Examining associations between genetic and neural risk for externalizing behaviors in adolescence and early adulthood.

BACKGROUND: Researchers have identified genetic and neural risk factors for externalizing behaviors. However, it has not yet been determined if genetic liability is conferred in part through associations with more proximal neurophysiological risk markers. METHODS: Participants from the Collaborative Study on the Genetics of Alcoholism, a large, family-based study of alcohol use disorders were genotyped and polygenic scores for externalizing (EXT PGS) were calculated. Associations with target P3 amplitude from a visual oddball task (P3) and broad endorsement of externalizing behaviors (indexed via self-report of alcohol and cannabis use, and antisocial behavior) were assessed in participants of European (EA; N = 2851) and African ancestry (AA; N = 1402). Analyses were also stratified by age (adolescents, age 12-17 and young adults, age 18-32). RESULTS: The EXT PGS was significantly associated with higher levels of externalizing behaviors among EA adolescents and young adults as well as AA young adults. P3 was inversely associated with externalizing behaviors among EA young adults. EXT PGS was not significantly associated with P3 amplitude and therefore, there was no evidence that P3 amplitude indirectly accounted for the association between EXT PGS and externalizing behaviors. CONCLUSIONS: Both the EXT PGS and P3 amplitude were significantly associated with externalizing behaviors among EA young adults. However, these associations with externalizing behaviors appear to be independent of each other, suggesting that they may index different facets of externalizing.

Changing adolescent activity patterns and the correlation of self-esteem and externalizing mental health symptoms across time: results from the USA from 1991 through 2020.

BACKGROUND: Common adolescent psychiatric symptoms cluster into two dominant domains: internalizing and externalizing. Both domains are linked to self-esteem, which serves as a protective factor against a wide range of internalizing and externalizing problems. This study examined trends in US adolescents' self-esteem and externalizing symptoms, and their correlation, by sex and patterns of time use. METHODS: Using Monitoring the Future data (N = 338 896 adolescents, grades:8/10/12, years:1991-2020), we generated six patterns of time use using latent profile analysis with 17 behavior items (e.g. sports participation, parties, paid work). Groups were differentiated by high/low engagement in sports and either paid work or high/low peer socialization. Within each group, we mapped annual, sex-stratified means of (and correlation between) self-esteem and externalizing factors. We also examined past-decade rates of change for factor means using linear regression and mapped proportions with top-quartile levels of poor self-esteem, externalizing symptoms, or both. RESULTS: We found consistent increases in poor self-esteem, decreases in externalizing symptoms, and a positive correlation between the two across nearly all activity groups. We also identified a relatively constant proportion of those with high levels of both in every group. Increases in poor self-esteem were most pronounced for female adolescents with low levels of socializing, among whom externalizing symptoms also increased. CONCLUSIONS: Rising trends in poor self-esteem are consistent across time use groups, as is the existence of a group facing poor self-esteem and externalizing symptoms. Effective interventions for adolescents' poor self-esteem/co-occurring symptoms are needed broadly, but especially among female adolescents with low peer socialization.

Prenatal cocaine exposure and self-reported behavioral adjustments from ages 12 to 21: environmental pathways.

BACKGROUND: In a birth-cohort study, we followed offspring with prenatal cocaine exposure (PCE) to investigate longitudinal associations of PCE with self-reported behavioral adjustment from early adolescence to emerging adulthood (EA). Environmental pathways (family functioning, non-kinship care, maltreatment) were specified as potential mediators of PCE. METHODS: Participants were 372 (190 PCE; 47% male), primarily Black, low socioeconomic status, enrolled at birth. Internalizing and externalizing behaviors were assessed using Youth Self-Report at ages 12 and 15 and Adult Self-Report at age 21. Extended random-intercept cross-lagged panel modeling was used to account for potential bidirectional relationships between internalizing and externalizing behaviors over time, examining potential mediators. RESULTS: Adjusting for covariates, significant indirect effects were found for each mediator at different ages. For family functioning, these were both internalizing (ß = 0.83, p = 0.04) and externalizing behaviors (ß = 1.58, p = 0.02) at age 12 and externalizing behaviors at age 15 (ß = 0.51, p = 0.03); for non-kinship care, externalizing behaviors at ages 12 (ß = 0.63, p = 0.02) and 15 (ß = 0.20, p = 0.03); and for maltreatment, both internalizing and externalizing behaviors at ages 15 (ß = 0.64, p = 0.02 for internalizing; ß = 0.50, p = 0.03 for externalizing) and 21 (ß = 1.39, p = 0.01 for internalizing; ß = 1.11, p = 0.01 for externalizing). Direct associations of PCE with internalizing and externalizing behaviors were not observed, nor cross-lagged relationships between internalizing and externalizing behaviors. CONCLUSIONS: Negative associations of PCE with behavioral adjustment persist into EA via environmental pathways, specifying intervention points to disrupt adverse pathways toward healthy development.

Genotype-environment interplay in associations between maternal drinking and offspring emotional and behavioral problems.

BACKGROUND: While maternal at-risk drinking is associated with children's emotional and behavioral problems, there is a paucity of research that properly accounts for genetic confounding and gene-environment interplay. Therefore, it remains uncertain what mechanisms underlie these associations. We assess the moderation of associations between maternal at-risk drinking and childhood emotional and behavioral problems by common genetic variants linked to environmental sensitivity (genotype-by-environment [G × E] interaction) while accounting for shared genetic risk between mothers and offspring (GE correlation). METHODS: We use data from 109 727 children born to 90 873 mothers enrolled in the Norwegian Mother, Father, and Child Cohort Study. Women self-reported alcohol consumption and reported emotional and behavioral problems when children were 1.5/3/5 years old. We included child polygenic scores (PGSs) for traits linked to environmental sensitivity as moderators. RESULTS: Associations between maternal drinking and child emotional (ß1 = 0.04 [95% confidence interval (CI) 0.03-0.05]) and behavioral (ß1 = 0.07 [0.06-0.08]) outcomes attenuated after controlling for measured confounders and were almost zero when we accounted for unmeasured confounding (emotional: ß1 = 0.01 [0.00-0.02]; behavioral: ß1 = 0.01 [0.00-0.02]). We observed no moderation of these adjusted exposure effects by any of the PGS. CONCLUSIONS: The lack of strong evidence for G × E interaction may indicate that the mechanism is not implicated in this kind of intergenerational association. It may also reflect insufficient power or the relatively benign nature of the exposure in this sample.

Alcohol milestones and internalizing, externalizing, and executive function: longitudinal and polygenic score associations.

BACKGROUND: Although the link between alcohol involvement and behavioral phenotypes (e.g. impulsivity, negative affect, executive function [EF]) is well-established, the directionality of these associations, specificity to stages of alcohol involvement, and extent of shared genetic liability remain unclear. We estimate longitudinal associations between transitions among alcohol milestones, behavioral phenotypes, and indices of genetic risk. METHODS: Data came from the Collaborative Study on the Genetics of Alcoholism (n = 3681; ages 11-36). Alcohol transitions (first: drink, intoxication, alcohol use disorder [AUD] symptom, AUD diagnosis), internalizing, and externalizing phenotypes came from the Semi-Structured Assessment for the Genetics of Alcoholism. EF was measured with the Tower of London and Visual Span Tasks. Polygenic scores (PGS) were computed for alcohol-related and behavioral phenotypes. Cox models estimated associations among PGS, behavior, and alcohol milestones. RESULTS: Externalizing phenotypes (e.g. conduct disorder symptoms) were associated with future initiation and drinking problems (hazard ratio (HR)⩾1.16). Internalizing (e.g. social anxiety) was associated with hazards for progression from first drink to severe AUD (HR⩾1.55). Initiation and AUD were associated with increased hazards for later depressive symptoms and suicidal ideation (HR⩾1.38), and initiation was associated with increased hazards for future conduct symptoms (HR = 1.60). EF was not associated with alcohol transitions. Drinks per week PGS was linked with increased hazards for alcohol transitions (HR⩾1.06). Problematic alcohol use PGS increased hazards for suicidal ideation (HR = 1.20). CONCLUSIONS: Behavioral markers of addiction vulnerability precede and follow alcohol transitions, highlighting dynamic, bidirectional relationships between behavior and emerging addiction.

Partitioning the Genomic Components of Behavioral Disinhibition and Substance Use (Disorder) Using Genomic Structural Equation Modeling.

Externalizing behaviors encompass manifestations of risk-taking, self-regulation, aggression, sensation-/reward-seeking, and impulsivity. Externalizing research often includes substance use (SUB), substance use disorder (SUD), and other (non-SUB/SUD) "behavioral disinhibition" (BD) traits. Genome-wide and twin research have pointed to overlapping genetic architecture within and across SUB, SUD, and BD. We created single-factor measurement models-each describing SUB, SUD, or BD traits-based on mutually exclusive sets of European ancestry genome-wide association study (GWAS) statistics exploring externalizing variables. We then assessed the partitioning of genetic covariance among the three facets using correlated factors models and Cholesky decomposition. Even when the residuals for indicators relating to the same substance were correlated across the SUB and SUD factors, the two factors yielded a large correlation (rg = 0.803). BD correlated strongly with the SUD (rg = 0.774) and SUB (rg = 0.778) factors. In our initial decompositions, 33% of total BD variance remained after partialing out SUD and SUB. The majority of covariance between BD and SUB and between BD and SUD was shared across all factors, and, within these models, only a small fraction of the total variation in BD operated via an independent pathway with SUD or SUB outside of the other factor. When only nicotine/tobacco, cannabis, and alcohol were included for the SUB/SUD factors, their correlation increased to rg = 0.861; in corresponding decompositions, BD-specific variance decreased to 27%. Further research can better elucidate the properties of BD-specific variation by exploring its genetic/molecular correlates.

Interactions Between Genetic, Prenatal Substance Use, Puberty, and Parenting are Less Important for Understanding Adolescents' Internalizing, Externalizing, and Substance Use than Developmental Cascades in Multifactorial Models.

This study tested interactions among puberty-related genetic risk, prenatal substance use, harsh discipline, and pubertal timing for the severity and directionality (i.e., differentiation) of externalizing and internalizing problems and adolescent substance use. This is a companion paper to Marceau et al. (2021) which examined the same influences in developmental cascade models. Data were from the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort (n = 4504 White boys, n = 4287 White girls assessed from the prenatal period through 18.5 years). We hypothesized generally that later predictors would strengthen the influence of puberty-related genetic risk, prenatal substance use exposure, and pubertal risk on psychopathology and substance use (two-way interactions), and that later predictors would strengthen the interactions of earlier influences on psychopathology and substance use (three-way interactions). Interactions were sparse. Although all fourteen interactions showed that later influences can exacerbate or trigger the effects of earlier ones, they often were not in the expected direction. The most robust moderator was parental discipline, and differing and synergistic effects of biological and socially-relevant aspects of puberty were found. In all, the influences examined here operate more robustly in developmental cascades than in interaction with each other for the development of psychopathology and transitions to substance use.

Alcohol Use Disorder Polygenic Risk Scores and Trajectories of Early Adolescent Externalizing Behaviors: Examining the Role of Parenting and Family Conflict in the Racially/Ethnically Diverse ABCD Sample.

This study examined the independent and interactive effects of alcohol use disorder genome-wide polygenic scores (AUD-PGS) and parenting and family conflict on early adolescent externalizing behaviors. Data were drawn from White (N = 6181, 46.9% female), Black/African American (N = 1784, 50.1% female), and Hispanic/Latinx (N = 2410, 48.0% female) youth from the adolescent brain cognitive development Study (ABCD). Parents reported on youth externalizing behaviors at baseline (T1, age 9/10), 1-year (T2, age 10/11) and 2-year (T3, age 11/12) assessments. Youth reported on parenting and family environment at T1 and provided saliva or blood samples for genotyping. Results from latent growth models indicated that in general externalizing behaviors decreased from T1 to T3. Across all groups, higher family conflict was associated with more externalizing behaviors at T1, and we did not find significant associations between parental monitoring and early adolescent externalizing behaviors. Parental acceptance was associated with lower externalizing behaviors among White and Hispanic youth, but not among Black youth. Results indicated no significant main effect of AUD-PGS nor interaction effect between AUD-PGS and family variables on early adolescent externalizing behaviors. Post hoc exploratory analysis uncovered an interaction between AUD-PGS and parental acceptance such that AUD-PGS was positively associated with externalizing rule-breaking behaviors among Hispanic youth, but only when parental acceptance was very low. Findings highlight the important role of family conflict and parental acceptance in externalizing behaviors among early adolescents, and emphasize the need to examine other developmental pathways underlying genetic risk for AUD across diverse populations.

Sexual orientation and mental health in a US cohort of children: a longitudinal mediation study.

BACKGROUND: Sexual minorities, including children, are at increased risk for adverse mental health outcomes compared to their heterosexual peers, but longitudinal studies are needed to determine the factors that explain the associations between sexual minority identification and adverse mental health outcomes during this developmental period. We examined longitudinal associations between sexual orientation and mental health over 2 years in a US cohort of children (aged 9-10 at baseline) and two explanatory factors (increased social problems such as getting teased and decreased perceived school safety). We hypothesized that beginning to identify as gay/bisexual and consistently identifying as gay/bisexual would be associated with increases in internalizing (e.g. depression, anxiety) and externalizing (e.g. aggression) problems compared to consistently identifying as heterosexual, and these associations would be partially explained by increased social problems and decreased perceived school safety. METHODS: We used data from Waves 1-3 of the Adolescent Brain Cognitive Development study. The analytic sample included 5,574 children (46.0% female; 55.1% non-Hispanic White). RESULTS: Beginning to identify as gay/bisexual was associated with increased internalizing/externalizing problems, and consistently identifying as gay/bisexual was associated with increased internalizing problems, compared to consistently identifying as heterosexual. For those who consistently identified as gay/bisexual, increased disparities in internalizing problems were partially explained by increased social problems and decreased perceived school safety, and increased disparities in externalizing problems were partially explained by increased social problems. CONCLUSIONS: These findings suggest the health disparities affecting sexual minority children include both internalizing and externalizing problems, and social problems and feeling unsafe at school may be contributing factors.

Mapping potential pathways from polygenic liability through brain structure to psychological problems across the transition to adolescence.

BACKGROUND: We used a polygenic score for externalizing behavior (extPGS) and structural MRI to examine potential pathways from genetic liability to conduct problems via the brain across the adolescent transition. METHODS: Three annual assessments of child conduct problems, attention-deficit/hyperactivity problems, and internalizing problems were conducted across across 9-13 years of age among 4,475 children of European ancestry in the Adolescent Brain Cognitive DevelopmentSM Study (ABCD Study®). RESULTS: The extPGS predicted conduct problems in each wave (R2 = 2.0%-2.9%). Bifactor models revealed that the extPRS predicted variance specific to conduct problems (R2 = 1.7%-2.1%), but also variance that conduct problems shared with other measured problems (R2 = .8%-1.4%). Longitudinally, extPGS predicted levels of specific conduct problems (R2 = 2.0%), but not their slope of change across age. The extPGS was associated with total gray matter volume (TGMV; R2 = .4%) and lower TGMV predicted both specific conduct problems (R2 = 1.7%-2.1%) and the variance common to all problems in each wave (R2 = 1.6%-3.1%). A modest proportion of the polygenic liability specific to conduct problems in each wave was statistically mediated by TGMV. CONCLUSIONS: Across the adolescent transition, the extPGS predicted both variance specific to conduct problems and variance shared by all measured problems. The extPGS also was associated with TGMV, which robustly predicted conduct problems. Statistical mediation analyses suggested the hypothesis that polygenic variation influences individual differences in brain development that are related to the likelihood of conduct problems during the adolescent transition, justifying new research to test this causal hypothesis.

Between- and within-child level associations between externalizing and internalizing behavior problems in a nationally representative sample of US elementary school children.

BACKGROUND: Both transactional and common etiological models have been proposed as explanations of why externalizing behavior problems (EBP) and internalizing behavior problems (IBP) co-occur in children. Yet little research has empirically evaluated these competing theoretical explanations. We examined whether EBP and IBP are transactionally related at the within-child level while also identifying antecedents commonly associated with between-child differences in underlying stability of both EBP and IBP across elementary school. METHODS: We analyzed a nationally representative and longitudinal sample of US schoolchildren (N = 7,326; 51% male) using random-intercept cross-lagged panel modeling (RI-CLPM). We used teacher ratings of EBP and IBP as annually assessed from the spring of kindergarten (Mage = 6.12 years) through the spring of 5th grade (Mage = 11.09 years). Early childhood antecedents included child internal (i.e. inhibitory control, cognitive flexibility, working memory, and language/literacy) and external factors (i.e. parental warmth, harsh parenting, parenting stress, and maternal depressive symptoms). RESULTS: We found little evidence for within-child, transactional relations between EBP and IBP. Both types of behavior problems instead were substantially associated at the between-child level. Inhibitory control was the strongest common antecedent that explained this longitudinal overlap. Cognitive flexibility, working memory, language/literacy skills, and maternal depression contributed specifically to the stability of IBP. Measures of parenting were specific to the stability of EBP. CONCLUSIONS: Common etiological factors rather than transactional relations better explain the co-occurrence of EBP and IBP during elementary school. Inhibitory control is a promising target of early intervention efforts for schoolchildren at risk of displaying both EBP and IBP.

Contamination bias in the estimation of child maltreatment causal effects on adolescent internalizing and externalizing behavior problems.

BACKGROUND: When unaddressed, contamination in child maltreatment research, in which some proportion of children recruited for a nonmaltreated comparison group are exposed to maltreatment, downwardly biases the significance and magnitude of effect size estimates. This study extends previous contamination research by investigating how a dual-measurement strategy of detecting and controlling contamination impacts causal effect size estimates of child behavior problems. METHODS: This study included 634 children from the LONGSCAN study with 63 cases of confirmed child maltreatment after age 8 and 571 cases without confirmed child maltreatment. Confirmed child maltreatment and internalizing and externalizing behaviors were recorded every 2 years between ages 4 and 16. Contamination in the nonmaltreated comparison group was identified and controlled by either a prospective self-report assessment at ages 12, 14, and 16 or by a one-time retrospective self-report assessment at age 18. Synthetic control methods were used to establish causal effects and quantify the impact of contamination when it was not controlled, when it was controlled for by prospective self-reports, and when it was controlled for by retrospective self-reports. RESULTS: Rates of contamination ranged from 62% to 67%. Without controlling for contamination, causal effect size estimates for internalizing behaviors were not statistically significant. Causal effects only became statistically significant after controlling contamination identified from either prospective or retrospective reports and effect sizes increased by between 17% and 54%. Controlling contamination had a smaller impact on effect size increases for externalizing behaviors but did produce a statistically significant overall effect, relative to the model ignoring contamination, when prospective methods were used. CONCLUSIONS: The presence of contamination in a nonmaltreated comparison group can underestimate the magnitude and statistical significance of causal effect size estimates, especially when investigating internalizing behavior problems. Addressing contamination can facilitate the replication of results across studies.

Family dysfunction, stressful life events, and mental health problems across development in the offspring of parents with an affective disorder.

BACKGROUND: Offspring of parents with affective disorders (OAD) are at risk of developing a wide range of mental disorders. Deficits in the rearing environment and high levels of stress are well-known risk factors for negative outcomes in OAD. Building on prior research, we aim to examine the longitudinal relationships between family dysfunction, stressful life events, and mental health in OAD and control offspring of parents with no affective disorder. In the present study, we hypothesized that high levels of family dysfunction would be associated with more internalizing and externalizing problems across time in OAD than in controls, and that family dysfunction would mediate the relationship between stressful life events in adolescence and poor mental health in adulthood, particularly in OAD. METHODS: As part of the TRacking Adolescents' Lives Survey (TRAILS), 2230 participants (51% female, Mage = 11.1 years, SD = 0.6, at baseline) and their parents completed measures across six time points, spanning 15 years. Mental health, family dysfunction, and stressful life events were assessed with the Youth and Adult Self-Report, Family Assessment Device, and an in-house measure, respectively. RESULTS: Multi-group structured equation modeling revealed that family dysfunction was linked to internalizing and externalizing problems in OAD, but not controls, across time. Risk status did not moderate family dysfunction's mediation of the relationship between stressful life events and negative outcomes in adulthood. CONCLUSIONS: OAD show high sensitivity to dysfunction in the rearing environment across childhood and adolescence, which supports the use of family based interventions to prevent the development of mental disorders in high-risk youth.

Parenting practices, mental health, and electronic cigarette use among U.S. young adolescents: A longitudinal panel analysis, 2013-2018.

PURPOSE: This study examined prospective association of parenting practices related to tobacco use with adolescent e-cigarette use and the moderating role of mental health among U.S. young adolescents. METHODS: We study used multi-wave longitudinal data (2013-2018) drawn from the Population Assessment of Tobacco and Health Study. A total of 5114 young adolescents (12-14 years) who were not lost to follow-ups across four waves (Wave 1-4) comprised the study sample. Weighted logistic regression models along with generalized linear mixed modeling assessed the within-subject associations of parenting practices related to tobacco use (tobacco availability at parent/guardian's home, past-year parent talk about tobacco use, and rules about non-combustible tobacco use at home) with adolescent current e-cigarette use. RESULTS: Prevalence of having home rules about non-combustible tobacco use increased (74.5%-80.2%) and that of parent talk about tobacco use decreased (52.0%-33.9%) over time while tobacco availability at home did not show a specific trend. Tobacco availability at home was associated with increased odds of adolescent e-cigarette use (adjusted odd ratio[OR] = 2.25, 95% confidence interval[CI] = 1.72-2.95), and having home rules about non-combustible tobacco use was linked to decreased likelihood of e-cigarette use (adjusted OR = 0.72, 95% CI = 0.55-0.92). The magnitude of negative association between having rules about non-combustible tobacco and adolescent e-cigarette use was stronger among adolescents with internalizing problems but weaker among those with externalizing problems. CONCLUSIONS: Our findings highlight the important role of home-based interventions in discouraging young adolescents from e-cigarette use. Parents/guardians should consider adolescents' mental health to provide more efficient home- and/or clinical-based e-cigarette use prevention.

Longitudinal links from attachment with mothers and fathers to adolescent substance use: Internalizing and externalizing pathways.

The present study examined whether internalizing and externalizing symptoms may mediate the association between adolescent-mother and adolescent-father attachment and substance use. The sample included 167 adolescents (47% girls) who were assessed at five time points with approximately 1 year between each assessment, beginning in middle adolescence (Mage = 14.07) and ending in the transition to young adulthood (Mage = 18.39). The adolescents reported their perceived attachment with both their mother and father during middle adolescence (Times 1 and 2), their internalizing and externalizing symptoms during late adolescence (Times 3 and 4), and their alcohol use during the transition to young adulthood (Time 5). The results showed that less secure adolescent-father attachment, but not adolescent-mother attachment, was predictive of heightened externalizing and internalizing symptoms. In turn, heightened externalizing symptoms were predictive of heightened alcohol use. Despite the nonsignificant direct association between adolescent-father attachment and alcohol use, less secure adolescent-father attachment was indirectly predictive of greater alcohol use, mediated through heightened externalizing symptoms. The findings highlight the importance of close and trusting father-adolescent relationships in the development of psychopathology and substance use behaviors. The developmental cascade from a less secure adolescent-father attachment to greater externalizing symptoms and heightened substance use, as well as implications for prevention and intervention of young adult substance use, are discussed. RESEARCH HIGHLIGHTS: The differential pathways from adolescent-mother and adolescent-father attachment to substance use during the transition to young adulthood are not well known. Longitudinal data were used to test whether internalizing and externalizing symptoms may mediate the association between adolescent-mother and adolescent-father attachment and substance use. Less secure adolescent-father attachment predicted heightened internalizing and externalizing symptoms, and less secure adolescent-father attachment predicted greater alcohol use, mediated through heightened externalizing symptoms. The findings suggest that addressing insecure attachment with fathers during adolescence may reduce unhealthy substance use during the transition to young adulthood.

Conversation disruptions in early childhood predict executive functioning development: A longitudinal study.

Conversational turn-taking is a complex communicative skill that requires both linguistic and executive functioning (EF) skills, including processing input while simultaneously forming and inhibiting responses until one's turn. Adult-child turn-taking predicts children's linguistic, cognitive, and socioemotional development. However, little is understood about how disruptions to temporal contingency in turn-taking, such as interruptions and overlapping speech, relate to cognitive outcomes, and how these relationships may vary across developmental contexts. In a longitudinal sample of 275 socioeconomically diverse mother-child dyads (children 50% male, 65% White), we conducted pre-registered examinations of whether the frequency of dyads' conversational disruption during free play when children were 3 years old related to children's executive functioning (EF; 9 months later), self-regulation skills (18 months later), and externalizing psychopathology in early adolescence (age 10-12 years). Contrary to hypotheses, more conversational disruptions significantly predicted higher inhibition skills, controlling for sex, age, income-to-needs (ITN), and language ability. Results were driven by maternal disruptions of the child's speech, and could not be explained by measures of overall talkativeness or interactiveness. Exploratory analyses revealed that ITN moderated these relationships, such that the positive effect of disruptions on inhibition was strongest for children from lower ITN backgrounds. We discuss how adult-driven "cooperative overlap" may serve as a form of engaged participation that supports cognition and behavior in certain cultural contexts.

Sensitivity to psychosocial influences at age 3 predicts mental health in middle childhood.

Children vary in how sensitive they are to experiences, with consequences for their developmental outcomes. In the current study, we investigated how behavioral sensitivity at age 3 years predicts mental health in middle childhood. Using a novel repeated measures design, we calculated child sensitivity to multiple psychological and social influences: parent praise, parent stress, child mood, and child sleep. We conceptualized sensitivity as the strength and direction of the relationship between psychosocial influences and child behavior, operationalized as toothbrushing time, at age 3 years. When children were 5-7 years old (n = 60), parents reported on children's internalizing and externalizing problems. Children who were more sensitive to their parents' praise at age 3 had fewer internalizing (r = -0.37, p = 0.016, pFDR = 0.042) and externalizing (r = -0.35, p = 0.021, pFDR = 0.042) problems in middle childhood. Higher average parent praise also marginally predicted fewer externalizing problems (r = -0.33, p = 0.006, pFDR = 0.057). Child sensitivity to mood predicted fewer internalizing (r = -0.32, p = 0.013, pFDR = 0.042) and externalizing (r = -0.38, p = 0.003, pFDR = 0.026) problems. By capturing variability in how children respond to daily fluctuations in their environment, we can contribute to the early prediction of mental health problems and improve access to early intervention services for children and families who need them most. RESEARCH HIGHLIGHTS: Children differ in how strongly their behavior depends on psychosocial factors including parent praise, child mood, child sleep, and parent stress. Children who are more sensitive to their parents' praise at age 3 have fewer internalizing and externalizing problems at age 5-7 years. Child sensitivity to mood also predicts fewer internalizing and externalizing problems.

Air pollution and age-dependent changes in emotional behavior across early adolescence in the U.S.

Recent studies have linked air pollution to increased risk for behavioral problems during development, albeit with inconsistent findings. Additional longitudinal studies are needed that consider how emotional behaviors may be affected when exposure coincides with the transition to adolescence - a vulnerable time for developing mental health difficulties. This study investigates if annual average PM2.5 and NO2 exposure at ages 9-10 years moderates age-related changes in internalizing and externalizing behaviors over a 2-year follow-up period in a large, nationwide U.S. sample of participants from the Adolescent Brain Cognitive Development (ABCD) Study®. Air pollution exposure was estimated based on the residential address of each participant using an ensemble-based modeling approach. Caregivers answered questions from the Child Behavior Checklist (CBCL) at the baseline, 1-year follow-up, and 2-year follow-up visits, for a total of 3 waves of data; from the CBCL we obtained scores on internalizing and externalizing problems plus 5 syndrome scales (anxious/depressed, withdrawn/depressed, rule-breaking behavior, aggressive behavior, and attention problems). Zero-inflated negative binomial models were used to examine both the main effect of age as well as the interaction of age with each pollutant on behavior while adjusting for various socioeconomic and demographic characteristics. Against our hypothesis, there was no evidence that greater air pollution exposure was related to more behavioral problems with age over time.

Sex-specific associations between co-exposure to multiple metals and externalizing symptoms in adolescence and young adulthood.

Externalizing disorders, such as attention-deficit/hyperactivity disorder (ADHD), account for the majority of the child/adolescent referrals to mental health services and increase risk for later-life psychopathology. Although the expression of externalizing disorders is more common among males, few studies have addressed how sex modifies associations between metal exposure and adolescent externalizing symptoms. This study aimed to examine sex-specific associations between co-exposure to multiple metals and externalizing symptoms in adolescence and young adulthood. Among 150 adolescents and young adults (55% female, ages: 15-25 years) enrolled in the Public Health Impact of Metals Exposure (PHIME) study in Brescia, Italy, we measured five metals (manganese (Mn), lead (Pb), copper (Cu), chromium (Cr), nickel (Ni)) in four biological matrices (blood, urine, hair, and saliva). Externalizing symptoms were assessed using the Achenbach System of Empirically Based Assessment (ASEBA) Youth Self-Report (YSR) or Adult Self Report (ASR). Using generalized weighted quantile sum (WQS) regression, we investigated the moderating effect of sex (i.e., assigned at birth) on associations between the joint effect of exposure to the metal mixture and externalizing symptoms, adjusting for age and socioeconomic status. We observed that metal mixture exposure was differentially associated with aggressive behavior in males compared to females (ß = -0.058, 95% CI [-0.126, -0.009]). In males, exposure was significantly associated with more externalizing problems, and aggressive and intrusive behaviors, driven by Pb, Cu and Cr. In females, exposure was not significantly associated with any externalizing symptoms. These findings suggest that the effect of metal exposure on externalizing symptoms differs in magnitude between the sexes, with males being more vulnerable to increased externalizing symptoms following metal exposure. Furthermore, our findings support the hypothesis that sex-specific vulnerabilities to mixed metal exposure during adolescence/young adulthood may play a role in sex disparities observed in mental health disorders, particularly those characterized by externalizing symptoms.

Gestational PBDE concentrations, persistent externalizing, and emerging internalizing behaviors in adolescents: The HOME study.

BACKGROUND: Polybrominated diphenyl ethers (PBDEs) are ubiquitous environmental chemicals used as flame retardants in commercial and consumer products. Gestational PBDE concentrations are associated with adverse behaviors in children; however, the persistence of these associations into adolescence remains understudied. OBJECTIVE: We estimated the association of gestational PBDE serum concentrations with early adolescent self- and caregiver-reported behaviors at age 12 years and determined the consistency with previously observed associations in childhood with caregiver-reported behaviors in a prospective pregnancy and birth cohort. METHODS: We measured maternal serum concentrations of five individual PBDE congeners and created a summary exposure variable (∑5BDE: 28, -47, -99, -100 and -153) during pregnancy. At age 12 years, we assessed behaviors for 237 adolescents using self- and caregiver-reports with the Behavioral Assessment System for Children-3 (BASC3). We used multivariable linear regression models to estimate covariate-adjusted associations of lipid standardized, log10-transformed gestational PBDE concentrations with BASC3 scores. We obtained estimates and 95% confidence intervals through a bootstrapping approach. We evaluated potential effect measure modification (EMM) of adolescent sex by examining sex-stratified regression models and estimating the EMM p-values. RESULTS: Gestational PBDE concentrations were positively associated with adolescent-reported BASC3 composite indices for inattention & hyperactivity (BDE-28, -47, -99, -100, ∑5BDE), internalizing problems (BDE-28, -47, -99), functional impairment (BDE-28, ∑5BDE), and emotional symptoms (BDE-28). Gestational PBDE concentrations were positively associated with caregiver-reported BASC3 composite indices for externalizing problems (BDE-28, -47, -99, -100, -153, ∑5BDE) and behavioral symptoms (BDE-99). For caregiver reported behaviors, we observed stronger associations with gestational BDE concentrations among males, especially for executive functioning (BDE-28, -47, -99, -100, ∑5BDE). DISCUSSION: Gestational PBDE serum concentrations were associated with self-reported internalizing and externalizing behavior problems in early adolescence. Caregiver-reported externalizing behaviors recognized during childhood remain associated with gestational PBDE concentrations and persist into early adolescence. Internalizing behaviors were less recognized by caregivers.