Attentional bias in methamphetamine users: a visual search task study

Abstract

Attentional bias for drug-related stimuli has been found in users of many types of drugs, which is closely correlated with drug use behaviors. However, such attentional bias in methamphetamine abusers has barely been addressed. The present study explored the attentional bias for methamphetamine-related stimuli in abstinent methamphetamine abusers (abstinent MA participants) and healthy participants. In Experiment 1, 32 abstinent MA participants completed a visual search task designed to assess attentional bias for methamphetamine-related (vs. neutral) pictures. In Experiment 2, 30 healthy participants with no history of drug use were recruited to complete the same task as in Experiment 1. In Experiment 3, 29 abstinent MA participants completed a similar task to examine attentional bias for methamphetamine-related (vs. neutral) pictures that were normal or scrambled. The results showed a decline of performance in MA participants when the methamphetamine-related stimulus appeared as one of the distractors in the search panel (Experiment 1). Such effect disappeared in healthy participants (Experiment 2) or when the methamphetamine-related pictures were scrambled (Experiment 3). The correlation between attentional bias and methamphetamine use behaviors was also investigated and it was found that the bias effect (indexed by response times) significantly positively correlated with years of methamphetamine use. These findings are consistent with the incentive-sensitization model of drug addiction, and support the existence of attentional bias in methamphetamine users. The cognitive task used in the present study may also have implications for intervention and prevention of methamphetamine use and relapse.