BackgroundOne of the most prominent theories of drug addiction is the incentive sensitization model. Individual differences in the tendency to ascribe motivational salience to cues that predict reward, and their ability to promote reward-seeking behaviour have been identified as potentially important in understanding vulnerability to addiction and relapse. However, to date this behaviour has not been assessed in a treatment-seeking clinical population, highlighting a significant gap in the literature pertaining to incentive sensitization and drug addiction.MethodsIndividuals accessing drug and alcohol services with alcohol as primary drug of concern were recruited to participate in an intervention study. At the baseline session, participants completed various self-report measures (including the Alcohol Use Disorders Identification Test; AUDIT) in addition to a visual search task measuring sign-tracking to cues predicting monetary reward. Self-reported abstinence at 3-month follow up was primary outcome measure. All analyses and hypotheses were pre-registered.ResultsAt baseline (49 participants), AUDIT scores correlated with sign-tracking to signals of monetary reward, a relationship that cannot be explained by overall response time in the task or demographic variables. Sign-tracking, gender and craving during the sessions predicted return to use at 3-month follow up (41 participants). ConclusionsOur work demonstrates that involuntary sign-tracking to cues signalling non-drug reward is associated with problematic alcohol use and return to use at 3-month FU, in a treatment-seeking sample. Whether this automatic prioritisation of cues signalling reward is a consequence or vulnerability for problematic drug use remains to be seen.