Event-related potentials and thought disorder in schizophrenia

We examined the relationship between event-related potentials and thought disorder in schizophrenia. The subjects were 29 chronic schizophrenic patients. Thought disorder was assessed using the Comprehensive Index of Positive Thought Disorder developed by Harrow and colleagues (Harrow, M., Quinlan, D., 1985. Disordered Thinking and Schizophrenic Psychopathology. Gardner Press, New York; Marengo, J.T., Harrow, M., Latin Kettering, L., Wilson, A., 1986. Evaluating bizarre-idiosyncratic thinking: a comprehensive index of positive thought disorder. Schzophr. Bull. 12, 497-511). Auditory event-related potentials were recorded during a standard oddball task. The P300 amplitude correlated negatively with the severity of the thought disorder. The P300 amplitude in the patients with thought disorder was significantly smaller than in the patients without thought disorder. These results suggest that a reduction in P300 amplitude is associated with a fundamental impairment of information processing in schizophrenic patients. (C) 2000 Elsevier Science B.V. All rights reserved.