Abstract

Introduction

Adolescence is a development period characterized by a normative increase in the propensity to engage in risky behaviors (e.g., substance use [SU]). From a neurobiological perspective, this propensity may relate to a maturational gap between reward- and control-related neurocircuitry (e.g., limbic and prefrontal circuitry, respectively). The striatum, a prototypical reward-related region, is often highlighted as a particularly critical structure when considering SU outcomes. Among adolescents, both increased as well as decreased striatal activity during reward processing has been linked with future SU. Here, we considered whether reward-related striatal activity, objectively measured task performance, or subjectively reported psychological characteristics predicted future adolescent SU.

Methods

153 adolescents (Mage=14.9±0.7; 53.6% Males; 83.7% Latine) completed W1 of a longitudinal study (involving survey and MRI scan completion) and a follow-up assessment ~15 months later. Baseline measures included self-reported SU (PATH), impulsivity (UPPS-P), and cognitive control (CFQ), along with brain activity during the anticipation phase of a Monetary Incentive Delay (MID) task variant. Logistic regression assessed predictors of nicotine, cannabis, and alcohol use at follow-up.

Results

During win anticipation, increased activity was observed in the bilateral striatum (i.e., caudate) and superior frontal gyrus. During neutral trial anticipation increased activity was observed notably in the insula and anterior cingulate cortex. Increased right striatal activity during win anticipation correlated with faster target reaction times and less self-reported impulsivity. Logistic regression indicated that win-related left striatal activity during anticipation was predictive of future e-cigarette (OR=2.17, 95%CI [1.25-4.09]) and cannabis use (OR=2.74, 95%CI [1.39-5.82]), but not alcohol use (OR=0.87). Baseline SU also predicted use at follow-up, whereas self-reported impulsivity did not.

Conclusions

Elevated striatal reactivity during reward anticipation, rather than impulsivity, emerged as a robust predictor of future adolescent SU. These findings highlight the value of considering neurobiological factors relating to adolescent SU and potential intervention targets to mitigate risk among some vulnerable individuals.