CONTEXTUAL INFLUENCES OF PRENATAL AND POSTNATAL ENVIRONMENTS ON EXECUTIVE FUNCTION RISK FOR ADOLESCENT SUBSTANCE USE

Due to the great transitions and turmoil uniquely attributed to the period of adolescence, youth experience a greater risk for substance use and the multitude of concerns that coincide with the early onset of substance use. Many biological and environmental factors have been investigated as predictors of adolescent substance use. Executive function and disruptive behaviors are two important individual characteristics linked to adolescent substance use. Both smoking during pregnancy and sibling relationships are separate contexts that can mitigate or exacerbate the associations of executive function and adolescent substance use. The present study focuses on development of substance use through executive function deficits and disruptive behavior, while considering smoking during pregnancy and sibling relationships as unique moderators of these pathways. This work addresses a novel, interrelated set of questions with a series of three studies. The central hypothesis driving this program of research is that smoking during pregnancy and sibling relationships are under-studied contexts that can mitigate or exacerbate the associations of executive function, disruptive behavior, and adolescent substance use. This dissertation examines whether: (1) executive function mediates the smoking during pregnancy-disruptive behavior association and smoking during pregnancy exacerbates the executive function-disruptive behavior association, (2) smoking during pregnancy exacerbates the association between executive function and disruptive behavior during adolescence using a sibling comparison design, and (3) sibling relationship quality moderates developmental trajectories of executive function on the transition from disruptive problems to adolescent substance use using a high-risk, longitudinal sample. Findings challenge the link between exposure to smoking during pregnancy and both executive function and disruptive behavior. Further, these findings reinforce the need to utilize genetically-informed designs when examining potential effects of smoking during pregnancy. Additionally, this dissertation found support for the link between executive function and disruptive behavior, but not executive function and substance use.