Adolescent Cannabis Users Showed Abnormal Risk-Taking and Reward Brain Patterns Even After Quitting | Research

The takeaway

Abstinent adolescents who had cannabis use disorder showed hyperactivation during risky decisions and reduced reward response in the orbitofrontal cortex, with patterns persisting after treatment remission.

Read this if you are an adolescent or parent wondering whether brain function recovers after cannabis use disorder treatment.

Brain activation differences persisted after remission from cannabis use disorder

What the researchers found

Three groups of male adolescents were compared during a decision-making fMRI task: 15 with cannabis use disorder in remission, 23 controls with other psychiatric conditions, and 18 healthy controls. Abstinent cannabis users showed hyperactivation in parietal/visual regions during risky decisions involving uncertainty, and hypoactivation in the orbitofrontal cortex to rewarded outcomes.

Both control groups differed significantly from the cannabis group (but not from each other) in both decision-making and reward processing. The number of different drug classes tried correlated negatively with orbitofrontal reward response, and cannabis use duration correlated negatively with orbitofrontal response to non-reward.

Why it matters

The persistence of abnormal brain activation patterns after remission from cannabis use disorder suggests that either cannabis caused lasting brain changes or these patterns represent pre-existing vulnerabilities. Either interpretation has implications for understanding adolescent addiction and predicting relapse risk.

The numbers in context

15 CUD remission, 23 psychiatric controls, 18 healthy controls. CUD group: hyperactivation in parietal/occipital during risky decisions. Hypoactivation in OFC to reward. Number of drug classes negatively correlated with OFC reward response. CUD duration negatively correlated with OFC no-reward response.

How the study worked

Cross-sectional fMRI study comparing three groups of male adolescents during the Decision-Reward Uncertainty Task. CUD group in full remission (n=15), psychiatric controls (n=23), healthy controls (n=18). Post-hoc ROI analyses examined correlations between brain activation and substance use variables.

What this study cannot tell us

Small sample sizes, especially the CUD group (15). Cross-sectional design cannot determine whether brain differences preceded or resulted from cannabis use. Only males were studied. The CUD group was in remission, which means some recovery may have already occurred. Other substance exposure could have contributed.

How to read the evidence

Small cross-sectional fMRI study; preliminary evidence for lasting neural effects.

When this study was published

Published in 2013. Research on adolescent addiction neuroscience and brain recovery has expanded.

The bigger picture

This study demonstrates that adolescent cannabis use disorder involves brain circuits beyond the traditional reward system. The abnormal decision-making patterns persisting after remission suggest that vulnerability or lasting effects may predispose adolescents to continued risk-taking and relapse.

Questions still open

Do these brain patterns predict relapse? Would they normalize with longer abstinence? Are they present before cannabis use begins? Could they serve as biomarkers for adolescent addiction vulnerability?

Common questions

Do brain changes from adolescent cannabis use persist after quitting?

This study found that brain activation patterns during decision-making and reward processing remained abnormal in adolescents who had recovered from cannabis use disorder. However, the study cannot determine whether these patterns were caused by cannabis use or existed before use began as a vulnerability factor.

What parts of the brain were affected?

The orbitofrontal cortex, which is critical for evaluating rewards and making decisions, showed reduced activation in response to rewards. This brain region is one of the last to mature during adolescent development, which may make it particularly vulnerable to disruption from substance use during this period.

Read the original research

Neural mechanisms of risky decision-making and reward response in adolescent onset cannabis use disorder.

Drug and alcohol dependence, 133(1), 134-45

View on PubMed ↗Publisher’s paper ↗

Citation

De Bellis, Michael D; Wang, Lihong; Bergman, Sara R; Yaxley, Richard H; Hooper, Stephen R; Huettel, Scott A. (2013). Neural mechanisms of risky decision-making and reward response in adolescent onset cannabis use disorder.. Drug and alcohol dependence, 133(1), 134-45. https://doi.org/10.1016/j.drugalcdep.2013.05.020