Genetic differential susceptibility to the effects of parenting

Interaction between Risk Single-Nucleotide Polymorphisms of Developmental Dyslexia and Parental Education on Reading Ability: Evidence for Differential Susceptibility Theory

While genetic and environmental factors have been shown as predictors of children's reading ability, the interaction effects of identified genetic risk susceptibility and the specified environment for reading ability have rarely been investigated. The current study assessed potential gene-environment (G×E) interactions on reading ability in 1477 school-aged children. The gene-environment interactions on character recognition were investigated by an exploratory analysis between the risk single-nucleotide polymorphisms (SNPs), which were discovered by previous genome-wide association studies of developmental dyslexia (DD), and parental education (PE). The re-parameterized regression analysis suggested that this G×E interaction conformed to the strong differential susceptibility model. The results showed that rs281238 exhibits a significant interaction with PE on character recognition. Children with the "T" genotype profited from high PE, whereas they performed worse in low PE environments, but "CC" genotype children were not malleable in different PE environments. This study provided initial evidence for how the significant SNPs in developmental dyslexia GWA studies affect children's reading performance by interacting with the environmental factor of parental education.

Joint Roles of Oxytocin- and Dopamine-Related Genes and Childhood Parenting Experience in Maternal Supportive Social Network

How genes and parenting determine maternal social support availability, an important preventive factor of postpartum depression, has been little studied. Our study aimed to examine the interaction effects of maternal sociality-related gene and parenting on maternal social support. We analyzed data of 115 triads of Japanese grandmothers, mothers, and their infants. An interaction between parenting and cumulative genetic risk, calculated on the sociality-related genes (OXTR rs53576, rs2254298, rs1042778; COMT rs4680), was found. Mothers with high genetic risk received less social support if received poorer parenting (B = - 0.02, 95%CI = - 0.04 to - 0.01), while no association among low-risk mothers. Poorer social support was associated with severer depression in high-risk mothers (B = - 0.88, 95%CI = - 1.45 to -0.30). Our results suggest that mothers carrying risk alleles of sociality-related genes are particularly sensitive to childhood parenting, underscoring the importance of childhood parenting and genetic risk to understand maternal help-seeking behavior.

Effects of prenatal psychosocial stress and COVID-19 infection on infant attention and socioemotional development

BACKGROUND

The COVID-19 pandemic dramatically altered the psychosocial environment of pregnant women and new mothers. In addition, prenatal infection is a known risk factor for altered fetal development. Here we examine joint effects of maternal psychosocial stress and COVID-19 infection during pregnancy on infant attention at 6 months postpartum.

METHOD

One-hundred and sixty-seven pregnant mothers and infants (40% non-White; n = 71 females) were recruited in New York City (n = 50 COVID+, n = 117 COVID-). Infants' attentional processing was assessed at 6 months, and socioemotional function and neurodevelopmental risk were evaluated at 12 months.

RESULTS

Maternal psychosocial stress and COVID-19 infection during pregnancy jointly predicted infant attention at 6 months. In mothers reporting positive COVID-19 infection, higher prenatal psychosocial stress was associated with lower infant attention at 6 months. Exploratory analyses indicated that infant attention in turn predicted socioemotional function and neurodevelopmental risk at 12 months.

CONCLUSIONS

These data suggest that maternal psychosocial stress and COVID-19 infection during pregnancy may have joint effects on infant attention at 6 months. This work adds to a growing literature on the effects of the COVID-19 pandemic on infant development, and may point to maternal psychosocial stress as an important target for intervention.

IMPACT

This study found that elevated maternal psychosocial stress and COVID-19 infection during pregnancy jointly predicted lower infant attention scores at 6 months, which is a known marker of risk for neurodevelopmental disorder. In turn, infant attention predicted socioemotional function and risk for neurodevelopmental disorder at 12 months. These data suggest that maternal psychosocial stress may modulate the effects of gestational infection on neurodevelopment and highlight malleable targets for intervention.

Love on the developing brain: Maternal sensitivity and infants' neural responses to emotion in the dorsolateral prefrontal cortex

Infancy is a sensitive period of development, during which experiences of parental care are particularly important for shaping the developing brain. In a longitudinal study of N = 95 mothers and infants, we examined links between caregiving behavior (maternal sensitivity observed during a mother-infant free-play) and infants' neural response to emotion (happy, angry, and fearful faces) at 5 and 7 months of age. Neural activity was assessed using functional Near-Infrared Spectroscopy (fNIRS) in the dorsolateral prefrontal cortex (dlPFC), a region involved in cognitive control and emotion regulation. Maternal sensitivity was positively correlated with infants' neural responses to happy faces in the bilateral dlPFC and was associated with relative increases in such responses from 5 to 7 months. Multilevel analyses revealed caregiving-related individual differences in infants' neural responses to happy compared to fearful faces in the bilateral dlPFC, as well as other brain regions. We suggest that variability in dlPFC responses to emotion in the developing brain may be one correlate of early experiences of caregiving, with implications for social-emotional functioning and self-regulation.

Investigating sensitivity through the lens of parents: validation of the parent-report version of the Highly Sensitive Child scale

Children differ in their environmental sensitivity (ES), which can be measured observationally or by self-report questionnaire. A parent-report scale represents an important tool for investigating ES in younger children but has to be psychometrically robust and valid. In the current multistudy, we validated the parent-report version of the Highly Sensitive Child (HSC-PR) scale in Italian children, evaluating its factorial structure (Study 1, N = 1,857, 6.2 years, age range: 2.6-14 years) through a multigroup Confirmatory Factory Analysis in preschoolers (n = 1,066, 4.2 years) and school-age children (n = 791, 8.8 years). We then investigated the HSC-PR relationship with established temperament traits (Study 2, N = 327, 4.3 years), before exploring whether the scale moderates the effects of parenting stress on children's emotion regulation (Study 3, N = 112, 6.5 years). We found support for a bi-factor structure in both groups, though in preschoolers minor adaptations were suggested for one item. Importantly, the HSC-PR did not fully overlap with common temperament traits and moderated the effects of parenting stress on children emotion regulation. To conclude, the HSC-PR performs well and appears to capture ES in children.

Mother-infant interaction and maternal postnatal psychological distress are associated with negative emotional reactivity among infants and toddlers- A FinnBrain Birth Cohort study

Studies have reported mixed findings regarding the effects of mother-infant interaction and maternal distress on children's negative emotional reactivity. In the current study (N = 134 and 107), we examined the effects of maternal Emotional Availability (sensitivity, structuring, non-intrusiveness and non-hostility) and maternal psychological distress on negative reactivity among children in the FinnBrain birth cohort study. In addition, the possible moderating effect of mother-infant interaction on the associations between maternal psychological distress and children's negative reactivity was examined. We used questionnaires to asses maternal psychological distress, observations of mother-infant interaction and observations as well maternal reports of child temperament to overcome the key limitations of many studies relying on single-method assessments. Our results showed that higher maternal sensitivity and structuring at 8 months of child's age were associated with lower mother-reported negative reactivity among children at 24 months. Higher maternal postnatal distress associated with higher parent-reported negative reactivity in children at 12 and 24 months of age when the effects of prenatal distress and the quality of mother-infant interaction were controlled for. Mother-infant interaction and maternal psychological distress did not associate with observations of child negative reactivity. We found no moderation effects of mother-infant interaction regarding the associations between maternal distress and children's negative emotional reactivity. Our findings reflect the importance of developing interventions to reduce the maternal distress symptoms while enhancing maternal sensitivity and structuring to prevent the possible harmful effects of these on child negative reactivity.

Prenatal maternal stress, child internalizing and externalizing symptoms, and the moderating role of parenting: findings from the Norwegian mother, father, and child cohort study

BACKGROUND

Few studies have examined how parenting influences the associations between prenatal maternal stress and children's mental health. The objectives of this study were to examine the sex-specific associations between prenatal maternal stress and child internalizing and externalizing symptoms, and to assess the moderating effects of parenting behaviors on these associations.

METHODS

This study is based on 15 963 mother-child dyads from the Norwegian Mother, Father, and Child Cohort Study (MoBa). A broad measure of prenatal maternal stress was constructed using 41 self-reported items measured during pregnancy. Three parenting behaviors (positive parenting, inconsistent discipline, and positive involvement) were assessed by maternal report at child age 5 years. Child symptoms of internalizing and externalizing disorders (depression, anxiety, attention-deficit hyperactivity disorder, conduct disorder, and oppositional-defiant disorder) were assessed by maternal report at age 8. Analyses were conducted using structural equation modeling techniques.

RESULTS

Prenatal maternal stress was associated with child internalizing and externalizing symptoms at age 8; associations with externalizing symptoms differed by sex. Associations between prenatal maternal stress and child depression, and conduct disorder and oppositional-defiant disorder in males, became stronger as levels of inconsistent discipline increased. Associations between prenatal maternal stress and symptoms of attention-deficit hyperactivity disorder in females were attenuated as levels of parental involvement increased.

CONCLUSIONS

This study confirms associations between prenatal maternal stress and children's mental health outcomes, and demonstrates that these associations may be modified by parenting behaviors. Parenting may represent an important intervention target for improving mental health outcomes in children exposed to prenatal stress.

In defense of unresolved attachment: re-modelling intergenerational transmission of attachment

Intergenerational transmission of attachment is one of the core hypotheses of attachment theory. How parents or other caregivers look back on their childhood attachment experiences is suggested to shape their infants' attachments. In the current paper, we show that a new twist to correspondence analysis (Canonical Correlation Analysis [CCA]) of cross-tabulated attachment classifications with oblique rotation Correspondence Analysis (CA) may uncover the latent structure of intergenerational transmission showing the unique role of parental Unresolved representations in predicting infant Disorganized attachments. Our model of intergenerational transmission of attachment supports predicted associations between parental and infant attachments. Despite growing skepticism about the validity of parental Unresolved trauma and infant Disorganized attachment, we come to an evidence-based statistical defense of these generative clinical components of attachment theory awaiting a substantive experimentum crucis.

Beyond orchids and dandelions: Susceptibility to environmental influences is not bimodal

This study focused on generality versus specificity of susceptibility of effects of eight family and child-care exposures measured between 3 and 54 months of age (e.g., sensitive parenting, child-care quality) on five child development outcomes assessed at age 4.5 years (e.g. behavior problems, preacademic skill), using data from The National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and Youth Development (n = 1,364, boys = 705; White = 1,097, Black = 176, other = 91), while applying a novel influence-statistics method. Results indicated that susceptibility across the environment-predictor:child-outcome associations is normally rather than bimodally (i.e., orchid-dandelion) distributed. Analysis of susceptibility documents both domain generality and specificity of developmental plasticity, with effect sizes proving small in the former case. As predicted, children who as infants had difficult temperaments or who scored higher on a polygenic-plasticity score (serotonin-transporter-linked promoter region [5-HTTLPR], dopamine receptor D4 [DRD4], brain-derived neurotrophic factor [BDNF]) proved somewhat more susceptible to some of the environmental effects investigated. Results lead to the recommendation that two-types-of-individuals vis-a-vis susceptibility to environmental influences be questioned and general-trait conceptions of susceptibility be further investigated.

Early pathways of maternal mentalization: Associations with child development in the FinnBrain birth cohort study

Parental mentalization refers to a parents' capacity and interest to consider the individual experience and mental state underlying the behaviors of the child. Higher mentalization is considered a key aspect for parental sensitivity in interaction, fostering child's socioemotional and self-regulatory development. Yet, previous studies have not examined the dynamic pathways through which the maternal mentalization may develop, nor their effects on child development. Thus, in the current person-oriented study, first, we identify distinct profiles and longitudinal trajectories of maternal mentalization from pregnancy to child's 2 years of age. Second, we test how the profiles and trajectories associate with children's internalizing and externalizing problems, social-emotional competence and effortful control at the age of 2 years. Third, we examine how the profiles and trajectories associate with contextual demographic and child related. The substudy was part of the FinnBrain Birth Cohort and included families from general population (n = 2,687). Mothers reported their parental reflective functioning (PRF) at late pregnancy, 6 months and 2 years of child's age. Both mothers (n = 1,437) and fathers (n = 715) reported the developmental child outcomes at the child's age of 2 years. Latent Profile Analysis and Latent Transition Analysis were used to identify PRF profiles and trajectories. The results showed decreasing heterogeneity in PRF from pregnancy to child's age of 6 months and 2 years (i.e., four, three and two latent classes, respectively). Most mothers progressed towards high PRF over time. Second, the profiles and trajectories depicting high PRF associated with child high social-emotional competence at the age of 2 years, yet no clear positive effects were found on child's problems and effortful control. The group of mixed PRF trajectories showed strongest association with child's internalizing and externalizing problems. Finally, there were theoretically meaningful associations between the PRF trajectories and both the contextual (e.g., parity) and child related (e.g., infant temperament) factors. This was the first study to explore the early unfolding of maternal mentalization. The results are discussed in relation with the potential mechanisms accounting for child development and with the nature and limitations of self-reported parental mentalization.

Conduct Problems and Hair Cortisol Concentrations Decrease in School-Aged Children after VIPP-SD: A Randomized Controlled Trial in Two Twin Cohorts

The Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline (VIPP-SD) is effective in increasing parental sensitivity and sensitive discipline, and aims to decrease child behavior problems. Changes in quality of parenting may be accompanied by effects on child stress levels. However, studies of VIPP-SD effects on child behavior problems have shown mixed results and there are no studies to date of the effect of the intervention on children's stress levels, as measured by hair cortisol concentration (HCC). Furthermore, differences in intervention effectiveness may be explained by differential susceptibility factors. We hypothesized that the effects of the VIPP-SD on child behavior problems might be moderated by currently available child polygenic scores of differential susceptibility (PGS-DS). In the current pre-registered trial, we randomly assigned 40% of n = 445 families with school-aged twin children to the intervention group. The VIPP-SD was successful in decreasing both children's conduct problems and HCC. Effects were not moderated by available child PGS-DS. We conclude that a brief, home-based video-feedback parenting intervention can decrease child behavior problems and affect the child's stress-related neuroendocrine system as assessed with hair cortisol. In future studies, more specific PGS-DS for externalizing behaviors should be used as well as parental PGS-DS.

From temperament and parenting to attachment: a review of the interplay of gene and environment factors in the developmental pathway to attachment

PURPOSE OF REVIEW

Attachment represents an aspect of the parent-child relationship by encapsulating behaviours and stress management strategies. Although attachment is not considered a measure of psychopathology, some attachment styles place children at higher risk for psychopathologies. The origins of attachment have historically thought to be either parenting-related variables, or temperament. More recently, there has been accumulated evidence of gene × environment interactions in attachment, temperament, and parenting. This review aims to cover shared gene × environment pathways between these variables, introduce recent relevant insights from prenatal programming research, and offer a synthesized developmental cascade model of attachment.

RECENT FINDINGS

Carriers of gene polymorphisms related to stress neurobiology respond differently to environments than noncarriers according to two patterns: attachment research shows inconsistent diathesis-stress between gene polymorphisms and environment, and temperament, stress physiology, and prenatal programming research show clear patterns of differential susceptibility.

SUMMARY

By synthesizing prenatal and postnatal findings, a model of attachment emerges in which individuals more susceptible to environmental influences are carriers of specific genes, whose endophenotypic markers include stress biology and phenotypic markers include temperament. Intervention should, therefore, focus on parenting and stress regulation strategies for these individuals.

Differential Susceptibility: An Explanation for Variability in Life Course Health and Developmental Outcomes

Differential susceptibility theory posits that some individuals, with specific characteristics, are more, or less susceptible than others, to both adverse and beneficial environmental influences. It offers a perspective for understanding the directional trajectories across the life course affected by daily context and individual characteristics, in order to identify influential components. The aim of this article is to describe differential susceptibility theory, critically evaluate research findings in which the theory is tested, and consider implications of differential susceptibility theory as a theoretical framework for nursing science. Preterm birth trajectories and outcomes research are used as a lens for this examination.

Identifying Risk and Resilience Factors in the Intergenerational Cycle of Maltreatment: Results From the TRANS-GEN Study Investigating the Effects of Maternal Attachment and Social Support on Child Attachment and Cardiovascular Stress Physiology

Introduction

Childhood maltreatment (CM) is a developmental risk factor and can negatively influence later psychological functioning, health, and development in the next generation. A comprehensive understanding of the biopsychosocial underpinnings of CM transmission would allow to identify protective factors that could disrupt the intergenerational CM risk cycle. This study examined the consequences of maternal CM and the effects of psychosocial and biological resilience factors on child attachment and stress-regulatory development using a prospective trans-disciplinary approach.

Methods

Mother-child dyads (N = 158) participated shortly after parturition (t 0), after 3 months (t 1), and 12 months later (t 2). Mothers' CM experiences were assessed at t 0, attachment representation at t 1 and psychosocial risk and social support were assessed at t 1 and t 2. At t 2, dyads participated in the Strange Situation Procedure (SSP). Children's attachmen status were classified as organized vs. disorganized, including their level of disorganized behavior, and heart rate (HR) and respiratory sinus arrhythmia (RSA) were recorded as stress response measures of the autonomic nervous system. Maternal caregiving during SSP was assessed using the AMBIANCE scale. Child's single nucleotide polymorphisms rs2254298 within the oxytocin receptor (OXTR) and rs2740210 of the oxytocin gene (OXT) were genotyped using DNA isolated from cord blood.

Results

Maternal CM experiences (CM+) were significantly associated with an unresolved attachment status, higher perceived stress and more psychological symptoms. These negative effects of CM were attenuated by social support. As expected, maternal unresolved attachment and child disorganized attachment were significantly associated. Maternal caregiving did not mediate the relationship between maternal and child attachment but influenced children's HR and RSA response and disorganized behavior. Moreover, the rs2254298 genotype of the OXTR gene moderated the stress response of children from mothers with CM. Children carrying the rs2740210 risk allele of the OXT gene showed more disorganized behavior independent from maternal CM experiences.

Conclusion

We replicated and extended existing CM and attachment models by co-examining maternal attachment, social support, and child genetic susceptibility on child attachment and cardiovascular stress regulation. The findings contribute to an extended understanding of risk and resilience factors and enable professionals to target adequate services to parents and children at risk.

The human fear paradox: Affective origins of cooperative care

Already as infants humans are more fearful than our closest living primate relatives, the chimpanzees. Yet heightened fearfulness is mostly considered maladaptive, as it is thought to increase the risk of developing anxiety and depression. How can this human fear paradox be explained? The fearful ape hypothesis presented herein stipulates that, in the context of cooperative caregiving and provisioning unique to human great ape group life, heightened fearfulness was adaptive. This is because from early in ontogeny fearfulness expressed and perceived enhanced care-based responding and provisioning from, while concurrently increasing cooperation with, mothers and others. This explanation is based on a synthesis of existing research with human infants and children, demonstrating a link between fearfulness, greater sensitivity to and accuracy in detecting fear in others, and enhanced levels of cooperative behaviors. These insights critically advance current evolutionary theories of human cooperation by adding an early-developing affective component to the human cooperative makeup. Moreover, the current proposal has important cultural, societal, and health implications, as it challenges the predominant view in Western, educated, industrialized, rich, and democratic (WEIRD) societies that commonly construe fearfulness as a maladaptive trait, potentially ignoring its evolutionary adaptive functions.

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.

Oxytocin receptor genotype moderates the association between maternal prenatal stress and infant early self-regulation

INTRODUCTION

Maternal prenatal stress may have long-term adverse consequences for child development. Accumulating evidence shows that the oxytocin-receptor genotype may play a role in differential susceptibility to early-life adversity, but no studies have examined whether this moderation extends to the prenatal stress exposures.

METHODS

In the FinnBrain Birth Cohort Study, a sample of 1173 mother-child dyads were examined. We studied the possible moderating effect of the cumulative effect of infant oxytocin-receptor risk genotypes (rs53576GG and rs2254298A) in the association between maternal prenatal stress, and infant negative reactivity and emerging self-regulation at 6 months of age.

RESULTS

The number of OTr risk genotypes moderated the association between maternal prenatal anxiety and infant self-regulation, implying a cumulative effect of genotype, although effects sizes were small. In infants with two risk genotypes, a negative association between prenatal anxiety and self-regulation was observed, whereas in infants with one or no risk genotypes, the association between maternal prenatal anxiety and temperament was non-significant.

CONCLUSION

Oxytocin-receptor genotype may moderate the association of maternal stress during pregnancy and child social-emotional development. Possible mechanisms for this moderation effect are discussed. Further studies with a more comprehensive polygenic approach are needed to confirm these results.

Parental Reflective Functioning and Its Association With Parenting Behaviors in Infancy and Early Childhood: A Systematic Review

Background

Parental reflective functioning (PRF) refers to parents’ mental capacity to understand their own and their children’s behaviors in terms of envisioned mental states. As part of a broader concept of parental mentalization, PRF has been identified as one of the central predictors for sensitive parenting. However, the unique contribution of PRF to the quality of various parenting behaviors has not yet been addressed systematically. Thus, the present article provides a systematic overview of current research on the associations between PRF or its sub-dimensions and observed parenting behaviors in infancy and early childhood, while considering the influence of contextual factors.

Methods

The review was conducted following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Systematic searches were carried out in five electronic databases. The eligibility and methodological quality of the identified studies were assessed using pre-defined criteria and a standardized checklist.

Results

Sixteen studies with moderate to high quality on a total of 15 parenting behaviors were included, the majority of which examined positive parenting behaviors, while negative parenting behaviors were rarely investigated. Most of the associations indicated a positive effect of PRF on parenting behavior, with mostly small-sized effects. The strength and direction of the associations varied depending on the dimensionality of PRF, observation settings, sample types, socioeconomic factors, and cultural background. Moreover, five assessment instruments for PRF and 10 observation instruments for parenting behaviors were identified.

Conclusion

In summary, PRF has shown a positive association with parenting quality. However, its complex interaction with further contextual factors emphasizes the need for differentiation of PRF dimensions and the consideration of the observation settings, assessment time points, psychosocial risks, and sample types in observational as well as intervention studies. Further high-quality studies with multivariate analyses and diverse study settings are required.

Externalizing behavior in preschool children in a South African birth cohort: Predictive pathways in a high-risk context

Mental health problems often begin in early childhood. However, the associations of various individual and contextual risk factors with mental health in the preschool period are incompletely understood, particularly in low- to middle-income countries (LMICs) where multiple risk factors co-exist. To address this gap, we prospectively followed 981 children in a South African birth cohort, the Drakenstein Child Health Study, assessing pre-and postnatal exposures and risk factors. The predictive value of these factors for child mental health (assessed by the Child Behavior Checklist) was modeled using structural equation modeling. We identified two key pathways to greater externalizing behavior: (1) prenatal exposure to substances (alcohol and smoking) directly predicted increased externalizing behavior (β = 0.24, p < 0.001); this relationship was partially mediated by an aspect of infant temperament (negative emotionality; β = 0.05, p = 0.016); (2) lower socioeconomic status and associated maternal prenatal depression predicted more coercive parenting, which in turn predicted increased externalizing behavior (β = 0.18, p = 0.001). Findings in this high-risk LMIC cohort cohere with research from higher income contexts, and indicate the need to introduce integrated screening and intervention strategies for maternal prenatal substance use and depression, and promoting positive parenting across the preschool period.

Mentoring Children in Foster Care: Examining Relationship Histories as Moderators of Intervention Impact on Children's Mental Health and Trauma Symptoms

Mentoring-based interventions show promise among children in foster care, but previous research suggests that some benefit more than others. Because children in foster care experience relationship disruptions that could affect mentoring effectiveness, we examined whether children's relational histories at baseline (i.e., relationship quality with birth parents, relationship quality with foster parents, caregiver instability, and previous mentoring experience) moderated the impact of a mentoring intervention on children's mental health, trauma symptoms, and quality of life. Participants included 426 racially and ethnically diverse children (age: 9-11; 52% male) who participated in a randomized controlled trial of the Fostering Healthy Futures program (FHF), a 9-month one-to-one mentoring and skills group intervention. Results showed that relationship quality with foster parents and prior mentoring experience did not moderate intervention impact. Relationship quality with birth parents and caregiver instability pre-program, however, moderated the effect on some outcomes. The impact on quality of life was stronger for children with weaker birth parent relationships and fewer caregiver changes. Likewise, the impact on trauma symptoms was stronger for those with fewer caregiver changes. Overall, FHF seems to positively impact children with varied relational histories, yet some may derive more benefits - particularly those with fewer caregiver changes pre-program.

A neural model of vulnerability and resilience to stress-related disorders linked to differential susceptibility

Expert opinion remains divided concerning the impact of putative risk factors on vulnerability to depression and other stress-related disorders. A large body of literature has investigated gene by environment interactions, particularly between the serotonin transporter polymorphism (5-HTTLPR) and negative environments, on the risk for depression. However, fewer studies have simultaneously investigated the outcomes in both negative and positive environments, which could explain some of the inconclusive findings. This is embodied by the concept of differential susceptibility, i.e., the idea that certain common gene polymorphisms, prenatal factors, and traits make some individuals not only disproportionately more susceptible and responsive to negative, vulnerability-promoting environments, but also more sensitive and responsive to positive, resilience-enhancing environmental conditions. Although this concept from the field of developmental psychology is well accepted and supported by behavioral findings, it is striking that its implementation in neuropsychiatric research is limited and that underlying neural mechanisms are virtually unknown. Based on neuroimaging studies that examined how factors mediating differential susceptibility affect brain function, we posit that environmental sensitivity manifests in increased salience network activity, increased salience and default mode network connectivity, and increased salience and central executive network connectivity. These changes in network function may bring about automatic exogenous attention for positive and negative stimuli and flexible attentional set-shifting. We conclude with a call to action; unraveling the neural mechanisms through which differential susceptibility factors mediate vulnerability and resilience may lead us to personalized preventive interventions.

Gene-environment interaction: Oxytocin receptor (OXTR) polymorphisms and parenting style as potential predictors for depressive symptoms

Depression is a common mental health problem that is thought to develop through a combination of genetic, psychological, and environmental factors, including parental behaviours and parental mental health. The present study investigated the potential interaction between oxytocin receptor (OXTR) single nucleotide polymorphisms (SNPs) (rs53576, rs237880, rs237887, rs237889, rs237898, rs1042778, rs2268490, rs2268491, rs4686302, rs6770632, rs13316193) and parenting style in adolescence in relation to depressive symptoms among young adults. The sample consisted of 1,098 Caucasian participants (63.6% females) and their parents. The present study included data from the Survey of Adolescent Life Cohort study collected in 2012 at wave I (m_age 14.4 years; DNA collection), 2015 at wave II (m_age 17.36 years; Estimation of parenting style, depressive symptoms, and parental depression) and 2018 at wave III (m_age 20.19 years; Depressive symptoms). Evidence for an interaction effect between OXTR SNP rs6770632 and negative parenting style on depressive symptoms among young adults was found with support for the diathesis-stress theory. The rs6770632 was associated with depressive symptoms at higher levels of negative parenting, with A:A allele carriers reporting higher levels of depressive symptoms than C:C and C:A allele carriers. The present study provides preliminary knowledge about the potential moderation effects of perceived negative parenting on the effect of OXTR SNPs on depressive symptoms among young adults, independent of sex, previous reports of depressive symptoms, and parental depression.

Genetic differential susceptibility to the parent-child relationship quality and the life span development of compassion

The development of compassion for others might be influenced by the social experiences made during childhood and has a genetic component. No research has yet investigated whether the parent-child relationship quality interacts with genetic variation in the oxytocin and dopamine systems in predicting compassion over the life span. In the prospective Young Finns Study (N = 2099, 43.9% men), we examined the interaction between mother-reported emotional warmth and intolerance toward their child assessed in 1980 (age of participants, 3-18 years) and two established genetic risk scores for oxytocin levels and dopamine signaling activity. Dispositional compassion for others was measured with the Temperament and Character Inventory 1997, 2001, and 2012 (age of participants, 20-50 years). We found a gene-environment interaction (p = .031) that remained marginally significant after adjustment for multiple testing. In line with the differential susceptibility hypothesis, only participants who carry alleles associated with low dopamine signaling activity had higher levels of compassion when growing up with emotionally warm parents, whereas they had lower levels of compassion when their parents were emotionally cold. Children's genetic variability in the dopamine system might result in plasticity to early environmental influences that have a long-lasting effect on the development of compassion. However, our findings need replication.

Video-feedback promotes sensitive limit-setting in parents of twin preschoolers: a randomized controlled trial

BACKGROUND

Primary aim of the current randomized controlled trial was to test the effectiveness of the parenting intervention 'Video-feedback to promote Positive Parenting and Sensitive Discipline' (VIPP-SD) in a sample of parents of preschool-aged twins, as well as differential susceptibility to intervention efforts, that is, whether more temperamentally reactive parents would profit more from the VIPP-SD than parents with lower reactivity.

METHODS

The sample consisted of 202 families with same-sex twins [N = 404 children, mean age 45 months (SD = 6.81)]. Randomization was done at the family level in a 2:3 ratio, with 83 families (41%) randomized to the VIPP-SD group, and 119 families (59%) to the control group. After two pre-tests in year 1 and year 2 of the study, the VIPP-SD was implemented in the third year, with a post-test assessment 1 month after the five intervention sessions. Parental sensitivity was observed during structured play in which parent and child copied a drawing together in a computerized Etch-A-Sketch paradigm. Parental limit-setting was observed in a 'don't touch' task in which the parent required from the child to abstain from playing with attractive toys. Parents interacted with each of their twins in separate sessions.

RESULTS

The VIPP-SD intervention had a positive impact on the level of parents' positive limit-setting in interaction with their preschool twins, and this positive effect was most pronounced when the parents completed at least five intervention sessions. However, the intervention did not enhance parental sensitivity during structured play. Parents with higher reactivity were not more open to the impact of the intervention, thus for this temperamental marker differential susceptibility in adults was not supported.

CONCLUSIONS

The current study is unique in targeting families with twin preschoolers, providing proof of principle that coaching parents with video-feedback promotes parental sensitive limit-setting to both children. It remains to be seen whether this finding can be replicated in families with non-twin siblings, or other parental susceptibility markers. Trial registration Trial NL5172 (NTR5312), 2015-07-20.

Attachment-related dimensions in the epigenetic era: A systematic review of the human research

In recent years, an increasing number of studies documented potential links between parental care and epigenetic mechanisms. The present systematic review focuses on the potential association and interrelationship between attachment-related dimensions and DNA methylation in human studies. We performed a literature review using electronic databases such as PubMed, Scopus, Web of Science, and EBSCOhost. Thirteen papers were included in the review. Findings support significant associations between attachment-related dimensions and epigenetic status in studies which considered different populations, age ranges, attachment measures and peripheral tissues. Although research in this area is still under investigation, available results suggest that DNA methylation associated with attachment-related dimensions might affect the development of stress regulation system and social-emotional capacities, thus contributing to the emerging phenotypic outcomes. However, identifying mediator and moderator effects in the interrelationship between these parameters was problematic owing to heterogeneous methodologies. Finally, we discuss clinical implications, unanswered questions, and future directions for human development in epigenetics research.

Differential susceptibility 2.0: Are the same children affected by different experiences and exposures?

Differential susceptibility theory stipulates that some children are more susceptible than others to both supportive and adverse developmental experiences/exposures. What remains unclear is whether the same individuals are most affected by different exposures (i.e., domain general vs. specific). We address this issue empirically for the first time using, for illustrative and proof-of-principle purposes, a novel influence-statistics' method with data from the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care. Results indicated that previously documented effects of greater quality of care on enhanced pre-academic skills and greater quantity of care on more behavior problems apply mostly to different children. Analyses validating the new method indicated, as predicted, that (a) the quantity-of-care effect applied principally to children from more socioeconomically advantaged families and that (b) being highly susceptible to both, one or neither childcare effect varied as a function of a three-gene, polygenic-plasticity score (serotonin transporter linked polymorphic region [5-HTTLPR], dopamine receptor D4 [DRD4], brain-derived neurotrophic factor [BDNF]) in a dose-response manner (i.e., 2>1>0). While domain-specific findings involving child-care effects cannot be generalized to other environmental influences, the influence-statistics' approach appears well suited for investigating the generality-specificity of environment effects, that is, of "differential, differential susceptibility."

Description, prediction and causation: Methodological challenges of studying child and adolescent development

Scientific research can be categorized into: a) descriptive research, with the main goal to summarize characteristics of a group (or person); b) predictive research, with the main goal to forecast future outcomes that can be used for screening, selection, or monitoring; and c) explanatory research, with the main goal to understand the underlying causal mechanism, which can then be used to develop interventions. Since each goal requires different research methods in terms of design, operationalization, model building and evaluation, it should form an important basis for decisions on how to set up and execute a study. To determine the extent to which developmental research is motivated by each goal and how this aligns with the research designs that are used, we evaluated 100 publications from the Consortium on Individual Development (CID). This analysis shows that the match between research goal and research design is not always optimal. We discuss alternative techniques, which are not yet part of the developmental scientist's standard toolbox, but that may help bridge some of the lurking gaps that developmental scientists encounter between their research design and their research goal. These include unsupervised and supervised machine learning, directed acyclical graphs, Mendelian randomization, and target trials.

The PAX Good Behavior Game: One Model for Evolving a More Nurturing Society

This paper describes the culture and components of the PAX Good Behavior Game and offers it as one model for how to enhance the well-being of populations through the diffusion of nurturing practices into several venues of society. The PAX components, also known as evidence-based kernels, are proposed to be useful in classrooms, families, organizations, criminal justice, and in improving public discussion and government. Kernels affect behavior in the short- and long-term through combinations of antecedents, reinforcers, relational networks, and physiological effects. Identifying common strategies, tools, and clear targets of change is suggested as a way to work towards evolving freely available evidence-based tools that can be combined to improve social conditions in multiple contexts.

Neonatal brain volume as a marker of differential susceptibility to parenting quality and its association with neurodevelopment across early childhood

Parenting quality is associated with child cognitive and executive functions (EF), which are important predictors of social and academic development. However, children vary in their susceptibility to parenting behaviors, and the neurobiological underpinnings of this susceptibility are poorly understood. In a prospective longitudinal study, we examined whether neonatal total brain volume (TBV) and subregions of interest (i.e., hippocampus (HC) and anterior cingulate gyrus (ACG)) moderate the association between maternal sensitivity and cognitive/EF development across early childhood. Neonates underwent a brain magnetic resonance imaging scan. Their cognitive performance and EF was characterized at 2.0 ± 0.1 years (N = 53) and at 4.9 ± 0.8 years (N = 36) of age. Maternal sensitivity was coded based on observation of a standardized play situation at 6-mo postpartum. Neonatal TBV moderated the association between maternal sensitivity and 2-year working memory as well as all 5-year cognitive outcomes, suggesting that the positive association between maternal sensitivity and child cognition was observed only among children with large or average but not small TBV as neonates. Similar patterns were observed for TBV-corrected HC and ACG volumes. The findings suggest that larger neonatal TBV, HC and ACG may underlie susceptibility to the environment and affect the degree to which parenting quality shapes long-term cognitive development.

Neural and behavioral signatures of social evaluation and adaptation in childhood and adolescence: The Leiden consortium on individual development (L-CID)

The transition period between early childhood and late adolescence is characterized by pronounced changes in social competence, or the capacity for flexible social adaptation. Here, we propose that two processes, self-control and prosociality, are crucial for social adaptation following social evaluation. We present a neurobehavioral model showing commonalities in neural responses to experiences of social acceptance and rejection, and multiple pathways for responding to social context. The Leiden Consortium on Individual Development (L-CID) provides a comprehensive approach towards understanding the longitudinal developmental pathways of, and social enrichment effects on, social competence, taking into account potential differential effects of such enrichment. Using Neurosynth based brain maps we point towards the medial prefrontal cortex as an important region integrating social cognition, self-referential processing and self-control for learning to respond flexibly to changing social contexts. Based on their role in social evaluation processing, we suggest to examine medial prefrontal cortex connections with lateral prefrontal cortex and the ventral striatum as potential neural differential susceptibility markers, in addition to previously established markers of differential susceptibility.

Three phases of Gene × Environment interaction research: Theoretical assumptions underlying gene selection

Some Gene × Environment interaction (G×E) research has focused upon single candidate genes, whereas other related work has targeted multiple genes (e.g., polygenic scores). Each approach has informed efforts to identify individuals who are either especially vulnerable to the negative effects of contextual adversity (diathesis stress) or especially susceptible to both positive and negative contextual conditions (differential susceptibility). A critical step in all such molecular G×E research is the selection of genetic variants thought to moderate environmental influences, a subject that has not received a great deal of attention in critiques of G×E research (beyond the observation of small effects of individual genes). Here we conceptually distinguish three phases of G×E work based on the selection of genes presumed to moderate environmental effects and the theoretical basis of such decisions: (a) single candidate genes, (b) composited (multiple) candidate genes, and (c) GWAS-derived polygenic scores. This illustrative, not exhaustive, review makes it clear that implicit or explicit theoretical assumptions inform gene selection in ways that have not been clearly articulated or fully appreciated.

The relevance of a rodent cohort in the Consortium on Individual Development

One of the features of the Consortium on Individual Development is the existence of a rodent cohort, in parallel with the human cohorts. Here we give an overview of the current status. We first elaborate on the choice of rat and mouse models mimicking early life adverse or beneficial conditions during development. We performed a systematic literature search on early life adversity and adult social behavior to address the status quo. Next, we describe the behavioral tasks we used and designed to examine behavioral control and social competence in rodents. The results so far indicate that manipulation of the environment in the first postnatal week only subtly affects social behavior. Stronger effects were seen in the model that targeted early adolescence; once adult, these rats are characterized by increased attention, a higher degree of impulsiveness and reduced social interest in peers. Many experiments in our rodent models with tightly controlled conditions were inspired by findings in human cohorts, and now allow in-depth mechanistic investigations. Vice versa, some of the findings in rodents are currently followed up by dedicated investigations in the human cohorts. This exemplifies the added value of animal investigations in a consortium encompassing primarily human developmental cohorts.

Differential susceptibility effects of maternal sensitivity in childhood on small for gestational age adults' wealth

Being born small for gestational age (SGA) is considered a developmental vulnerability. Alternatively, SGA may be viewed as a marker for individual susceptibility to environmental experiences. The aim was to test if individuals born SGA are more susceptible to both negative and positive environmental experiences assessed by sensitive parenting in childhood compared with those born appropriate for gestational age (AGA). The target outcome was wealth in young adulthood. A total of 438 participants (SGA, n = 109; AGA, n = 329) were studied as part of the prospective Bavarian Longitudinal Study of neonatal at-risk children. Maternal sensitivity was observed during a standardized mother-child interaction task, and IQ was assessed with the Kaufman Assessment Battery for Children at age 6 years. At age 26, participants' wealth was assessed with a comprehensive composite score. Individuals born SGA were found to be more susceptible to the effects of sensitive parenting after controlling for gestational age and IQ at age 6 years. When maternal sensitivity was lower than average, SGA adults did worse than AGA adults, but when exposed to above-average maternal sensitivity in childhood, they obtained significantly higher wealth than their AGA peers by 26 years of age.

Exploring how Family and Neighborhood Stressors Influence Genetic Risk for Adolescent Conduct Problems and Alcohol Use

Previous research suggests that genetic risk factors may predispose to conduct problems and alcohol use in adolescence. Whether genetic risk factors interact with social contexts has not been well characterized among African American adolescents. Data came from a subsample of the Genes, Environment, and Neighborhood Initiative study comprising 501 African American adolescents, including 151 lifetime drinkers (56% female, mean age = 16.3, SD = 1.4). Genetic risk was assessed with polygenic risk scores for alcohol dependence. Analyses explored interactions between genetic risk and self-reported alcohol use, conduct problems, life stressors, and other covariates. The effects of two gene-environment interactions (G × E) were tested in the sample of alcohol exposed adolescents; one on conduct problems and the other on alcohol use. There were significant associations between polygenic risk for alcohol dependence and conduct problems. A significant G × E interaction showed the impact of genetic risk on conduct problems was stronger under conditions of high exposure to family and neighborhood stressors. Among this sample of African American adolescents, genetic risk for alcohol dependence was not directly associated with alcohol use but was related to more conduct problems. Further, the effect of genetic risk interacted with stressors from the family and neighborhood, so that the effect of genetic risk on conduct problems was stronger for individuals who reported greater stressors.

A learning theory of attachment: Unraveling the black box of attachment development

Attachment is an inborn behavioral system that is biologically driven and essential for survival. During child development, individual differences in (in)secure attachment emerge. The development of different attachment behaviors has been traditionally explained as a process during which experiences with (lack of) responsive and supportive care are internalized into working models of attachment. However, this idea has been criticized for being vague and even untestable. With the aim of unraveling this black box, we propose to integrate evidence from conditioning research with attachment theory to formulate a Learning Theory of Attachment. In this review, we explain how the development of individual differences in attachment security at least partly follows the principles of classical and operant conditioning. We combine observed associations between attachment and neurocognitive and endocrinological (cortisol, oxytocin, and dopamine) processes with insights in conditioning dynamics to explain the development of attachment. This may contribute to the explanation of empirical observations in attachment research that are insufficiently accounted for by traditional attachment theory.

Maternal care of heterozygous dopamine receptor D4 knockout mice: Differential susceptibility to early-life rearing conditions

The differential susceptibility hypothesis proposes that individuals who are more susceptible to the negative effects of adverse rearing conditions may also benefit more from enriched environments. Evidence derived from human experiments suggests the lower efficacy dopamine receptor D4 (DRD4) 7‐repeat as a main factor in exhibiting these for better and for worse characteristics. However, human studies lack the genetic and environmental control offered by animal experiments, complicating assessment of causal relations. To study differential susceptibility in an animal model, we exposed Drd4^+/− mice and control litter mates to a limited nesting/bedding (LN), standard nesting (SN) or communal nesting (CN) rearing environment from postnatal day (P) 2‐14. Puberty onset was examined from P24 to P36 and adult females were assessed on maternal care towards their own offspring. In both males and females, LN reared mice showed a delay in puberty onset that was partly mediated by a reduction in body weight at weaning, irrespective of Drd4 genotype. During adulthood, LN reared females exhibited characteristics of poor maternal care, whereas dams reared in CN environments showed lower rates of unpredictability towards their own offspring. Differential susceptibility was observed only for licking/grooming levels of female offspring towards their litter; LN reared Drd4^+/− mice exhibited the lowest and CN reared Drd4^+/− mice the highest levels of licking/grooming. These results indicate that both genetic and early‐environmental factors play an important role in shaping maternal care of the offspring for better and for worse.

Interactions between the combined genotypes of 5-HTTLPR and BDNF Val66Met polymorphisms and parenting on adolescent depressive symptoms: A three-year longitudinal study

BACKGROUND

The importance of multiple genes-environment interaction (G × E) has been highlighted in studies on depressive symptoms. 5-HTTLPR and BDNF Val66Met polymorphisms, with functional interconnection, have been implicated in the pathophysiology of depressive symptoms. However, little is understood about whether the interaction of 5-HTTLPR, BDNF Val66Met and parenting fits better with the epistatic or cumulative manner.

METHODS

865 adolescents (T1: M_age = 12.32, 50.2% girls) were included in a three-year interval longitudinal design. Standardized questionares about parenting and depressive symptoms were collected. Saliva samples were collected for genotyping.

RESULTS

Neither the concurrent nor longitudinal interaction of 5-HTTLPR, BDNF Val66Met and parenting (G × G × E) showed significant effects on depressive symptoms. The interaction between cumulative genotypes and positive parenting (CG × E) was significant, with the strong differential susceptibility model, for depressive symptoms concurrently but not longitudinally after statistical correction. Adolescents who carried 3 (i.e. SS and Val/Met, L allele and Val/Val) and 4 (i.e. SS and Val/Val), not 1 (i.e. L allele and Met/Met) or 2 cumulative susceptibility alleles (i.e. SS and Met/Met, L allele and Val/Met), reported fewer depressive symptoms if they had experienced higher levels of positive parenting, and more symptoms under lower levels of positive parenting.

LIMITATIONS

This study did not examine the 5-HTTLPR triallelic (rs25531) marker and did not include an external sample.

CONCLUSIONS

The combined effects of 5-HTTLPR and BDNF Val66Met polymorphisms functioned in a manner of cumulative rather than epistatic in response to positive parenting on early adolescent depressive symptoms.

Annual Research Review: Umbrella synthesis of meta-analyses on child maltreatment antecedents and interventions: differential susceptibility perspective on risk and resilience

Child maltreatment in the family context is a prevalent and pervasive phenomenon in many modern societies. The global perpetration of child abuse and neglect stands in stark contrast to its almost universal condemnation as exemplified in the United Nation's Convention on the Rights of the Child. Much work has been devoted to the task of prevention, yet a grand synthesis of the literature is missing. Focusing on two core elements of prevention, that is, antecedents for maltreatment and the effectiveness of (preventative) interventions, we performed an umbrella review of meta-analyses published between January 1, 2014, and December 17, 2018. Meta-analyses were systematically collected, assessed, and integrated following a uniform approach to allow their comparison across domains. From this analysis of thousands of studies including almost 1.5 million participants, the following risk factors were derived: parental experience of maltreatment in his or her own childhood (d = .47), low socioeconomic status of the family (d = .34), dependent and aggressive parental personality (d = .45), intimate partner violence (d = .41), and higher baseline autonomic nervous system activity (d = .24). The effect size for autonomic stress reactivity was not significant (d = -.10). The umbrella review of interventions to prevent or reduce child maltreatment showed modest intervention effectiveness (d = .23 for interventions targeting child abuse potential or families with self-reported maltreatment and d = .27 for officially reported child maltreatment cases). Despite numerous studies on child maltreatment, some large gaps in our knowledge of antecedents exist. Neurobiological antecedents should receive more research investment. Differential susceptibility theory may shed more light on questions aimed at breaking the intergenerational transmission of maltreatment and on the modest (preventive) intervention effects. In combination with family-based interaction-focused interventions, large-scale socioeconomic experiments such as cash transfer trials and experiments with vouchers to move to a lower-poverty area might be tested to prevent or reduce child maltreatment. Prevalence, antecedents, and preventive interventions of prenatal maltreatment deserve continuing scientific, clinical, and policy attention.

Attachment, culture, and gene-culture co-evolution: expanding the evolutionary toolbox of attachment theory

I argue that attachment relationships, and particularly secure ones, are important contexts for social learning and cultural transmission. Bowlby originally treated the attachment-behavioral system as serving only one evolutionary function: protection, via physical proximity. Yet the time is ripe to consider learning, especially social learning, as an additional functional consequence of attachment. Updated accordingly, attachment theory has the potential to serve as a much-needed developmental anchor for models of cultural evolution and gene-culture co-evolution. To support my arguments, I review progress in evolutionary science since Bowlby's lifetime, highlighting the growing recognition of ecological flexibility and the cultural embeddedness of animal behavior. I also review research pointing to a facilitating role of secure attachment relationships for social learning from caregivers among humans. For illustrational purposes, I show how one important aspect of human culture - religion - is culturally transmitted within attachment relationships, and of how the generalization of attachment-related working models biases the cultural transmission of religion from parents to offspring. I end the paper with a call for empirical research to test the role of attachment in cultural transmission beyond religion.

Observer-rated environmental sensitivity moderates children's response to parenting quality in early childhood

According to several developmental theories some children are more sensitive to the quality of their environment than others, but most supporting empirical evidence is based on relatively distal markers of hypothesized sensitivity. This study provides evidence for the validity of behaviorally observed Environmental Sensitivity as a moderator of parenting effects on children's early development in a sample of 292 children (Mage = 3.74; SD = 0.26) and their mothers. Sensitivity was coded using a newly developed observational measure for the specific and objective assessment of Environmental Sensitivity, the Highly Sensitive Child-Rating System (HSC-RS). HSC-RS factorial structure, associations with temperament traits, and interactions with parenting quality in the prediction of socioemotional child outcomes are reported. Findings supported a 1-factor solution. Observed sensitivity was relatively distinct from observed temperament and interacted with both low and high parenting quality in the development of behavior problems and social competence at ages 3 and 6. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Children's DAT1 Polymorphism Moderates the Relationship Between Parents' Psychological Profiles, Children's DAT Methylation, and Their Emotional/Behavioral Functioning in a Normative Sample

Parental psychopathological risk is considered as one of the most crucial features associated with epigenetic modifications in offspring, which in turn are thought to be related to their emotional/behavioral profiles. The dopamine active transporter (DAT) gene is suggested to play a significant role in affective/behavioral regulation. On the basis of the previous literature, we aimed at verifying whether children’s DAT1 polymorphisms moderated the relationship between parents’ psychological profiles, children’s emotional/behavioral functioning, and DAT1 methylation in a normative sample of 79 families with school-age children (Ntot = 237). Children’s biological samples were collected through buccal swabs, while Symptom Check-List-90 item Revised, Adult Self Report, and Child Behavior Check-List/6–18 was administered to assess parental and children’s psychological functioning. We found that higher maternal externalizing problems predicted the following: higher levels of children’s DAT1 methylation at M1, but only among children with 10/10 genotype; higher levels of methylation at M2 among children with 10/10 genotype; while lower levels for children with a 9-repeat allele. There was also a positive relationship between fathers’ externalizing problems and children’s externalizing problems, only for children with a 9-repeat allele. Our findings support emerging evidence of the complex interplay between genetic and environmental factors in shaping children’ emotional/behavioral functioning, contributing to the knowledge of risk variables for a child’s development and psychological well-being.

Association of MAOA genetic variants and resilience with psychosocial stress: A longitudinal study of Syrian refugees

Early childhood trauma can have profound and lifelong effects on adult mental health and psychosocial wellbeing. Nevertheless, responses to trauma are highly variable. Genetic variants may help explain variation in responses to trauma by identifying alleles that associate with changes in mental health measures. Protective factors, such as resilience, likely also play an important role in responses to trauma. The effects of genetic variants, in combination with protective factors, on psychosocial health are not well understood, particularly in non-Western contexts. In this study, we test the relative influence of genetic variants of monoamine oxidase A (MAOA, a gene proposed to influence the impact of childhood trauma on adult violence and antisocial behavior), levels of resilience, and exposure to traumatic events on psychosocial stress and mental health trajectories over time. We use data from a cohort of 12-18-year-old Syrian refugees who were forcibly displaced to neighboring Jordan (n = 399). DNA samples and survey data on trauma exposure, resilience (CYRM-12), and psychosocial stress were collected at three time points: baseline, ~13 weeks, and ~48 weeks. Using multilevel models, we identified an association of MAOA variant, in males only, with symptom scores of psychosocial stress on the Perceived Stress Scale (PSS) over time (p = 8.1 x 10⁻⁴). We also found that resilience is strongly associated with PSS (p = 7.9 x 10⁻⁹), underscoring the importance of protective factors in influencing levels of psychosocial stress. Furthermore, there was an additive effect wherein the sharpest reductions in perceived psychosocial stress are seen in low-activity MAOA males with low trauma exposure or high resilience levels. Our results highlight the value of studies that integrate genetic and psychosocial factors to better understand complex phenotypes, such as responses to trauma in contexts of high trauma exposure.

The effects of different rearing conditions on sexual maturation and maternal care in heterozygous mineralocorticoid receptor knockout mice

Sexual and social development is affected by a complex interplay between genetic makeup and the early-life rearing environment. While many rodent studies focused primarily on the detrimental effects of early-life stress, human literature suggests that genetic susceptibility may not be restricted to negative environments; it may also enhance the beneficial effects of positive rearing conditions. To examine this interaction in a controlled setting, heterozygous mineralocorticoid receptor knockout (MR^+/-) mice and control litter mates were exposed to a limited nesting/bedding (LN, impoverished), standard nesting (SN, control) or communal nesting (CN, enriched) paradigm from postnatal day 2-9 (P2-P9). Offspring was monitored for puberty onset between P24-P36 and, in females, maternal care-giving (i.e. as F1) during adulthood, after which basal corticosterone was measured. Different home-cage environments resulted in profound differences in received maternal care and offspring body weight. In male offspring, LN resulted in delayed puberty onset that was mediated by body weight and unpredictability of maternal care received during early development. In female offspring, rearing condition did not significantly alter sexual maturation and had little effect on their own maternal care-giving behavior. Genotype did affect maternal care: female MR^+/- offspring exhibited a less active nursing style and upregulated fragmentation during adulthood, irrespective of early life conditions. Basal corticosterone levels were highest in MR^+/- mice with a background of LN. Overall, we found a gene-by-environment interaction with respect to basal corticosterone levels, but not for sexual maturation or maternal behavior.

Neural substrates of early executive function development

In the last decade, advances in neuroimaging technologies have given rise to a large number of research studies that investigate the neural underpinnings of executive function (EF). EF has long been associated with the prefrontal cortex (PFC) and involves both a unified, general element, as well as the distinct, separable elements of working memory, inhibitory control and set shifting. We will highlight the value of utilising advances in neuroimaging techniques to uncover answers to some of the most pressing questions in the field of early EF development. First, this review will explore the development and neural substrates of each element of EF. Second, the structural, anatomical and biochemical changes that occur in the PFC during infancy and throughout childhood will be examined, in order to address the importance of these changes for the development of EF. Third, the importance of connectivity between regions of the PFC and other brain areas in EF development is reviewed. Finally, throughout this review more recent developments in neuroimaging techniques will be addressed, alongside the implications for further elucidating the neural substrates of early EF development in the future.