Cognitive processes in adolescent drug use: the role of positivity bias and implications for prevention policy.

Recent investigations of the role of expectations about the effects of alcohol in drinking behavior suggest that there is a functional relationship between expectancies and alcohol use. Specifically, greater positive expectancies are related to heavier drinking patterns. In contrast, expectations about the negative consequences of alcohol use seem to be unrelated to drinking behavior. These differential roles of positive and negative expectancies as mediators of alcohol use reflect the robust phenomenon of positivity bias in human information processing. The theoretical and clinical implications of this phenomenon with respect to adolescent drug use are discussed.