62) and diurnal cortisol (n = 29). Multivariable linear regression was used to test for associations between prenatal psychological distress, and infant DNA methylation and cortisol. Hair cortisol concentrations in late pregnancy were negatively associated with two sites of FKBP5 (site 1: B = -22.33, p = .003; site 2: B = -15.60, p = .012). Infants of mothers with elevated anxiety symptoms in late pregnancy had lower levels of OXTR2 CpG2 methylation (B = -2.17, p = .03) and higher evening salivary cortisol (B = 0.41, p = .03). Furthermore, OXTR2 methylation was inversely associated with evening cortisol (B = -0.14, p-value ≤ .001). Our results are, to our knowledge, the first evidence that the methylation of the oxytocin receptor may contribute to the regulation of HPAA during infancy.

Preliminary data on oxytocin modulation of neural reactivity in women to emotional stimuli of children depending on childhood emotional neglect

Sensitivity for rewarding cues and distress signals from children is fundamental to human caregiving and modulated by the neuropeptide oxytocin. In a functional magnetic resonance imaging study, we investigated whether oxytocin regulates neural responses to reward or distress cues form children. In a placebo-controlled, within-subject design, we measured neural responses to positive, negative, and neutral cues from children in 22 healthy female subjects who received oxytocin (24 IU) versus placebo. Further, based on current literature, we hypothesized that oxytocin effects are modulated by experiences of childhood trauma. The task elicited valence-specific effects-positive images activated the ventromedial prefrontal cortex, left anterior cingulate cortex, and right putamen, and images of children in distress activated the bilateral amygdala, hippocampus, and right medial superior frontal cortex. The effects of oxytocin depended on subjective reports of childhood emotional neglect. Self-reported neglect interacted with oxytocin administration in the amygdala, hippocampus, and prefrontal areas. In individuals with higher scores of emotional neglect, oxytocin increased neural reactivity of limbic structures to positive and neutral images. Our findings need replication in larger samples and can therefore be considered preliminary but are in line with the recent literature on the modulating effect of childhood adversity on the sensitivity to oxytocin administration.

Family-based care buffers the stress sensitizing effect of early deprivation on executive functioning difficulties in adolescence

We examined whether family care following early-life deprivation buffered the association between stressful life events (SLEs) and executive functioning (EF) in adolescence. In early childhood, 136 institutionally reared children were randomly assigned to foster care or care-as-usual; 72 never-institutionalized children served as a comparison group. At age 16 years, adolescents (n = 143; 54% female; 67.1% Romanian) self-reported recent SLEs, completed a battery of memory and EF tasks, and completed a go/nogo task in which mediofrontal theta power (MFTP) was measured using electroencephalogram. More independent SLEs predicted lower EF and more dependent SLEs predicted lower MFTP, but only among adolescents with prolonged early deprivation. Findings provide preliminary evidence that family care following early deprivation may facilitate resilience against stress during adolescence on EF.

Review of the Current Knowledge of Reactive Attachment Disorder

Reactive attachment disorder (RAD), classified under Trauma and Stressor Related Disorders in the DSM-5 manual, is a childhood psychiatric illness due to familial or social neglect or due to maltreatment. It is characterized by an inhibited and withdrawn social and emotional behavior toward an adult caregiver, typically before the age of 5. Neurobiological changes in patients with RAD have been shown to be substantially significant with features such as loss of grey matter volume and neurotransmitter deficiencies that not only impact the ability to form healthy attachments but also increase the risk of comorbidities such as depression and anxiety. Different theories, including the current mediation hypothesis and learning theory of attachment, showed childhood maltreatment from caregivers and desensitization toward deficiencies in social development in children from special education teachers to be key components in the development of RAD. Patients with RAD had an increased risk of developing psychiatric comorbidities, including learning disabilities and mood disorders. Institutionalized care and childhood maltreatment have a significant impact on the development of RAD. RAD is an underdiagnosed and underreported condition with significant repercussions that can severely impact the development of a child. By being able to raise awareness and promote further research into refining the diagnostic methodology, treatment protocols, and long-term follow-up, children afflicted with this condition may be able to develop better socio-emotional bonds and reduce the incidence of comorbidities such as depression and attention deficit hyperactivity disorder.

Infant Stimulation Induced a Rapid Increase in Maternal Salivary Oxytocin

Oxytocin (OT) is a neuropeptide involved in human social behaviors and reproduction. Non-invasive OT levels in saliva have recently roused interest as it does not require a specialized medical setting. Here, we observed one woman’s basal serum and saliva OT from pregnancy to 1 year postpartum to track OT concentration changes over this period. We examined the changes in salivary OT levels over time in response to maternal physiological and behavioral responses. The fluctuation of saliva OT levels is well correlated with serum OT during pregnancy and breastfeeding. However, while salivary OT increased rapidly during direct interaction (social interaction tests) with the infant and/or when the mother was watching her own infant’s video (video tests), no increase was observed in serum. We used social interaction and video tests on a group of mothers (nine mothers for social interaction and six for the video test) to clarify these single-subject results. In both tests, the mothers had increased OT in their saliva but not serum. Our study may suggest that salivary samples reflect not only the physical but also the emotional state and that saliva samples may be useful for monitoring women’s OT levels during pre- and postpartum periods. Further studies with larger sample numbers are necessary to confirm the rapid changes in salivary OT levels in response to maternal physiological and behavioral responses.

Peripheral oxytocin concentrations in psychiatric disorders - A systematic review and methanalysis: Further evidence

Increased interest in understanding how changes in the oxytocinergic system are associated with the etiology and progression of psychiatric disorders has currently boosted the publication of studies. We present a systematic literature review followed by meta-analyses assessing whether peripheral oxytocin (OXT) levels among psychiatric patients differ from healthy controls, considering the moderating role of methodological aspects and samples' characteristics. The following electronic databases were searched: PubMed, Web of Science, PsycINFO, SciELO, LILACS, and Scopus. Fifty-five papers were included in the analysis, and nine independent meta-analyses were performed according to the different diagnoses. Lower OXT concentrations were found in groups of specific disorders (i.e., schizophrenia, restricting and binge-eating/purging subtypes of anorexia nervosa, and borderline personality disorder) with medium to large effect sizes. Great heterogeneity was found among the studies, so that caution is needed to interpret the results. High OXT levels with an effect size of the same magnitude were found for bipolar disorder - type I and obsessive disorder. In contrast, no differences were found for bulimia, autism spectrum, depression, or social anxiety. No meta-analyses were performed for body dysmorphic disorder, post-traumatic stress disorder, or trichotillomania because only one study was identified for each of these disorders. Altered endogenous OXT concentrations are found in several disorders addressed and must be analyzed according to each disorder's specificities.

On the Interplay Between the Medicine of Hildegard of Bingen and Modern Medicine: The Role of Estrogen Receptor as an Example of Biodynamic Interface for Studying the Chronic Disease's Complexity

Introduction

Hildegard of Bingen (1098-1179) interpreted the origins of chronic disease highlighting and anticipating, although only in a limited fashion, the importance that complex interactions among numerous genetic, internal milieu and external environmental factors have in determining the disease phenotype. Today, we recognize those factors, capable of mediating the transmission of messages between human body and environment and vice versa, as biodynamic interfaces.

Aim

We analyzed, in the light of modern scientific evidence, Hildegard of Bingen's medical approach and her original humoral theory in order to identify possible insights included in her medicine that could be referred to in the context of modern evidence-based medicine. In particular, the abbess's humoral theory suggests the identification of biodynamic interfaces with sex hormones and their receptors.

Findings

We found that the Hildegardian holistic vision of the organism-environment relationship can actually represent a visionary approach to modern endocrinology and that sex hormones, in particular estrogens, could represent an example of a biodynamic interface. Estrogen receptors are found in regions of the brain involved in emotional and cognitive regulation, controlling the molecular mechanism of brain function. Estrogen receptors are involved in the regulation of the hypothalamic-pituitary-adrenal axis and in the epigenetic regulation of responses to physiological, social, and hormonal stimuli. Furthermore, estrogen affects gene methylation on its own and related receptor promoters in discrete regions of the developing brain. This scenario was strikingly perceived by the abbess in the XIIth century, and depicted as a complex interplay among different humors and flegmata that she recognized to be sex specific and environmentally regulated.

Viewpoint

Considering the function played by hormones, analyzed through the last scientific evidence, and scientific literature on biodynamic interfaces, we could suggest Hildegardian insights and theories as the first attempt to describe the modern holistic, sex-based medicine.

Conclusion

Hildegard anticipated a concept of pathogenesis that sees a central role for endocrinology in sex-specific disease. Furthermore, estrogens and estrogen receptors could represent a good example of molecular interfaces capable of modulating the interaction between the organism internal milieu and the environmental factors.

Utility of Downstream Biomarkers to Assess and Optimize Intranasal Delivery of Oxytocin

Oxytocin (OT), a mammalian neurohormone associated with social cognition and behavior, can be administered in its synthetic form intranasally (IN) and impact brain chemistry and behavior. IN-OT shows potential as a noninvasive intervention for disorders characterized by social challenges, e.g., autism spectrum disorder (ASD) and anorexia nervosa (AN). To evaluate IN-OT’s efficacy, we must quantify OT uptake, availability, and clearance; thus, we assessed OT levels in urine (uOT) before and after participants (26 ASD, 7 AN, and 7 healthy controls) received 40 IU IN-OT or placebo across two sessions using double-blind, placebo-controlled crossover designs. We also measured uOT and plasma (pOT) levels in a subset of participants to compare the two sampling methods. We found significantly higher uOT and pOT following intranasal delivery of active compound versus placebo, but analyses yielded larger effect sizes and more clearly differentiated pre–post-OT levels for uOT than pOT. Further, we applied a two-step cluster (TSC), blinded backward-chaining approach to determine whether active/placebo groups could be identified by uOT and pOT change alone; uOT levels may serve as an accessible and accurate systemic biomarker for OT dose–response. Future studies will explore whether uOT levels correlate directly with behavioral targets to improve dosing for therapeutic goals.

What is the expected human childhood? Insights from evolutionary anthropology

In psychological research, there are often assumptions about the conditions that children expect to encounter during their development. These assumptions shape prevailing ideas about the experiences that children are capable of adjusting to, and whether their responses are viewed as impairments or adaptations. Specifically, the expected childhood is often depicted as nurturing and safe, and characterized by high levels of caregiver investment. Here, we synthesize evidence from history, anthropology, and primatology to challenge this view. We integrate the findings of systematic reviews, meta-analyses, and cross-cultural investigations on three forms of threat (infanticide, violent conflict, and predation) and three forms of deprivation (social, cognitive, and nutritional) that children have faced throughout human evolution. Our results show that mean levels of threat and deprivation were higher than is typical in industrialized societies, and that our species has experienced much variation in the levels of these adversities across space and time. These conditions likely favored a high degree of phenotypic plasticity, or the ability to tailor development to different conditions. This body of evidence has implications for recognizing developmental adaptations to adversity, for cultural variation in responses to adverse experiences, and for definitions of adversity and deprivation as deviation from the expected human childhood.

Longitudinal Influences of DRD4 Polymorphism and Early Maternal Caregiving on Personality Development and Problem Behavior in Middle Childhood and Adolescence

Most studies examining gene-environment effects on self-regulation focus on outcomes early childhood or adulthood. However, only a few studies investigate longitudinal effects during middle childhood and adolescence and compare two domains of early caregiving. In a longitudinal follow-up with a sample of N = 87, we studied the effects of differences in the DRD4 tandem repeat polymorphisms and two domains of early maternal caregiving quality on children’s personality development using Block’s California Child Q-Set (CCQ) at age six and age 12 and on problem behavior at ages six and seven. Early maternal regulation quality predicted later ego-resiliency and aggressiveness. In addition, significant gene-environment interactions revealed that children with the 7+ DRD4 tandem repeat polymorphism and poor maternal regulation quality in infancy showed lower scores in ego-resiliency and higher scores in ego-undercontrol and CCQ aggressiveness. In contrast, children who had experienced effective maternal regulation in infancy showed a comparable level in personality traits and problem behavior as the DRD4 7- group independent of the levels of maternal regulatory behavior. Similarly, longitudinal caregiving × DRD4 interactions were found for behavior problems in middle childhood, especially for oppositional-aggression, inattentive-hyperactivity, and social competence. Early caregiving effects were only found for maternal regulation quality, but not for maternal responsiveness. Effective early maternal regulation in infancy can moderate the negative effect of DRD4 7+ on children’s self-regulation in middle childhood and adolescence. However, maternal responsiveness has no comparable effects. It seems relevant to consider several dimensions of early caregiving and to also measure the environment in more detail in gene-environment studies.

Time-frequency analysis methods and their application in developmental EEG data

EEG provides a rich measure of brain activity that can be characterized as neuronal oscillations. However, most developmental EEG work to date has focused on analyzing EEG data as Event-Related Potentials (ERPs) or power based on the Fourier transform. While these measures have been productive, they do not leverage all the information contained within the EEG signal. Namely, ERP analyses ignore non-phase-locked signals and Fourier-based power analyses ignore temporal information. Time-frequency analyses can better characterize the oscillations contained in the EEG data. By separating power and phase information across different frequencies, time-frequency measures provide a closer interpretation of the neurophysiological mechanisms, facilitate translation across neurophysiology disciplines, and capture processes not observed by ERP or Fourier-based analyses (e.g., connectivity). Despite their unique contributions, a literature review of this journal reveals that time-frequency analyses of EEG are yet to be embraced by the developmental cognitive neuroscience field. This manuscript presents a conceptual introduction to time-frequency analyses for developmental researchers. To facilitate the use of time-frequency analyses, we include a tutorial of accessible scripts, based on Cohen (2014), to calculate time-frequency power (signal strength), inter-trial phase synchrony (signal consistency), and two types of phase-based connectivity (inter-channel phase synchrony and weighted phase lag index).

Oxytocin receptor expression and epigenetic regulation in the anterior cingulate cortex of individuals with a history of severe childhood abuse

Childhood abuse significantly increases the lifetime risk of negative mental health outcomes. The oxytocinergic system, which plays a role in complex social and emotional behaviors, has been shown to be sensitive to early-life experiences. While previous studies have investigated the relationship between early-life adversity and oxytocin, they did so with peripheral samples. We, therefore, aimed to characterize the relationship between early-life adversity and oxytocin receptor (OXTR) expression in the brain, using post-mortem human samples, as well as a rodent model of naturally occurring variation in early-life environment. Focusing on the dorsal anterior cingulate cortex, we compared OXTR expression and epigenetic regulation between MDD suicides with (N = 26) and without history of childhood abuse (N = 24), as well as psychiatrically healthy controls (N = 23). We also compared Oxtr expression in the cingulate cortex of adult rats raised by dams displaying high (N = 13) and low levels (N = 12) of licking and grooming (LG) behavior. Overall, our results indicate that childhood abuse associates with an upregulation of OXTR expression, and that similarly, this relationship is also observed in the cingulate cortex of adult rats raised by low-LG dams. Additionally, we found an effect of rs53576 genotype on expression, showing that carriers of the A variant also show upregulated OXTR expression. The effects of early-life adversity and rs53576 genotype on OXTR expression are, however, not explained by differences in DNA methylation within and around the MT region of the OXTR gene.

Early Life Adversity and Males: Biology, Behavior, and Implications for Fathers' Parenting

Fathers have an important and unique influence on child development, but influences on fathers' parenting have been vastly understudied in the scientific literature. In particular, very little empirical research exists on the effects of early life adversity (ELA; e.g. childhood maltreatment, parental separation) on later parenting among fathers. In this review, we draw from both the human and non-human animal literature to examine the effects of ELA, specifically among males, in the following areas: 1) neurobiology and neurocognitive functioning, 2) hormones and hormone receptors, 3) gene-environment interactions and epigenetics, and 4) behavior and development. Based on these findings, we present a conceptual model to describe the biological and behavioral pathways through which exposure to ELA may influence parenting among males, with a goal of guiding future research and intervention development in this area. Empirical studies are needed to improve understanding of the relationship between ELA and father's parenting, inform the development of paternal and biparental interventions, and prevent intergenerational transmission of ELA.

An improved sample extraction method reveals that plasma receptor for advanced glycation end-products (RAGE) modulates circulating free oxytocin in mice

The receptor for advanced glycation end-products (RAGE) binds oxytocin (OT) and transports it from the blood to the brain. As RAGE's OT-binding capacity was lost in RAGE knockout (KO) mice, we predicted that circulating concentrations of unbound (free) OT should be elevated compared to wild-type (WT) mice. However, this hypothesis has not yet been investigated. Unfortunately, the evaluation of the dynamics of circulating free and bound plasma OT is unclear in immunoassays, in part because of interference from plasma proteins. A radioimmunoassay (RIA) is considered the gold standard method for overcoming this issue, but is more challenging to implement; thus, commercially available enzyme-linked immunosorbent assays (ELISAs) are more commonly used. Here, we developed a pre-treatment method to remove the interference-causing components from plasma before performing ELISA. The acetonitrile protein precipitation (PPT) approach was reliable, with fewer steps needed to measure free OT concentrations than by solid-phase extraction of plasma samples. PPT-extracted plasma samples yielded higher concentrations of OT in RAGE KO mice than in WT mice using ELISA. After peripheral OT injection, free OT plasma levels spiked immediately then rapidly declined in WT mice, but remained high in KO mice. These results suggest that plasma samples with PPT pre-treatment appear to be superior and that circulating soluble RAGE can most likely serve as a buffer for plasma OT, which indicates a novel physiological function of RAGE.

Social relationships and children’s perceptions of adversity

Having sensitive, contingent, and supportive social relationships has been linked to more positive outcomes after experiences of early childhood adversity. Traditionally, social relationships are construed as moderators that buffer children from the effects of exposure to adverse events. However, recent data support an alternative view: that supportive social relationships influence children’s later outcomes by shaping their perceptions of safety and stress, regardless of the particular events to which children are exposed. This perspective has implications for understanding vulnerability and resilience in children.

Maternal Bonding in Early Infancy Predicts Childrens' Social Competences in Preschool Age

Background: There are many studies on mother-child-bonding with little theoretical doubt that better bonding may have a positive effect on further social development. However, there is hardly any empirical evidence. In particular, there is a lack prospective longitudinal studies. Methods: As part of a longitudinal study, bonding was assessed in a community sample of 97 healthy mothers using the Postpartum Bonding Questionnaire (PBQ) 6 weeks after birth of their child. Social competencies in the offspring were assessed using the Self- and Other-oriented Social Competencies (SOCOMP) at 5.5 years of age. A potential correlation between bonding and social competencies was tested using Spearman Rank Correlation. Results: Retention rate over 5.5 years was 77.23%. Lower Maternal Bonding Impairment Scores 6 weeks postnatally were positively related to childrens' social competences at 5.5 years of age. Conclusion: The present data confirm a positive and long-term influence of bonding on social skills and provide further evidence of the importance of parent child bonding for child development in general. This result should give reason to further investigate this relationship in depth, causally and at later points in time.

The neuroscience of empathy and compassion in pro-social behavior

Research in the scientific literature increasingly demonstrates that empathy consists of multiple dimensions, and that defining empathy as a single encompassing term may be imprecise. Recent calls have been made for increasing empathy as means to increase pro-social behavior. However, contradictory evidence exists that empathy may reduce pro-social behavior. This debate has sparked confusion around what is empathy, along with the value of empathy in promoting pro-social behavior. This paper will examine recent advances in affective neuroscience to better understand the construct of empathy and its relationship to pro-social behavior. Individuals' responses to affective empathy, seeing the suffering of others can result in personal distress or empathic concern, which may then subsequently affect motivation for pro-social behavior. Current research in affective neuroscience suggests that combining compassion interventions in conjunction with both affective and cognitive empathy offers the most optimal likelihood that individuals will engage in pro-social behavior.

Never too late? Quadruplets at the age of 65 years

Background

We discuss the challenges of multiple pregnancy at very advanced reproductive age.

Case presentation

We present the case of a quadruplet pregnancy at the maternal age of 65 following in-vitro fertilization (IVF) with donor eggs and sperm, involving cross-border reproductive care. All children born were at 25 weeks’ gestation and survived; however, poor neurodevelopmental outcome remains a major concern in one child.

Conclusions

The use of reproductive technology to achieve a multiple pregnancy at such an advanced post-menopausal age generated a debate on ethical, psychosocial and medical questions. We share this debate and highlight the need to reconsider international guidelines for women of advanced reproductive age.

Analytical and physiological validation of an enzyme immunoassay to measure oxytocin in dog, wolf, and human urine samples

Oxytocin (OT) promotes pro-sociality, bonding, and cooperation in a variety of species. Measuring oxytocin metabolite (OTM) concentrations in urine or saliva provides intriguing opportunities to study human and animal behaviour with minimal disturbance. However, a thorough validation of analytical methods and an assessment of the physiological significance of these measures are essential. We conducted an analytical validation of a commercial Enzyme Immunoassay (EIA; Arbor OT assay kit) to measure OTM concentrations in dog, wolf, and human urine samples. To test the assay's ability to detect changes in OTM concentrations, we administered oxytocin intranasally to 14 dogs. Assay performance with regard to parallelism was acceptable. Assay accuracy and extraction efficiency for dog and wolf samples were comparable to a previously validated assay (Enzo OT assay kit) but variation was smaller for human samples. Binding sensitivity and antibody specificity were better in the Arbor assay. Average OTM concentrations were more than twice as high as in comparable samples measured with the Enzo assay, highlighting a lack of comparability of absolute values between different assays. Changes in OTM concentrations after intranasal treatment were detected reliably. The Arbor assay met requirements of a "fit-for-purpose" validation with improvement of several parameters compared to the Enzo assay.

PCIT engagement and persistence among child welfare-involved families: Associations with harsh parenting, physiological reactivity, and social cognitive processes at intake

Parent-Child interaction therapy (PCIT) has been shown to improve positive, responsive parenting and lower risk for child maltreatment (CM), including among families who are already involved in the child welfare system. However, higher risk families show higher rates of treatment attrition, limiting effectiveness. In N = 120 child welfare families randomized to PCIT, we tested behavioral and physiological markers of parent self-regulation and socio-cognitive processes assessed at pre-intervention as predictors of retention in PCIT. Results of multinomial logistic regressions indicate that parents who declined treatment displayed more negative parenting, greater perceptions of child responsibility and control in adult-child transactions, respiratory sinus arrhythmia (RSA) increases to a positive dyadic interaction task, and RSA withdrawal to a challenging, dyadic toy clean-up task. Increased odds of dropout during PCIT's child-directed interaction phase were associated with greater parent attentional bias to angry facial cues on an emotional go/no-go task. Hostile attributions about one's child predicted risk for dropout during the parent-directed interaction phase, and readiness for change scores predicted higher odds of treatment completion. Implications for intervening with child welfare-involved families are discussed along with study limitations.

Maternal deprivation during early infancy in rats increases oxytocin immunoreactivity in females and corticosterone reactivity to a social test in both sexes without changing emotional behaviour

Impairment of social behaviour is a hallmark of emotional disorders, with increased avoidance of social contact. In rats, the 24 h maternal deprivation (DEP) paradigm is used to understand the impact of extreme neglect on neurodevelopment. Due to the distinct immediate effects of DEP on postnatal days (PND) 3 (DEP3) or 11 (DEP11), in the present study we investigated the long-term effects of DEP at these ages on anxiety-like behaviour, by recording the visits and time spent in the centre part of the open-field, social investigation of a confined, same-sex, unfamiliar animal, basal and post-social test corticosterone plasma levels and the immunoreactivity to oxytocin in the paraventricular (PVN) and supraoptic nuclei of the hypothalamus (SON). Whole litters were distributed into control (CTL), DEP3 or DEP11 groups and behavioural tests and biological samples were collected between PNDs 40 and 45 in males and females. There were no differences in the exploration of the central part of the open field or on the time investigating the unfamiliar rat. However, the percent increase in post-test corticosterone secretion from baseline was greater for both DEP3 male and female subgroups than their CTL and DEP11 counterparts. DEP3 females showed more oxytocin staining than DEP11 counterparts in magnocellular neurons of the SON and PVN. These results suggest that DEP at the ages chosen does not alter social investigation, although it results in distinct neurobiological outcomes, depending on the developmental phase when it is imposed.

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.

How developmental neuroscience can help address the problem of child poverty

Nearly 1 in 5 children in the United States lives in a household whose income is below the official federal poverty line, and more than 40% of children live in poor or near-poor households. Research on the effects of poverty on children's development has been a focus of study for many decades and is now increasing as we accumulate more evidence about the implications of poverty. The American Academy of Pediatrics recently added "Poverty and Child Health" to its Agenda for Children to recognize what has now been established as broad and enduring effects of poverty on child development. A recent addition to the field has been the application of neuroscience-based methods. Various techniques including neuroimaging, neuroendocrinology, cognitive psychophysiology, and epigenetics are beginning to document ways in which early experiences of living in poverty affect infant brain development. We discuss whether there are truly worthwhile reasons for adding neuroscience and related biological methods to study child poverty, and how might these perspectives help guide developmentally based and targeted interventions and policies for these children and their families.

What can we learn from PWS and SNORD116 genes about the pathophysiology of addictive disorders?

Addictive disorders have been much investigated and many studies have underlined the role of environmental factors such as social interaction in the vulnerability to and maintenance of addictive behaviors. Research on addiction pathophysiology now suggests that certain behavioral disorders are addictive, one example being food addiction. Yet, despite the growing body of knowledge on addiction, it is still unknown why only some of the individuals exposed to a drug become addicted to it. This observation has prompted the consideration of genetic heritage, neurodevelopmental trajectories, and gene-environment interactions in addiction vulnerability. Prader-Willi syndrome (PWS) is a rare neurodevelopmental disorder in which children become addicted to food and show early social impairment. PWS is caused by the deficiency of imprinted genes located on the 15q11-q13 chromosome. Among them, the SNORD116 gene was identified as the minimal gene responsible for the PWS phenotype. Several studies have also indicated the role of the Snord116 gene in animal and cellular models to explain PWS pathophysiology and phenotype (including social impairment and food addiction). We thus present here the evidence suggesting the potential involvement of the SNORD116 gene in addictive disorders.

Association Between Accumulation of Child Maltreatment and Salivary Oxytocin Level Among Japanese Adolescents

Background: Child maltreatment is related to oxytocin (OT), which is related to social functioning. It may hamper the OT level to avoid a harmful situation and increase the OT level to adapt to the situation using a tend-and-befriend stress reaction. Objective: This study aims to examine the association between the accumulation of moderate-severe childhood maltreatment and salivary OT levels in Japanese adolescents. Participants: We used convenience samples of adolescents living in an institution (n = 31) and those living with their parents (n = 46). Methods: Child maltreatment experiences were measured with the Childhood Trauma Questionnaire. The salivary OT levels were assessed by enzyme linked immunosorbent assay. A multivariate regression analysis was performed to see the association between the accumulation of child maltreatment types and the salivary OT levels adjusted for covariates (i.e., age, sex, and duration of institutionalization). Results: Physical abuse was associated with higher OT, while emotional neglect showed an inverse association with OT. OT was the lowest with one maltreatment type group, which was significantly lower than the non-maltreatment group. As the number of maltreatment types increased from one maltreatment type to 2-3 types and to 4-5 types, OT also increased. This U-shaped association between the number of maltreatment types and OT was confirmed with the significant result of a square term of number of maltreatment type in the model (p = 0.012). Conclusion: We found herein a U-shaped association between the accumulation of child maltreatment and salivary OT levels. Also, different types of maltreatment had varied effects on the salivary OT. Further study is needed to elucidate the non-linear association between child maltreatment and OT levels.

Birth signalling hormones and the developmental consequences of caesarean delivery

Rates of delivery by caesarean section (CS) are increasing around the globe and, although several epidemiological associations have already been observed between CS and health outcomes in later life, more are sure to be discovered as this practice continues to gain popularity. The components of vaginal delivery that protect offspring from the negative consequences of CS delivery in later life are currently unknown, although much attention to date has focused on differences in microbial colonisation. Here, we present the case that differing hormonal experiences at birth may also contribute to the neurodevelopmental consequences of CS delivery. Levels of each of the 'birth signalling hormones' (oxytocin, arginine vasopressin, epinephrine, norepinephrine and the glucocorticoids) are lower following CS compared to vaginal delivery, and there is substantial evidence for each that manipulations in early life results in long-term neurodevelopmental consequences. We draw from the research traditions of neuroendocrinology and developmental psychobiology to suggest that the perinatal period is a sensitive period, during which hormones achieve organisational effects. Furthermore, there is much to be learned from research on developmental programming by early-life stress that may inform research on CS, as a result of shared neuroendocrine mechanisms at work. We compare and contrast the effects of early-life stress with those of CS delivery and propose new avenues of research based on the links between the two bodies of literature. The research conducted to date suggests that the differences in hormone signalling seen in CS neonates may produce long-term neurodevelopmental consequences.

Intranasal oxytocin administration facilitates the induction of long-term potentiation and promotes cognitive performance of maternally separated rats

Maternal separation (MS) is known to induce permanent changes in the central nervous system and is associated with increased levels of anxiety and cognitive impairments. The neuropeptide oxytocin (OT) has been implicated in a broad spectrum of social and nonsocial and behaviors. Since it plays a significant role in learning and memory and enhances synaptic plasticity, we hypothesized that OT may affect MS-induced changes in synaptic plasticity and cognitive performance. Rat pups underwent MS protocol for 180 min/day from postnatal day (PND) 1-21. OT was administered intranasally (2 μg/μl, 7 days) to control and MS groups from PND 22-34. Plasma corticosterone (CORT) levels, anxiety-like behavior, sociability, learning and memory were measured in adolescent rats. In addition, extracellular evoked field excitatory postsynaptic potentials (fEPSP) were also recorded from hippocampal slices. MS induced higher plasma CORT levels and impaired social interaction, learning and memory. Moreover, MS reduced locomotor activity and increased anxiety-like behavior. Intranasal OT could overcome MS-induced deficits and promoted sociability, learning and memory of MS rats. OT also enhanced locomotor activity in the open field and decreased anxiety-like behavior. Obtained results showed that long term potentiation (LTP) was not induced in MS animals. However, OT injection overcame the MS-induced impairment in LTP generation in CA1 area of the hippocampus.

Maximizing research on the adverse effects of child poverty through consensus measures

A variety of new research approaches are providing new ways to better understand the developmental mechanisms through which poverty affects children's development. However, studies of child poverty often characterize samples using different markers of poverty, making it difficult to contrast and reconcile findings across studies. Ideally, scientists can maximize the benefits of multiple disciplinary approaches if data from different kinds of studies can be directly compared and linked. Here, we suggest that individual studies can increase their potential usefulness by including a small set of common key variables to assess socioeconomic status and family income. These common variables can be used to (a) make direct comparisons between studies and (b) better enable diversity of subjects and aggregation of data regarding many facets of poverty that would be difficult within any single study. If kept brief, these items can be easily balanced with the need for investigators to creatively address the research questions in their specific study designs. To advance this goal, we identify a small set of brief, low-burden consensus measures that researchers could include in their studies to increase cross-study data compatibility. These US based measures can be adopted for global contexts.

Comparative study of the volume of the temporal lobe sections and neuropeptide effect in Alzheimer's patients and healthy persons

AIM

The aim of this study was to make a volumetric comparison of some medial temporal lobe structures and neuropeptides between the patients of Alzheimer's disease (AD) and healthy individuals.

METHOD

The study comprised of a group of patients diagnosed with mild AD (n:15) and a Control group (n:15) (16 females, 14 males, mean age:72.90 ± 4.50). Voxel-based morphometry and MRICloud analyses were performed on the MR images taken in 3D measurements of gray matter volumes of all subjects. Following a 10-minute hug test, blood samples were taken from all participants for oxytocin (OT) and arginine vasopressin (AVP) analyses.

RESULTS

The patient group had a statistically lower right hippocampus volume (p = 0.004) and OT values (p = 0.028) than the Control group. OT signal values increased with a volume increase in the right parahippocampal gyrus (PHG_R), and OT conc. and AVP conc. values increased with increasing volume of the PHG_R.

CONCLUSION

It is suggested that the right hippocampus, right fusiform gyrus, left amygdala, left parahippocampal gyrus, and left entorhinal cortex atrophies can be used as predictors in the early diagnosis of AD. The positive correlation between PHG_R and neuropeptides showed the need to investigate the PHG and OT function more deeply.

Endocrinological Abnormalities in Autism

A number of chemical messengers, such as various hormones and hormone-like substances, along with neurotransmitters, such as serotonin, dopamine, and norepinephrine, are directly or indirectly linked with the encoding of social behavior via their action at the amygdala, hippocampus, and other related brain structures known to be involved in different aspects of social development. It is thought that any imbalance in the secretion and action of these chemicals may lead to defective or abnormal social behaviors that are the hallmarks of Autism Spectrum Disorders (ASDs). Many of the studies have described an association between ASDs and endocrine dysfunction, but have failed to establish a cause-effect connection between these 2 conditions. All together, the literature regarding the role of endocrine-related factors and ASDs is sparse and remains somewhat preliminary, controversial, and inconclusive. Thus, more research is needed in the future to shed more light on this topic.

Revisiting the roots of attachment: A review of the biological and psychological effects of maternal skin-to-skin contact and carrying of full-term infants

During the early period of hypothesis building and empirical testing of attachment theory, a major emphasis was placed on mother-infant physical contact. In spite of this, mother-infant contact has received scant attention amongst attachment and child development researchers in the past decades. Here, a brief theoretical framework for mother-infant contact is presented, drawing on animal studies as well as human studies of preterm infants and neonates. Salient mechanisms may include an extended sensitive period during early infancy, requiring specific somatosensory stimuli for bio-behavioral homeorhesis; oxytocinergic and epigenetic pathways; kinesthetic stimuli and face-to-face proximity allowing for increased social interaction. Studies of extended human mother-full-term infant physical contact have demonstrated positive effects in multiple domains. For infants, these include sleep organization, temperature and heart rate regulation, behavioral response, crying/colic, socio-emotional development, attachment quality, speech development opportunities and mother-child interactions. For mothers, studies demonstrate improved depressive symptomatology, physiological stress regulation, contingent responsivity, breastfeeding and mother-child interactions. Parent-infant attachment quality has gained prominence as a trauma-resilience factor as well as a predictor of adult physical health. The potential role of mother-infant contact as an attachment promoting intervention as well as future research subjects are discussed. Current evidence supports the original attachment research that early maternal touch provision may influence infant socio-emotional development and attachment quality, with positive implications for mother-child relationship functioning.

Is there evidence for sensitive periods in emotional development?

During sensitive periods an individual's development is especially receptive to information from the environment in ways that it is not at earlier and later developmental stages. Here, we describe challenges in applying the concept of sensitive periods to the domain of socio-emotional development, review what applications of this approach have accomplished, and point to promising future directions. We also argue that since emotional development consists of higher-order cognitive processes, it likely involves multiple and overlapping sensitive periods tied to different mechanisms (e.g., facial recognition, reward processing, fear conditioning). Moreover, we note a distinction between the construct of a sensitive period versus the identification of an effect of early experience-two ideas that are often confused in the literature. Progress in the study of emotion will require understanding the mechanisms involved in developmental change and models that predict children's behavior based on their prior experience.

Development of Social Attention and Oxytocin Levels in Maltreated Children

Child maltreatment (CM) is a major risk factor for various psychopathologies but also adversely affects social development. Research on oxytocin (OT) is currently drawing attention as an endocrine basis for social development. In this study, we investigated the relationship between visual attention to social cues and salivary OT levels in children exposed to CM. The results revealed that the CM group had a significantly lower percentage of gaze fixation for the human face eye area and lower salivary OT levels compared to the typical development group. Moreover, a path analysis suggested that gaze fixation for the eye area was a mediator of the relationship between salivary OT levels and social-emotional problems in the CM group. These results suggest that lower endogenous OT levels in maltreated children may lead to atypical development of their visual attention to eyes as a social cue, resulting in social-emotional problems.

Human attachment triggers different social buffering mechanisms under high and low early life stress rearing

Social buffering - the attenuation of stress by maternal safety signals - is a core mammalian-general stress management mechanism implicating two ancient systems: the oxytocinergic and HPA systems. Yet, because human attachments are representation-based, understanding social buffering mechanisms in humans requires the assessment of relationship history and consideration of early life stress (ELS), which alters stress responsivity. We followed a unique trauma-exposed cohort across childhood, versus a low-stress control group, and repeatedly observed maternal sensitive, safety-promoting style. In adolescence, we used an attachment induction paradigm that exposed children to both live and reminders of attachment safety signals and measured oxytocin and cortisol baseline and response, to test how maternal safety signals impact hormonal reactivity in children reared under high- versus low-stress conditions. Only safety-promoting mothers exhibited a stress-buffering function, but their effect was system-specific and depended on the rearing context. For oxytocin, safety-promoting mothers normalized the deficient baseline oxytocin levels observed in ELS youth by implicating a plasticity-by-affiliation mechanism. For cortisol, safety-promoting mothering reduced the initial stress response only among youth reared in low-stress contexts via the typical buffering-by-safety mechanism. Results suggest that human attachments require internalized security evolving over time to trigger a stress buffering function. Under conditions of chronic early stress, the stressful rearing context overrides the maternal safety signals, normative stress buffering mechanisms fail, and safety-promoting mothers switch to an immature, affiliation-based mechanism that relies on maternal presence.

Microglial Function in the Effects of Early-Life Stress on Brain and Behavioral Development

The putative effects of early-life stress (ELS) on later behavior and neurobiology have been widely investigated. Recently, microglia have been implicated in mediating some of the effects of ELS on behavior. In this review, findings from preclinical and clinical literature with a specific focus on microglial alterations induced by the exposure to ELS (i.e., exposure to behavioral stressors or environmental agents and infection) are summarized. These studies were utilized to interpret changes in developmental trajectories based on the time at which the stress occurred, as well as the paradigm used. ELS and microglial alterations were found to be associated with a wide array of deficits including cognitive performance, memory, reward processing, and processing of social stimuli. Four general conclusions emerged: (1) ELS interferes with microglial developmental programs, including their proliferation and death and their phagocytic activity; (2) this can affect neuronal and non-neuronal developmental processes, which are dynamic during development and for which microglial activity is instrumental; (3) the effects are extremely dependent on the time point at which the investigation is carried out; and (4) both pre- and postnatal ELS can prime microglial reactivity, indicating a long-lasting alteration, which has been implicated in behavioral abnormalities later in life.

Oxytocin Response Following Playful Mother-Child Interaction in Survivors of the Great East Japan Earthquake

BACKGROUND

Children who are exposed to natural disasters are at greater risk of developing mental and behavior problems. Prior studies have suggested that positive parenting practices could prevent child mental and behavior problems among those who were exposed to natural disasters. Parent-child interaction increases oxytocin level in parents and infants; however, studies assessing the change in oxytocin level after positive parent-child interaction and its effect on child behavior problems among preadolescents who were exposed to natural disasters are lacking. This study investigated whether playful interaction stimulated oxytocin levels in 34 mother-child dyads who experienced the 2011 Great East Japan Earthquake in Kesennuma City in Miyagi Prefecture, Japan, and the effect of the maternal oxytocin changes on child behavior problems.

METHODS

Participants were recruited in 2012 after the Great East Japan Earthquake. Annual surveys were conducted from 2012 to 2017. Salivary oxytocin level was assessed before and after the playful interaction in 2015. Behavior problems were evaluated by caregivers, using the Child Behavior Checklist (CBCL) in 2017. Fixed effect regression analyses were conducted to determine the effect of playful mother-child interaction on oxytocin level by comparing the change in the 10 min after the interaction with the change in the 10 min before the interaction. We also examined the effect of maternal oxytocin changes before and after the playful interaction on the onset of child behavior problems in 2017.

RESULTS

A significant increase in maternal oxytocin level was detected following playful interaction, especially among mothers of first-born boys (2.63 pg/mg protein. 95% CI: 0.45, 4.81). Maternal psychological distress and trauma were also negatively associated with an increase of oxytocin levels. The increase in maternal oxytocin level was significantly associated with lower externalizing problem score of children 2 years later.

CONCLUSION

Our results might suggest a rational for potential preventive intervention for child behavior problems through playful mother-child interaction after natural disasters.

Study Protocol: The Coaching Alternative Parenting Strategies (CAPS) Study of Parent-Child Interaction Therapy in Child Welfare Families

BACKGROUND

Child maltreatment (CM) constitutes a serious public health problem in the United States with parents implicated in a majority of physical abuse and neglect cases. Parent-Child Interaction Therapy (PCIT) is an intensive intervention for CM families that uses innovative "bug-in-ear" coaching to improve parenting and child outcomes, and reduce CM recidivism; however, the mechanisms underlying its effects are little understood. The Coaching Alternative Parenting Strategies (CAPS) study aims to clarify the behavioral, neural, and physiological mechanisms of action in PCIT that support positive changes in parenting, improve parent and child self-regulation and social perceptions, and reduce CM in child welfare-involved families.

METHODS

The CAPS study includes 204 child welfare-involved parent-child dyads recruited from Oregon Department of Human Services to participate in a randomized controlled trial of PCIT versus a services-as-usual control condition (clinicaltrials.gov, NCT02684903). Children ages 3-8 years at study entry and their parents complete a pre-treatment assessment prior to randomization and a post-treatment assessment 9-12 months post study entry. Dyads randomized to PCIT complete an additional, abbreviated assessment at mid-treatment. Each assessment includes individual and joint measures of parents' and children's cardiac physiology at rest, during experimental tasks, and in recovery; observational coding of parent-child interactions; and individual electroencephalogram (EEG) sessions including attentional and cognitive control tasks. In addition, parents and children complete an emotion regulation task and parents report on their own and their child's adverse childhood experiences and socio-cognitive processes, while children complete a cognitive screen and a behavioral measure of inhibitory control. Parents and children also provide anthropometric measures of allostatic load and 4-5 whole blood spots to assess inflammation and immune markers. CM recidivism is assessed for all study families at 6-month follow-up. Post-treatment and follow-up assessments are currently underway.

DISCUSSION

Knowledge gained from this study will clarify PCIT effects on neurobehavioral target mechanisms of change in predicting CM risk reduction, positive, responsive parenting, and children's outcomes. This knowledge can help to guide efforts to tailor and adapt PCIT to vary in dosage and cost on the basis of individual differences in CM-risk factors.