The aim of this research was to investigate the executive functions in two groups of individuals with opioid-dependent, amphetamine- dependent and to compare them with the executive functions in the individuals of the control group. Executive functions were investigated in 4 sub-scales including working memory sustain attention, inhibitory control and planning. To do so, 90 participants were selected via simple nonrandom or convenience sampling. Of these participants, 30 individuals were opioid-dependent, 30 individuals were amphetamine dependent and 30 individuals were healthy. Subjects of the study were evaluated using color-word Stroop, Wisconsin card sorting, continuous performance and digit span sub-scale test. The results of one way analysis of variance indicated significant deficits in amphetamine dependent group in 4 sub-scales of executive functions, but opioid dependent individuals had deficits in inhibitory control and planning compared to the control group. As a result, there were more deficits in the executive functions of amphetamine group in comparison to the opioid-dependent and control group. There were fewer deficits in the opioid-dependent group in comparison to the Amphetamine- dependent group.

Keywords: Executive Functions, Opioid-dependent, Amphetamine dependent