The relationship between the duration and rate of drug use and explicit / implicit memory bias among opium and stimulant addicts

Introduction: Today, drug abuse as a multifaceted phenomenon has become one of the main problems in societies and has taken different forms. Aim: The present study aims to examine the relationship between the duration and the rate of drug use and explicit/ implicit memory bias among opium and stimulant addicts. Method: The study design was a casual-comparative study. The statistical population included all opium and stimulant addicts in Takab city in 2018, that 30 opium addicts and 30 stimulant (methamphetamine) addicts were selected by available sampling and were homogenized in terms of some demographic variables. The research instruments included a computerized explicit memory, a computerized word base completion test, an unstructured clinical interview, and a demographic information questionnaire. Statistical data were analyzed by descriptive statistics, Pearson correlation coefficient, t -test and SPSS-17 software. Results: The results showed that there is a relationship between the drug use duration and explicit/ implicit memory bias in opium (r=+0.68) and stimulant addicts (r=+0.79) and also between rate of drug use and explicit/ implicit memory bias in opium (r=+0.73) and stimulant addicts (r=+0.81, P<0.05). In other words, with an increase in the duration and rate of drug use, the opium and stimulant addicts showed signs of higher explicit/ implicit memory bias even though stimulant addicts showed greater memory bias than the opium addicts (P<0.05). Conclusion: Emphasis on cognitive processes including memory bias among drug addicts, is one of the solutions to consider in prevention and clinical treatment interventions.