MEMORY IMPAIRMENT IN SCHIZOPHRENIA - ITS RELATIONSHIP TO EXECUTIVE FUNCTION

The presence of memory impairment in schizophrenia has frequently been documented but much less attention has been given to the qualitative aspects of this impairment and its association to executive function. Using a cognitive-process approach, we examined memory and executive f unction in 25 patients who met DSM-III-R criteria for schizophrenia. P atients were matched with 25 healthy volunteers. The schizophrenic gro up was found to have a significant impairment in immediate memory, wit h relatively spared long-delay memory. Performance on verbal learning and recognition memory was similar to that of controls. Memory deficit s were present irrespective of the encoding strategies used and were u nrelated to chronicity. In addition, the schizophrenics performed wors e than controls on tests of executive function, but the degree of impa irment was greater on tests of response initiation and suppression. Th is pattern of performance resembled that found in patients with subcor tical or frontal lesions which was supported by some significant corre lations between aspects of memory and executive function. Our results suggest that in schizophrenia, specific executive functions may make a selective contribution to the pattern of memory performance in schizo phrenia which is subserved by frontal and to a lesser extent hippocamp al/diencephalic systems.