Working Memory in Schizophrenia as Revealed by Event-Related Potentials

Abstract

In this study, we compared working memory (WM) functions for simple actions of healthy subjects and schizophrenic patients by means of behavioral and ERP measures. Healthy subjects showed a large frontal N2 amplitude in the hard WM task with updating demands of temporal sequence, but not in the easy WM and the control task. Schizophrenic patients had large frontal N2 amplitudes in all tasks without difference indicating that the patients had to activate the frontal cortex in tasks in which healthy subjects use automatized routines which do not involve the frontal cortex. Strong negative symptoms in schizophrenic patients were associated with small N2 amplitudes thus supporting the hypothesis of joint causes of cognitive and psychopathological features.