Comparing Implicit and Explicit Memory Performance in Symptom-free Depressive Patients Treated with Medication and Normal Individuals

Background and Major depressive disorder is a common, but serious, psychiatric dysfunction that affects 21% of the population worldwide. A first-line treatment for this disorder is pharmacotherapy that affects some clinical symptoms of the disorder, such as low mood, sleep and appetite disturbances, feelings of hopelessness and deficit in memory. Due to inconsistent findings about the efficacy of antidepressants on memory (explicit and implicit), this study aimed at comparing implicit and explicit memory in patients recovered from depression through medication and normal participants. In an ex post facto study, 20 depressive symptom-free patients were selected using convenience sampling. Also, 20 normal individuals were matched for age and sex who were selected based on clinical interviews. To assess implicit and explicit memory performance, free recall test and complement root word were used, respectively. The results revealed no significant differences between the two groups for explicit and implicit memory scores (P>0.05). The present study showed that people on antidepressants who showed improvements in mood, also had normal implicit and explicit memory performance. These findings demonstrate the effect of drugs on cognitive aspects of depression, which of course should be administered with caution