Prospective memory impairments in schizophrenic patients.

Objective: Memory impairment is one of the most pervasive cognitive dysfunctions in schizophrenic patients. The aim of the current study was to conduct the most comprehensive assessment of how prospective memory (PM) is affected in schizophrenia in comparison with healthy controls.

Methods: In this study, 30 first-episode schizophrenic patients who fulfilled the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders based on the diagnostic interview were recruited from eight regional psychiatric clinics in Iran. All participants were males (age 27-42). Moreover, 28 healthy controls were recruited from the same social-class as the patients. The Prospective and Retrospective Memory Questionnaire (PRMQ), PM tasks, and the Virtual Week Board Game were administered. Moreover, clinical symptoms were rated using the positive and negative symptoms scale.

Results: The results showed that in all of the memory types, the group with dominant positive symptoms was superior to the group with dominant negative symptoms. In addition, the results showed that in all of the memory types, the control group had superiority to the schizophrenic group. The most considerable differences between groups were in time-based PM tasks, irregular event-based virtual week tasks, and retrospective tasks (PRMQ).

Conclusion: The current study confirmed that schizophrenic patients have severe PM deficits.