Individual differences in personality have long been linked to the use and misuse of alcohol, tobacco, cannabis, and other drugs. Broadly, personality characteristics of high neuroticism and behavioral undercontrol/impulsivity appear to robustly relate to several substance use disorders (SUDs), although other traits have also been linked to SUDs. Much of the genetic basis of SUDs appears to be mediated by personality traits, which may relate to SUDs through a variety of non-mutually exclusive mechanisms that may work additively and synergistically, are indexed by various motivations associated with reward seeking and regulating negative emotion, and also relate to self-control and environment selection. Considerable change occurs in personality over the life course, and recent data show that the course of substance use and SUDs is associated with personality change. Although much progress has been made, several lines of future research could be pursued to further our understanding of the personality–SUD relation.
