Self-Determination and Substance Use: Is Effortful Control a Mediator?

Background Alcohol and other drug use among college students are highly common in the United States. This study examined the relationships between 2 motivational orientations (i.e., autonomy and controlled orientations) and substance use and related problems among college students. It also examined whether effortful control mediated the relationship between these motivational orientations and substance use. Methods Study participants were 644 undergraduate students (67.2% female; 87.2% Caucasian) who completed a series of online questionnaires as a part of a larger longitudinal study on sleep and substance use. The mean age of participants was 23.58 (SD=6.861). Results Students with a higher autonomy orientation were more likely than their counterparts to report that they did not drink in the last 6months. In contrast, students with a higher controlled orientation were less likely to report that they did not drink. Among those who drank in the last 6months, effortful control significantly mediated the effects of autonomy orientation and controlled orientation on frequency of alcohol use within that time frame. Autonomy orientation positively predicted effortful control, which was associated with a decrease in the expected frequency of drinking. In contrast, controlled orientation negatively predicted effortful control, which was associated with an increase in the expected frequency of drinking. Controlled orientation also significantly predicted the presence of alcohol-related problems and illicit drug use. Conclusions Intervention and prevention programs on college drinking could incorporate education about strategies for self-control, including strategies for withstanding peer pressure and diverting one's attention to activities unrelated to substance use. Focusing on strategies of self-control may be a useful starting point for a more in-depth discussion about the motivations, values, and psychological needs satisfaction that are associated with drinking and other drug use.