Attentional bias for drug cues in opiate dependence

BACKGROUND: In a number of theories of compulsive drug use conditioned responses to stimuli associated with drug taking play a pivotal role. For example, according to incentive-sensitization theory (Robinson & Berridge, 1993), drug-related stimuli selectively capture attention, and the neural mechanisms underlying this attentional bias play a key role in the development and maintenance of drug dependence, and in relapse. However, there has been little work that assesses attentional biases in addiction. METHODS: We used a pictorial probe detection task to investigate whether there is an attentional bias to stimuli associated with drug use in opiate dependence. Stimuli presented included pairs of drug-related and matched neutral pictures. Methadone-maintained opiate addicts (N = 16) were compared with age-matched controls (N = 16). RESULTS: A mixed design analysis of variance of response times to probes revealed a significant three-way interaction of group x drug picture location x probe location. Opiate addicts had relatively faster reaction times to probes that replaced drug pictures rather than neutral pictures, consistent with the predicted attentional bias to drug-related stimuli. CONCLUSIONS: These results support the idea that an attentional bias for drug-related stimuli occurs in opiate dependence. This is consistent with the concept of a central role for such salient stimuli in compulsive drug use.