Alison Pike

Nonshared Environmental Influences on Individual Differences in Early Behavioral Development: A Monozygotic Twin Differences Study

The monozygotic (MZ) twin differences method was used to investigate nonshared environmental (NSE) influences independent of genetics. Four-year-old MZ twin pairs (N = 2,353) were assessed by their parents on 2 parenting measures (harsh parental discipline and negative parental feelings) and 4 behavioral measures (anxiety, prosocial behavior, hyperactivity, and conduct problems). Within-pair differences in parenting correlated significantly with MZ differences in behavior, with an average effect size of 3%. For the extreme 10% of the parenting-discordant and behavior-discordant distributions, the average NSE effect size was substantially greater (11%), suggesting a stronger NSE relationship for more discordant twins. NSE relationships were also stronger in higher risk environments, that is, families with lower socioeconomic status, greater family chaos, or greater maternal depression.

Genetic and environmental influences in adolescent peer socialization: evidence from two genetically sensitive designs

Harris argues that peer relationships are the chief determinants of personality development. Harriss thesis makes the behavioral genetic investigation of peer groups particularly timely. The present study examined genetic and environmental contribution to self-reported peer-group characteristics in two samples of adolescent siblings: 180 adoptive and nonadoptive sibling pairs from the Colorado Adoption Project, and 386 sibling pairs from the Nonshared Environment and Adolescent Development Study. Substantial genetic influence emerged for college orientation, with the remaining variance accounted for by nonshared environment. For delinquency, however, the majority of the variance was explained by nonshared environment. Although genetic influence was implicated for peer popularity in twin analyses, genetic factors were not important in explaining individual differences in nontwin siblings. These results suggest that although some dimensions of peers are somewhat mediated by genetic factors, nonshared environmental influence is substantial.

Environmental risk and young children’s cognitive and behavioral development

Using a longitudinal, large-scale sample of British twins, we addressed the prediction of both cognitive abilities and behavioral adjustment from eight domains of environmental risk: minority status, socio-economic status, maternal medical factors, twin medical factors, maternal depression, chaos within the home environment, and parental feelings towards their children and discipline. Participants included 5765 families with twins (49.1% male) born in 1994 and 1995. Aspects of environmental risk were assessed from birth until the children’s third birthdays; outcome measures were assessed at their fourth birthdays. Overall prediction of outcome (via multiple regression analysis) was moderate (R = .23 -.48). SES and chaos were the strongest predictors for the cognitive outcomes whereas for total behavior problems the more proximal parenting factors were also dominant. Future analyses will investigate these environmental risk indicators in the context of the genetically sensitive twin design.

Nonshared environmental processes in social‐emotional development: an observational study of identical twin differences in the preschool period

Differences in mothers’ parenting behaviors toward their identical twin preschoolers were examined to identify nonshared environmental processes in social-emotional development. The study included 62 pairs of 3½-year-old same-sex identical twins. Indicators of each child’s social-emotional development (temperament, prosocial behavior, behavior problems and noncompliance) and parenting environment (warmth and negativity, positive and negative control, responsiveness) were assessed using observers’, interviewers’, and parents’ ratings. Mothers treated their identical twins differently, and this differential treatment covaried in expected ways with identical twin differences in social-emotional adjustment. The twin who received more supportive and less punitive forms of parenting was also higher in positive mood and prosocial behaviors and lower in negative mood and behavior problems when compared to her or his twin.

Mother- and father-child mutuality in anglo and Indian British families: A link with lower externalizing problems

We observed Mother— and Father—Child dyadic mutuality (responsiveness, interaction reciprocity, and cooperation), and its association with child behavior problems, in a socioeconomically and ethnically diverse sample of 125 male (51%) and female 7-to-9-year-old children. Dyadic mutuality and positivity were coded from in-home videotaped structured tasks, and parents completed ratings of child externalizing problems. Mothers showed more mutuality than fathers. The same child showed moderately similar mutuality with both of her or his parents (r = .47). Mutuality was higher among Anglo parents compared to Indian parents, an effect that was due in part to acculturation (i.e., years since immigration, native language use, traditional native culture attitudes). Greater mutuality, when coupled with dyadic positive affect, was associated with fewer externalizing problems (R2 = .24). This pattern held across gender, ethnic, and socioeconomic groups.

Maternal scaffolding behavior: Links with parenting style and maternal education

The purpose of this study was to specify the relationship between positive and harsh parenting and maternal scaffolding behavior. A 2nd aim was to disentangle the effects of maternal education and parenting quality, and a 3rd aim was to test whether parenting quality mediated the association between maternal education and scaffolding practices. We examined associations between positive and harsh parenting practices and contingent and noncontingent tutoring strategies. Ninety-six mother-child dyads (49 boys, 47 girls) from working- and middle-class English families participated. Mothers reported on parenting quality at Time 1 when children were 5 years old and again approximately 5 years later at Time 2. Mother-child pairs were observed working together on a block design task at Time 2, and interactions were coded for contingent (contingent shifting) and noncontingent (fixed failure feedback) dimensions of maternal scaffolding behavior. Positive and harsh parenting accounted for variance in contingent behavior over and above maternal education, whereas only harsh parenting accounted for unique variance in noncontingent scaffolding practices. Our findings provide new evidence for a more differentiated model of the relation between general parenting quality and specific scaffolding behaviors.

The validity of a parent-based assessment of cognitive abilities in three-year olds

The purpose of the present study was to validate a parent-based assessment of cognitive abilities of three-year-old children against a standard tester-administered measure. The cognitive abilities of 85 children (50 boys and 35 girls, members of 43 twin pairs) were assessed using a measure of non-verbal abilities called the Parent Report of Childrens Abilities for three-year-olds (PARCA3), a vocabulary checklist, and the McCarthy Scales of Childrens Abilities (McCarthy, 1972). Correlations indicated that both components of the PARCA3 (parent-report and parent-administered) were significantly associated with the McCarthy scales, as was the vocabulary measure. Most importantly, the PARCA3 and vocabulary measure in combination significantly and substantially predict the McCarthy General Cognitive Index (Total R =0.63). We conclude that the PARCA3, with the vocabulary measure, provides a valid, inexpensive, reliable measure of cognitive ability for very young children.

Adolescent Perceptions as Mediators of Parenting: Genetic and Environmental Contributions.

Explaining how genetic factors contribute to associations between parenting and adolescent adjustment is an important next step in developmental research. This study examined the mediating effect of adolescent perceptions on these associations and the genetic and environmental influences underpinning the mediated relationship. Parent, adolescent, and observer ratings of parenting and adolescent adjustment were used in a genetically informative sample of 720 same-sex sibling pairs from 10 to 18 years old. Adolescent perceptions of parenting did significantly mediate a composite measure of parental conflict-negativity and adolescent antisocial behavior and depressive symptoms. The most substantial genetic contributions to the association between parenting and adolescent maladjustment were those mediated by adolescent perceptions. Once genetic and environmental contributions to adolescent perceptions of parenting were removed, shared environmental factors became more important for the remaining direct association.

Adolescents' relationships to siblings and mothers: A multivariate genetic analysis.

Research has consistently demonstrated that childrens behavior toward their siblings tends to resemble interactions occurring in the parent-child relationship. This study examined the relative contributions of genetic and environmental influences to the covariation between sibling relationships and mother-adolescent relationships. Reported and observed family interactions were assessed for 719 same-sex sibling pairs of varying degrees of genetic relatedness. The covariance between mother-adolescent and sibling interactions was decomposed into genetic, shared, and nonshared environmental components. The overlapping effects of shared environment on the two relationship subsystems explained most of the covariance. Smaller but significant genetic and nonshared environmental effects were also found. The consistency of these findings with family processes, such as modeling, is discussed.

Internalising and externalising problems in middle childhood: A study of Indian (ethnic minority) and English (ethnic majority) children living in Britain

The psychological adjustment of ethnic minority children has received little research attention, particularly in Britain. The present study set out to investigate the adjustment of Indian children living in Britain as well as the adjustment of their English peers. The sample consisted of 125 children (66 Indian and 59 English) between the ages of 7 and 9 years (M = 8.51, SD = 0.62) and their parents and teachers. Mothers, fathers, and teachers reported about the children’s problem behaviour, and parents also reported on their acculturation strategy and use of their Indian language. Analyses revealed that overall Indian children seem to be well adjusted in Britain. Nevertheless, according to parental reports, they exhibited more internalising problems than did their English peers. No significant differences, however, were found for externalising or total problem behaviour. Furthermore, within the Indian group, it was found that children whose mothers and fathers were more traditional in their acculturation style displayed lower levels of externalising, internalising and total problem behaviour, according to their teachers. In addition, children whose mothers and fathers utilised their Indian language to a greater extent displayed lower levels of externalising and total problem behaviour (teachers’ reports). These findings highlight the importance of examining the adjustment of ethnic minority children in multiple contexts.