Most studies have considered the effects of particular characteristics on academic achievement individually, which means that little is known about how they function together. Using the ...population-based Minnesota Twin Family Study, the authors investigated the effects of child academic engagement (interest, involvement, effort), IQ, depression, externalizing behavior, and family environmental risk on academic achievement (reported school grades) from ages 11 through 17. Hierarchical linear growth curve modeling showed main effects on initial reported Grades for all variables, and IQ mitigated the deleterious effects of family risk and externalizing. Only engagement affected change in Grades through adolescence. Influences on initial Grades were strongly genetically influenced, associated primarily with IQ, engagement, and externalizing behavior. Shared environmental influences on initial Grades linked engagement, IQ, and family risk. Genetic influences on change in Grades were substantial, but they were not associated with the academic, family risk, and mental health covarying factors. These results indicate that age 11 achievement and change in achievement through adolescence show systematic patterns and document the existence of individual differences in the commonly shared developmental experience of adapting to the school environment.
The ABCD twin study will elucidate the genetic and environmental contributions to a wide range of mental and physical health outcomes in children, including substance use, brain and behavioral ...development, and their interrelationship. Comparisons within and between monozygotic and dizygotic twin pairs, further powered by multiple assessments, provide information about genetic and environmental contributions to developmental associations, and enable stronger tests of causal hypotheses, than do comparisons involving unrelated children. Thus a sub-study of 800 pairs of same-sex twins was embedded within the overall Adolescent Brain and Cognitive Development (ABCD) design. The ABCD Twin Hub comprises four leading centers for twin research in Minnesota, Colorado, Virginia, and Missouri. Each site is enrolling 200 twin pairs, as well as singletons. The twins are recruited from registries of all twin births in each State during 2006–2008. Singletons at each site are recruited following the same school-based procedures as the rest of the ABCD study. This paper describes the background and rationale for the ABCD twin study, the ascertainment of twin pairs and implementation strategy at each site, and the details of the proposed analytic strategies to quantify genetic and environmental influences and test hypotheses critical to the aims of the ABCD study.
Theoretical and empirical work suggests that problematic substance use (PSU) is associated with individual differences in prefrontal cortex activity. While research has strongly linked parietal P3 ...amplitude reduction (P3AR) to genetic risk for problematic substance use, few studies have tested whether prefrontal EEG measures are sensitive to this genetic liability. In addition to P3, oddball target detection tasks elicit medial frontal theta power, reflecting attentional allocation, and parietal delta, indexing decision making or stimulus‐response link updating. Midfrontal theta and parietal delta may index neurocognitive processes relevant to PSU beyond P3AR. The present investigation examined the etiological relationship between PSU and P3, frontal theta, and parietal delta in a large twin sample (N = 754). EEG was recorded during a visual oddball task. Greater PSU was associated with reduced target P3 amplitude and midfrontal theta/parietal delta power, and increased mean reaction time and reaction time variability (RTV; indexing attentional fluctuations). P3, theta, and RTV, but not delta or mean RT, explained unique variance in PSU (R2 = 0.04). Twin biometric modeling indicated a genetic relationship between PSU and P3, theta, and RTV. Theta accounted for distinct genetic variance in PSU beyond P3 and RTV. Together, 23% of the total additive genetic variance in PSU was explained by the three endophenotypes. Results replicate P3AR as an endophenotype and provide support for additional behavioral (RTV) and neurophysiological (midfrontal theta) endophenotypes of PSU. Reduced theta and greater RTV may reflect variations in a prefrontal attentional network that confers genetic risk for substance use problems.
Most putative psychophysiological endophenotypes demonstrate familiality, but few have demonstrated that they share genetic variance with clinical phenotypes. In a large (N = 754) sample of late adolescent twins, we show that parietal P3, medial frontal theta power, and reaction time variability (RTV) elicited during a visual oddball task share genetic variance with problematic substance use (PSU). Together, the three measures explained 23% of the additive genetic variance in PSU. This study offers new evidence that genetically driven variations in psychophysiological and behavioral correlates of attention (theta; RTV) and decision making (P3) reflect distinct candidate endophenotypes for substance use risk.
Parental characteristics and practices predict borderline personality disorder (BPD) symptoms in children. However, it is difficult to disentangle whether these effects are genetically or ...environmentally mediated. The present study examines the contributions of genetic and environmental influences by comparing the effects of familial risk factors (i.e. parental psychopathology and borderline traits, maladaptive parenting, marital discord) on child BPD traits in genetically related (biological) and non-related (adoptive) families.
Data are from 409 adoptive and 208 biological families who participated in the Siblings Interaction and Behavior Study (SIBS) and 580 twin families the Minnesota Twin Family Study (MTFS). Parent characteristics and practices included parental psychopathology (measured via structured clinical interviews), parental BPD traits, parenting behaviors, and marital discord. A series of multi-level regression models were estimated to examine the relationship of familial risk factors to child BPD traits and to test whether children's adoptive status moderated the association.
Symptom counts of parents' conduct disorder, adult antisocial behavior, nicotine, alcohol, and illicit drug dependence, and paternal BPD traits substantially predicted child BPD traits only in biological offspring, implying genetic transmission. Maternal BPD traits and both maternal and paternal conflict, lack of regard, and lack of involvement predicted offspring BPD traits regardless of the adoptive status, implying environmental transmission.
Parental externalizing psychopathology and father's BPD traits contribute genetic risk for offspring BPD traits, but mothers' BPD traits and parents' poor parenting constitute environmental risks for the development of these offspring traits.
Prior research has demonstrated both socialization and selection effects for the relationship between antisocial peer affiliation and externalizing problems in adolescence. Less research has ...evaluated such effects postadolescence. In this study, a cross-lagged panel analysis was used to evaluate the extent of socialization (i.e., the effect of antisocial peer affiliation on subsequent externalizing disorders) and selection (i.e., the effect of externalizing disorders on subsequent antisocial peer affiliation) in the prospective relationships between antisocial peer affiliation and externalizing disorders from adolescence through young adulthood. Data from a community sample of 2,769 individuals (52% female) with assessments at ages 17, 20, 24, and 29 were used. Analyses with a latent externalizing measure (estimated using clinical symptom counts of nicotine dependence, alcohol use disorder, illicit drug use disorder, and adult antisocial behavior) and self-reported antisocial peer affiliation revealed significantly stronger socialization effects from age 17 to 20, followed by significantly stronger selection effects from age 20 to 24 and 24 to 29. To better understand the impact of college experience, moderation by college status was evaluated at each developmental transition. Results were generally consistent for those who were in or were not in college. Results suggest selection effects are more important in later developmental periods than earlier periods, particularly in relation to an overall liability toward externalizing disorders, likely due to more freedom in peer selection postadolescence.
We investigated intergenerational educational and occupational mobility in a sample of 2,594 adult offspring and 2,530 of their parents. Participants completed assessments of general cognitive ...ability and five noncognitive factors related to social achievement; 88% were also genotyped, allowing computation of educational-attainment polygenic scores. Most offspring were socially mobile. Offspring who scored at least 1 standard deviation higher than their parents on both cognitive and noncognitive measures rarely moved down and frequently moved up. Polygenic scores were also associated with social mobility. Inheritance of a favorable subset of parent alleles was associated with moving up, and inheritance of an unfavorable subset was associated with moving down. Parents’ education did not moderate the association of offspring’s skill with mobility, suggesting that low-skilled offspring from advantaged homes were not protected from downward mobility. These data suggest that cognitive and noncognitive skills as well as genetic factors contribute to the reordering of social standing that takes place across generations.
Though theory suggests that individual differences in neuroticism (a tendency to experience negative emotions) would be associated with altered functioning of the amygdala (which has been linked with ...emotionality and emotion dysregulation in childhood, adolescence, and adulthood), results of functional neuroimaging studies have been contradictory and inconclusive. We aimed to clarify the relationship between neuroticism and three hypothesized neural markers derived from functional magnetic resonance imaging during negative emotion face processing: amygdala activation, amygdala habituation, and amygdala-prefrontal connectivity, each of which plays an important role in the experience and regulation of emotions. We used general linear models to examine the relationship between trait neuroticism and the hypothesized neural markers in a large sample of over 500 young adults. Although neuroticism was not significantly associated with magnitude of amygdala activation or amygdala habituation, it was associated with amygdala-ventromedial prefrontal cortex connectivity, which has been implicated in emotion regulation. Results suggest that trait neuroticism may represent a failure in top-down control and regulation of emotional reactions, rather than overactive emotion generation processes, per se. These findings suggest that neuroticism, which has been associated with increased rates of transdiagnostic psychopathology, may represent a failure in the inhibitory neurocircuitry associated with emotion regulation.
A self-report measure of conflict and aspects of warmth in the parent-child relationship was completed by 1,330 11-year-old twins, 1,176 of whom completed the inventory again 3 years later. On ...average, adolescents' perceptions of the quality of the parent-child relationship declined consistently and moderately between age 11 and age 14. Conflict with parents increased, whereas all aspects of warmth decreased; changes were significantly greater for girls than boys. Variances increased with age, primarily because of increases in the magnitude of genetic effects. Heritability estimates ranged from .09 to .31 at intake and .35 to .45 at follow-up and tended to be higher for boys than girls. Changes in the parent-child relationship are interpreted as reflecting genotype-environment correlation processes whereby adolescents increasingly influence their relationships with their parents.
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