Study of Cognitive Functions of Continuous Attention, Decision-Making and Response Inhibition in Subjects withMethamphetamine Dependence

Background and Objectives: Drug abuse can have long- and short-term effects on the cognitive function of individuals due to changes in brain structure and function. These effects often manifest themselves in the form of chronic and acute neuropsychological abnormalities. The purpose of this study was to investigate several cognitive functions, i.e., continuous attention, decision-making, and response inhibition in methamphetamine-dependent individuals   Methods: A total of 42 patients with methamphetamine dependence as patient group and 38 employees of Forghani Hospital in Qom city as control group, were selected using convenience sampling. The research sample carried out continuous performance, Iowa risk taking and color-word Stroop tasks tests.   Results: Multivariate analysis of variance showed that there was a significant difference between patients and healthy groups in terms of continuous performance, Iowa risk taking and color-word Stroop tasks. The difference in these tests, was in such a way that the healthy group performed better compared to the patients in terms of assignment error response (p = 0.018), removal (p = 0.049), fine (p = 0.039), interruption time (p = 0.030), and interference score (p = 0.043).   Conclusion: This study indicated that methamphetamine has a serious effect on a number of cognitive functions, which leads to disruption in many other psychological functions in these individuals. Failure in decision making and inhibition to control consumption, aggressive and impulsive behaviors, learning deficits, lack of reasoning, and the ability to make the right decisions in personal, educational, occupational, and interpersonal areas are a few of these cases.