The purpose of the present research is to compare the executive-neurological functions between addicted adults and normal adults. This study is a comparative research. The participants of the study consisted of 38 addicts who were referring to two addiction treatment clinics in Tehran, and 38 normal people who were selected through convenient sampling procedure. The participants were examined using the Wisconsin Card Sorting Test. Student t test was used to analyze the data. Statistical analysis showed that there is a significant statistical difference between the executive functions of the addicts and those of normal people. The findings of the present research showed that addicts have weaker executive functions than normal people. In other words, the addicts show impairments in epistemological flexibility and change concepts.
