A systematic review of electrophysiological markers of reward processing in addiction.

In 30 seconds

This systematic review examined EEG event-related potential markers of reward anticipation and outcome processing in adults with substance use disorders or behavioral addictions, compared with healthy controls. It included 42 studies: 23 on substance use disorders and 19 on behavioral addictions. Across studies, altered neural responses appeared at multiple stages of reward processing, including anticipation and early and late responses to outcomes. The findings were consistent with disruptions in generating, evaluating, and updating reward expectations, although methodological heterogeneity limits the strength of conclusions.

Key findings

• The review included 42 studies: 23 on substance use disorders and 19 on behavioral addictions.
• Altered electrophysiological responses were reported across reward anticipation and early and late reward-outcome processing.
• The reviewed patterns were consistent with disruptions in generating, evaluating, and updating reward expectations.

Why it matters

Reward processing is relevant to understanding how addictive behaviors may persist despite adverse consequences. This review brings together electrophysiological findings across substance and behavioral addictions and across distinct processing stages, while emphasizing that differences in study methods make the evidence difficult to compare and interpret confidently.

What to keep in mind

Methodological heterogeneity across the reviewed studies limits the strength of conclusions.