Impulsivity is clearly associated with adolescent substance use. However, contemporary models of impulsivity argue against a unitary construct and propose at least two potential facets of impulsivity: reward drive and disinhibition. This study investigated the mediating role of prosocial risk-taking in the association between these two facets of impulsivity, family environment, and substance use in Grade 8 students, age 12–14 years (N = 969). For girls, traits related to disinhibition referred to as rash impulsivity were directly associated with greater substance use and, unexpectedly, reward drive was indirectly associated with greater substance use through participation in physical-risk activities, which itself predicted greater use. For boys, participation in physical-risk activities was the only direct predictor of substance use and, as in girls, reward drive conveyed indirect risk through this pathway. Family environment, reward drive, and rash impulsivity were associated with participation in performance-risk activities, and prosocial behavior more generally, but neither of these hypothesized mediators was related to substance use.
Journal of Adolescence / Vol. 36, No. 5, pp.871-881