comparison of behavioral activation subscales of gray’s original reinforcement sensitivity theory in opioid and methamphetamine dependent patients

Introduction: the relationship of behavioral activation subsystems with methamphetamine and opioids dependency, which are the most commonly used illicit substances in iran, is still unclear. the purpose of this study was to compare the behavioral activation subsystems and behavioral inhibition system of opioid and methamphetamine dependents with those of healthy subjects. materials and methods: in this casecontrol study, two groups of methamphetamine and opioids dependents (25 cases on each group) were selected through purposeful method from patients admitted to substance rehabilitation centers of mashhad, iran, during march to september 2012. a group of 25 healthy cases (nonaddict) were also matched as the control group. data was collected using carver and white’s bas/bis scales and analyzed using chisquare test, oneway analysis of variance, and multivariate analysis of variance. results: the methamphetaminedependents group had a higher basdr subscale score than the opioid dependent group (p<0.01), but in neither group these scores were significantly different from the basdr scores of healthy subjects (p>0.05). the basrr scores of the methamphetaminedependents group were higher than the other two groups (p<0.05). the scores of basfs subscale of the control group was higher than in the opioiddependent group (p<0.05), but was no difference from the scores of methamphetaminedependent patients (p>0.05). there was no difference between the three groups in terms of scores of behavioral inhibition system (p<0.05).  conclusion: the difference of bas subscales of patients with different substance dependencies from those of healthy subjects confirms the role of reward deficiency syndrome in the substance use disorder. also, methamphetamine and opioid dependencies were found to have a durationdependent impact on the behavioral activation subsystems.