Comparison of behavioral activation subscales of Gray's original reinforcement sensitivity theory in opioid and methamphetamine dependent patients

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.
In this case-control 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 (non-addict) were also matched as the control group. Data was collected using Carver and White’s BAS/BIS scales and analyzed using Chi-square test, one-way analysis of variance, and multivariate analysis of variance.
The methamphetamine-dependents group had a higher BAS-DR subscale score than the opioid dependent group (P0.05). The BAS-RR scores of the methamphetamine-dependents group were higher than the other two groups (P0.05). There was no difference between the three groups in terms of scores of behavioral inhibition system (P 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 duration-dependent impact on the behavioral activation subsystems.