Introduction: Sleep is an essential biological function that has a pivotal role in the development of cognitive skills. Sleep disorders make people susceptible to various cognitive and psychological problems. Therefore, this study aimed to Investigate the executive functions in adolescents with sleep disorders. Materials and Methods: The method of the present research was a causal-comparative. The research population consisted of all those who were referred to the health centers and the psychiatric clinic in Tabriz, Iran. 240 adolescents (120 adolescents with sleep disorders and 120 normal adolescents) were selected using available sampling. A sleep disorder checklist (SDS-CL-17) and executive skills questionnaire (ESQ-R) were used to collect data. Results: The results show that adolescents with sleep disorders have more deficiency in all components of executive functions than the healthy group. Conclusion: Our data indicate that sleep disorders make adolescents more susceptible to executive function problems.

Objective: The main aim of the present study is to investigate the executive functions in methadone maintenance patients comparing with two control groups including the abstinent opiate abusers and healthy control subjects. Methods: 25 former opiate addicts receiving methadone maintenance treatments, 25 former opiate addicts withdrawn from all opiates, and 25 healthy controls without a history of drug dependence participated in this study. All groups were matched by age, level of education, and sex. The instruments include Wisconsin Cart Sorting Test, Beck depression Inventory, and State-Trait Anxiety Inventory. Results: The results have showed that there are significant differences on anxiety and depression across three groups, which means that the experimental group obtained high scores than the control groups. The methadone maintenance patients also performed worse than abstinent opiate abusers and healthy controls on WCST. Conclusion: The findings of this study are in line with those of the previous researches which found some neuropsychological impairment in long- term MMP recipients (mintzer and stitzer, 2002 and Lyvers, Yakimoff, 2003 ).