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.

Childhood adversity is thought to undermine youth socioemotional development via altered neural function within regions that support emotion processing. These effects are hypothesized to be developmentally specific, with adversity in early childhood sculpting subcortical structures (e.g., amygdala) and adversity during adolescence impacting later-developing structures (e.g., prefrontal cortex; PFC). However, little work has tested these theories directly in humans. Using prospectively collected longitudinal data from the Fragile Families and Child Wellbeing Study (FFCWS) (N = 4,144) and neuroimaging data from a subsample of families recruited in adolescence (N = 162), the current study investigated the trajectory of harsh parenting across childhood (i.e., ages 3 to 9) and how initial levels versus changes in harsh parenting across childhood were associated with corticolimbic activation and connectivity during socioemotional processing. Harsh parenting in early childhood (indexed by the intercept term from a linear growth curve model) was associated with less amygdala, but not PFC, reactivity to angry facial expressions. In contrast, change in harsh parenting across childhood (indexed by the slope term) was associated with less PFC, but not amygdala, activation to angry faces. Increases in, but not initial levels of, harsh parenting were also associated with stronger positive amygdala–PFC connectivity during angry face processing.

Internalizing symptoms are the most prevalent mental health problem in adolescents, with sharp increases seen, particularly for girls, and evidence that young people today report more problems than previous generations. It is therefore critical to measure and monitor these states on a large scale and consider correlates. We used novel panel network methodology to explore relationships between internalizing symptoms, well-being, and inter/intrapersonal indicators. A multiverse design was used with 32 conditions to consider the stability of results across arbitrary researcher decisions in a large community sample over three years (N = 15,843, aged 11–12 at Time 1). Networks were consistently similar for girls and boys. Stable trait-like effects within anxiety, attentional, and social indicators were found. Within-person networks were densely connected and suggested mental health and inter/intrapersonal correlates related to one another in similar complex ways. The multiverse design suggested the particular operationalization of items can substantially influence conclusions. Nevertheless, indicators such as thinking clearly, unhappiness, dealing with stress, and worry showed more consistent centrality, suggesting these indicators may play particularly important roles in the development of mental health in adolescence.

Perturbations to the gut microbiome are implicated in altered neurodevelopmental trajectories that may shape life span risk for emotion dysregulation and affective disorders. However, the sensitive periods during which the microbiome may influence neurodevelopment remain understudied. We investigated relationships between gut microbiome composition across infancy and temperament at 12 months of age. In 67 infants, we examined if gut microbiome composition assessed at 1–3 weeks, 2, 6, and 12 months of age was associated with temperament at age 12 months. Stool samples were sequenced using the 16S Illumina MiSeq platform. Temperament was assessed using the Infant Behavior Questionnaire-Revised (IBQ-R). Beta diversity at age 1–3 weeks was associated with surgency/extraversion at age 12 months. Bifidobacterium and Lachnospiraceae abundance at 1–3 weeks of age was positively associated with surgency/extraversion at age 12 months. Klebsiella abundance at 1–3 weeks was negatively associated with surgency/extraversion at 12 months. Concurrent composition was associated with negative affectivity at 12 months, including a positive association with Ruminococcus-1 and a negative association with Lactobacillus. Our findings support a relationship between gut microbiome composition and infant temperament. While exploratory due to the small sample size, these results point to early and late infancy as sensitive periods during which the gut microbiome may exert effects on neurodevelopment.

Alloparental caregiving is key to humans’ highly flexible reproductive strategies. Across species and across societies, alloparental care is more common in harsh and/or unpredictable environments (HUEs). Currently, however, it is unclear whether HUEs predict intra-population variation in alloparental care, or whether early life HUEs might predict later alloparental care use in adulthood, consistent with adaptive developmental plasticity. We test whether harshness measures (socioeconomic status (SES), environmental hygiene, crowding) and unpredictability measures (parental unemployment, paternal absence, household moves) predicted how much alloparental assistance families in Cebu, Philippines received, in a multigenerational study with data collected across four decades. Though worse environmental hygiene predicted more concurrent alloparental care in 1994, we found little evidence that HUEs predict within-population variation in alloparental care in this large-scale, industrialized society. Indeed, less-crowded conditions and higher SES predicted more alloparental care, not less, in the 1980s and in 2014 respectively, while paternal absence in middle childhood predicted less reliance on alloparental care in adulthood. In this cultural context, our results generally do not provide support for the translation of interspecific or intersocietal patterns linking HUEs and alloparental care to intra-population variation in alloparental care, nor for the idea that a reproductive strategy emphasizing alloparental care use may be preceded by early life HUEs.

Temperamental behavioral inhibition (BI) is a robust endophenotype for anxiety characterized by increased sensitivity to novelty. Controlling parenting can reinforce children's wariness by rewarding signs of distress. Fine-grained, dynamic measures are needed to better understand both how children perceive their parent's behaviors and the mechanisms supporting evident relations between parenting and socioemotional functioning. The current study examined dyadic attractor patterns (average mean durations) with state space grids, using children's attention patterns (captured via mobile eye tracking) and parental behavior (positive reinforcement, teaching, directives, intrusion), as functions of child BI and parent anxiety. Forty 5- to 7-year-old children and their primary caregivers completed a set of challenging puzzles, during which the child wore a head-mounted eye tracker. Child BI was positively correlated with proportion of parent's time spent teaching. Child age was negatively related, and parent anxiety level was positively related, to parent-focused/controlling parenting attractor strength. There was a significant interaction between parent anxiety level and child age predicting parent-focused/controlling parenting attractor strength. This study is a first step to examining the co-occurrence of parenting behavior and child attention in the context of child BI and parental anxiety levels.

The Adult Attachment Interview (AAI) is a widely used measure in developmental science that assesses adults’ current states of mind regarding early attachment-related experiences with their primary caregivers. The standard system for coding the AAI recommends classifying individuals categorically as having an autonomous, dismissing, preoccupied, or unresolved attachment state of mind. However, previous factor and taxometric analyses suggest that: (a) adults’ attachment states of mind are captured by two weakly correlated factors reflecting adults’ dismissing and preoccupied states of mind and (b) individual differences on these factors are continuously rather than categorically distributed. The current study revisited these suggestions about the latent structure of AAI scales by leveraging individual participant data from 40 studies (N = 3,218), with a particular focus on the controversial observation from prior factor analytic work that indicators of preoccupied states of mind and indicators of unresolved states of mind about loss and trauma loaded on a common factor. Confirmatory factor analyses indicated that: (a) a 2-factor model with weakly correlated dismissing and preoccupied factors and (b) a 3-factor model that further distinguished unresolved from preoccupied states of mind were both compatible with the data. The preoccupied and unresolved factors in the 3-factor model were highly correlated. Taxometric analyses suggested that individual differences in dismissing, preoccupied, and unresolved states of mind were more consistent with a continuous than a categorical model. The importance of additional tests of predictive validity of the various models is emphasized.

Self-concept refers to individuals’ perceptions of themselves in specific domains and is closely related with their overall self-esteem. Lower self-esteem has been reported in those born preterm (<37 weeks gestation), but the development of self-concept has not been studied in this population. This study investigates whether differences in trajectories of domain-specific self-concepts are explained by premature birth or other risk factors, using the Bavarian Longitudinal Study (N = 460), a population-based study of very preterm (VP; <32 weeks gestation)/very low birth weight (VLBW; <1500 g) cohort and term-born controls. Trajectories of body and social self-concept from 6 to 26 years of age were estimated using latent class growth analysis. Regression models examined the effects of VP/VLBW and other individual, social, and family factors. Two trajectories – one stable and one decreasing – were identified for both self-concepts. VP/VLBW birth was associated with decreasing self-concept in both domains, although the effect of VP/VLBW on social self-concept was weakened in the adjusted analysis. Furthermore, mediated pathways were found from VP/VLBW to decreasing social self-concept via chronic bullying (β = 0.05, 95% CI [0.002, 0.12]) and motor impairments (β = 0.04, 95% CI [0.01, 0.07]), suggesting that negative self-concept in the VP/VLBW population is partially modifiable through improving peer relationships and motor impairments in childhood.

Research on marital quality and child well-being is currently limited by its common use of geographically constrained, homogenous, and often cross-sectional (or at least temporally limited) samples. We build upon previous work showing multiple trajectories of marital quality and data from the National Longitudinal Survey of Youth-1979 (NLSY79) regarding mothers and their children (inclusive of ages 5–14). We examine how indicators of child well-being are linked to parental trajectories of marital quality (happiness, communication, and conflict). Results showed children whose parents had consistently poor marital quality over the life course exhibited more internalizing and externalizing problems, poorer health, lower quality home environments, and lower math and vocabulary scores than children of parents in consistently higher-quality marriages. Group differences remained stable over time for child health, home environment, and vocabulary scores. Group differences for internalizing problems declined over time, whereas group differences increased for externalizing problems and math scores. Initial advantages for females across nearly all indicators of child well-being tended to shrink over time, with boys often moving slightly ahead by mid adolescence. We discuss the implications of these findings in regard to children's development and well-being and suggest treating marriage as a monolithic construct betrays important variation within marriage itself.

We evaluated whether the association between deviant peer affiliation and onset of substance use is conditional upon sex and sympathetic nervous system (SNS) reactivity as measured by pre-ejection period (PEP). Community-sampled adolescents (N = 251; M = 15.78 years; 53% female; 66% White, 34% Black) participated in three waves. PEP reactivity was collected during a mirror star-tracer stress task. Alcohol, marijuana, tobacco, or any substance use, as well as binge drinking and sexual activity involving substance use were outcomes predicted by affiliation with deviant peers and two- and three-way interactions with sex and PEP reactivity. Probability of substance use increased over time, but this was amplified for adolescents with greater deviant peer affiliation in conjunction with blunted PEP reactivity. The same pattern of results was also found for prediction of binge drinking and sexual activity involving substance use. Findings are discussed in the context of biosocial models of adolescent substance use and health risk behaviors.

Acute stress affects interoception, but it remains unclear if this is due to activation of the sympatho-adreno-medullary (SAM) or hypothalamic–pituitary–adrenocortical axis. This study aimed to investigate the effect of SAM axis activation on interoceptive accuracy (IAcc). Central alpha2-adrenergic receptors represent a negative feedback mechanism of the SAM axis. Major depressive disorder and adverse childhood experiences (ACE) are associated with alterations in the biological stress systems, including central alpha2-adrenergic receptors. Here, healthy individuals with and without ACE as well as depressive patients with and without ACE (n = 114; all without antidepressant medication) were tested after yohimbine (alpha2-adrenergic antagonist) and placebo. We assessed IAcc and sensibility in a heartbeat counting task. Increases in systolic and diastolic blood pressure after yohimbine confirmed successful SAM axis activation. IAcc decreased after yohimbine only in the healthy group with ACE, but remained unchanged in all other groups (Group × Drug interaction). This effect may be due to selective upregulation of alpha2-adrenergic receptors after childhood trauma, which reduces capacity for attention focus on heartbeats. The sympathetic neural pathway including alpha2-adrenergic circuitries may be essential for mediating interoceptive signal transmission. Suppressed processing of physical sensations in stressful situations may represent an adaptive response in healthy individuals who experienced ACE.

This systematic review synthesizes the empirical literature examining pragmatic language in children diagnosed with attention-deficit/hyperactivity disorder (ADHD). Using a taxonomy of pragmatic language, we compared the pragmatic language profiles of children with ADHD to those of typically developing (TD) children and children with autism. Three databases were searched up to October 2019: PsychInfo; PubMed; and CSA Linguistics and Language Behavior Abstracts. We included 34 studies reporting on 2,845 children (ADHD = 1,407; TD = 1,058; autism = 380). Quality and risk of bias assessments included sample size and representativeness; measure reliability and validity; and missing data management. Children with ADHD were found to have higher rates of pragmatic difficulties than their TD peers. Specific difficulties were identified with inappropriate initiation, presupposition, social discourse, and narrative coherence. Children with ADHD appear to differ from those with autism in the degree of their pragmatic language impairments. General language skills contribute to, but do not explain, pragmatic difficulties in samples of children with ADHD. Though the extant evidence is limited, a preliminary profile of the pragmatic language impairments in children with ADHD is indicated. This supports a call for evidence-based interventions that include pragmatic language skills training.

Conventional longitudinal behavioral genetic models estimate the relative contribution of genetic and environmental factors to stability and change of traits and behaviors. Longitudinal models rarely explain the processes that generate observed differences between genetically and socially related individuals. We propose that exchanges between individuals and their environments (i.e., phenotype–environment effects) can explain the emergence of observed differences over time. Phenotype–environment models, however, would require violation of the independence assumption of standard behavioral genetic models; that is, uncorrelated genetic and environmental factors. We review how specification of phenotype–environment effects contributes to understanding observed changes in genetic variability over time and longitudinal correlations among nonshared environmental factors. We then provide an example using 30 days of positive and negative affect scores from an all-female sample of twins. Results demonstrate that the phenotype–environment effects explain how heritability estimates fluctuate as well as how nonshared environmental factors persist over time. We discuss possible mechanisms underlying change in gene–environment correlation over time, the advantages and challenges of including gene–environment correlation in longitudinal twin models, and recommendations for future research.

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.”

Research on the effects of adversity has led to mounting interest in examining the differential impact of adversity as a function of its timing and type. The current study examines whether the effects of different types (i.e., physical, sexual, and emotional abuse) and timing (i.e., early, middle childhood, adolescence, or adulthood) of adversity on maternal mental and physical health outcomes in pregnancy, are best accounted for by a cumulative model or independent effects model. Women from a prospective pregnancy cohort (N =3,362) reported retrospectively on their experiences of adversity (i.e., physical, sexual, and emotional abuse) in early childhood (0–5 years], middle childhood (6–12 years], adolescence (13–18 years], and adulthood (19+ years]. Measures of overall health, stress, anxiety, and depression were gathered in pregnancy. Results showed that a cumulative formative latent model was selected as more parsimonious than a direct effects model. Results also supported a model where the strength of the effect of adversity did not vary across abuse timing or type. Thus, cumulative adversity resulted in greater physical and mental health difficulties. In conclusion, cumulative adversity is a more parsimonious predictor of maternal physical and mental health outcomes than adversity at any one specific adversity timing or subtype.

Erikson's psychosocial developmental theory assumes that valence of one's identity (i.e., identity content valence) defined by positive and negative identity elements is important for understanding patterns of (mal)adaptation. However, previous empirical research on identity and (mal)adaptation has focused on how individuals deal with identity issues (e.g., exploration and commitment), while neglecting identity content valences. In contrast, this study assessed identity content valences in terms of positive and negative identity elements. Theoretically, identity content valences affect (mal)adaptation, whereas individuals’ (mal)adaptation influences their identities. Consequently, this study examined reciprocal relationships between identity content valences and adaptation (i.e., prosocial behaviors) and maladaptation (e.g., externalizing symptoms) in a sample of Japanese young adults, including socioculturally relevant indicators of maladaptation (i.e., hikikomori symptoms and suicidal ideation). This study includes 2,313 Japanese young adults who participated in a three-wave longitudinal study. The cross-lagged panel model and random intercept cross-lagged panel model revealed reciprocal relationships between identity content valences and (mal)adaptation at the between-person level. Negative identity elements positively predicted suicidal ideation. Meanwhile, prosocial behaviors positively predicted positive identity elements, whereas hikikomori symptoms and suicidal ideation positively predicted negative identity elements. These relationships were significant only for socioculturally relevant indicators, suggesting the importance of considering sociocultural contexts.

Self-regulation is considered a major predictor of crime and deviant behavior. However, longitudinal research investigating these associations, frequently looked only at the effect of self-regulation on deviant behavior, but not the other way around. The current study argued that deviance may contribute to later problems in self-regulation, and examined bidirectional associations, comparing a unidirectional and bidirectional model of associations between these variables. A Random Intercept Cross-Lagged Panel Model and eight data waves from 772 participants, aged 10–12 years to 30 years were used. Results showed that a bidirectional model fit the data better than a unidirectional model. The final model revealed an influence of deviance on self-regulation mainly in adolescence, whereas self-regulation influenced deviance only over two time points in adulthood. The results suggest that, in adolescence, problems in self-regulation may follow, rather than precede deviant behavior. Thus, decreasing deviant behavior or intervening in the aftermaths of deviant behavior in adolescence might have a positive effect on self-regulation in young adulthood, lowering the chance of adult deviant behavior. The current study shows that the long-presumed directionality of self-regulation to deviance can lead to bias, and more rigorous longitudinal research is needed in order to further inform theory and practice.

Irritability is a transdiagnostic feature of diverse forms of psychopathology and a rapidly growing literature implicates the construct in child maladaptation. However, most irritability measures currently used are drawn from parent-report questionnaires not designed to measure irritability per se; furthermore, parent report methods have several important limitations. We therefore examined the utility of observational ratings of children's irritability in predicting later psychopathology symptoms. Four-hundred and nine 3-year-old children (208 girls) completed observational tasks tapping temperamental emotionality and parents completed questionnaires assessing child irritability and anger. Parent-reported child psychopathology symptoms were assessed concurrently to the irritability assessment and when children were 5 and 8 years old. Children's irritability observed during tasks that did not typically elicit anger predicted their later depressive and hyperactivity symptoms, above and beyond parent-reported irritability and context-appropriate observed anger. Our findings support the use of observational indices of irritability and have implications for the development of observational paradigms designed to assess this construct in childhood.