Impulsivity, negative expectancies, and marijuana use: a test of the acquired preparedness model.

According to the 'acquired preparedness model,' expectancies mediate the relationship between an impulsive personality style and alcohol use. The current study evaluated whether the model can also be applied to marijuana use. Estimated probabilities and subjective evaluations of personally expected marijuana effects, along with impulsivity and frequency of marijuana use, were assessed in 337 college undergraduates. Tests of mediation examining positive and negative marijuana expectancies showed negative expectancies to be a significant mediator for both males and females. That is, participants who were higher on impulsivity had fewer negative expectancies and in turn used more marijuana. This study provides evidence that the acquired preparedness model may help to explain marijuana use.