Executive dysfunction as a risk marker for substance abuse: the role of impulsive personality traits

The relationships between family history of substance use, executive functions, impaired decision making, and current substance dependence are the focus of this study. Thirty-eight substance-dependent inpatients were compared with 30 community controls on performance on the Wisconsin Card Sorting Test, Trail-Making Test-B, the Stroop Color Word Test, the Wais-II Digit Span, and the Iowa Gambling Task. Recent alcohol use, depressive symptoms, and impulsivity were also assessed. As hypothesized, individuals with substance dependence exhibited poorer executive functioning. Family history status was modestly related to impaired performance on tests designed to measure the integrity of the dorsolateral prefrontal cortex. In particular, substance-dependent, family history positive individuals performed less well on the Wisconsin Card Sorting Test than substance-dependent individuals without a family history. Digit Span performances were worse among family history positive controls when compared with family history negative controls. Impulsive personality traits--specifically, difficulty thinking before acting (Urgency)--were related, as hypothesized, to executive functioning. Results indicate that family history status confers an increased risk of impairment beyond that conferred by recent substance abuse, and that impulsive personality traits are related to performance on tests of executive functions. Implications for criminality are discussed.