Matching Items (2)
Description
This study examined whether early adversity at 30-months moderated the heritability of common and individual components of EF at 8 years. It was hypothesized that early adversity would not moderate the common EF factor, but instead moderate individual EF components. The sample included 208 twin pairs from the Arizona Twin Project. Early Adversity, assessed at 30 months of age, included Parenting Daily Hassles, low perceived MOS social support, punitive punishment (Parental Responses to Child Misbehavior), home chaos (Confusion, Hubbub, and Order Scale), CES-D maternal depression, and low maternal emotional availability. EF at 8 years included the Eriksen Flanker Task, Continuous Performance Task, Digit Span Forward and Backward, and parent-reported Attentional Focusing and Inhibitory Control (Temperament in Middle Childhood Questionnaire). For both early adversity and EF, the first principal components were extracted as composites. A confirmatory factor analysis was also conducted to index common EF. Genetic analyses were tested on the common EF composites as well as each individual task using umx. Univariate models revealed genetic influences on all individual measures and common EF, with broad sense heritability from .22 (Digit Span Backwards) to .61 (parent-reported inhibitory control). Shared environmental influences were found for the Flanker Task (.13) and parent-reported inhibitory control (.24), and E was moderate to high (.40-.73) for all measures except parent-report inhibitory control (.15) and attentional focusing (.31). Moderation of heritability was not observed in for Digit Span Forward, Digit Span Backward, and Attentional Focusing. However, the nonshared environment was moderated for Common EF, and the Flanker Task, and additive genes and the nonshared environment were moderated for the Continuous Performance Task and Inhibitory Control. Generally, total variance decreased as early adversity increased, suggesting that homes with low levels of adversity may allow children to interact with more proximal processes that can promote EF development.
ContributorsRea-Sandin, Gianna (Author) / Lemery-Chalfant, Kathryn (Thesis advisor) / Elam, Kit (Committee member) / Bradley, Robert (Committee member) / Arizona State University (Publisher)
Created2018
Description
This study examined whether social support available to parents moderated the heritability of parent-reported social approach at 12 months (N = 286 twin pairs, 52.00% female) and social competence at 30 months (N = 259 twin pairs, 53.30% female). Genetic and environmental covariance across age is also reported. Social support consistently moderated genetic influences on children’s social approach and competence, such that heritability was highest when parents reported low social support. Shared environment was not moderated by social support and explained continuity across age. Findings provide further evidence that genetic and environmental influences on development vary across context. When parents are supported, environmental influences on children’s social competence are larger, perhaps because support helps parents provide a broadly promotive environment.
ContributorsClifford, Sierra (Author) / Lemery-Chalfant, Kathryn (Thesis advisor) / Doane, Leah (Committee member) / Shiota, Michelle (Committee member) / Grimm, Kevin (Committee member) / Arizona State University (Publisher)
Created2017