Acquired preparedness model and impulsivity moderated expectancies: Examining predictors of marijuana use

The acquired preparedness model suggests that links between personality and substance use are mediated by expectancies. In contrast, expectancy-moderated links between personality and substance use also have support in previous research. This study sought to extend the acquired preparedness model to a diverse sample of frequent marijuana users. Tension-reduction expectancies, impulsivity, and ounces of marijuana used per month were assessed in 5996 participants recruited from a marijuana policy listserv. Tension-reduction expectancies partially mediated the relation between impulsivity and marijuana use. Additionally, expectancies and impulsivity interacted to predict marijuana use, with impulsivity showing a stronger link to use when expectancies increased. These findings support the acquired preparedness model of substance use as well as previous work on expectancy-moderated links between personality and substance use. Impulsive individuals are particularly likely to use substances when they have positive expectancies about them. Challenging these marijuana expectancies might prove useful in preventing problematic use.