Valuation of peers’ safe choices is associated with substance-naïveté in adolescents

Significance During adolescence, substance use and other health-risk behaviors emerge, particularly among those who associate with peers engaging in such behaviors and less so for adolescents with less deviant peers. Here, we provide behavioral and neural evidence for a beneficial role of safer peers, rather than a detrimental influence of risky peers, in guiding adolescents’ choices and substance use. The extent to which adolescents value peers’ safe choices predicted substance-naïveté even after controlling for other factors associated with substance use, while valuation of peers’ risky choices was unrelated to substance use. Whereas previous studies have largely examined associations between negative peers and increased health-risk behaviors, our data support a significant role of positive social peers for favorably influencing health-risk behaviors.
Social influences on decision-making are particularly pronounced during adolescence and have both protective and detrimental effects. To evaluate how responsiveness to social signals may be linked to substance use in adolescents, we used functional neuroimaging and a gambling task in which adolescents who have and have not used substances (substance-exposed and substance-naïve, respectively) made choices alone and after observing peers’ decisions. Using quantitative model-based analyses, we identify behavioral and neural evidence that observing others’ safe choices increases the subjective value and selection of safe options for substance-naïve relative to substance-exposed adolescents. Moreover, the effects of observing others’ risky choices do not vary by substance exposure. These results provide neurobehavioral evidence for a role of positive peers (here, those who make safer choices) in guiding adolescent real-world risky decision-making.