The atypical antipsychotic clozapine causes EEG alterations, and may lead to memory impairments due to its anticholinergic properties. The relationships between clozapine serum level, quantitative EEG parameters and performance in vigilance and memory tasks were studied in a group of 17 chronically ill schizophrenic patients under maintenance treatment with clozapine at stable dosages. There were negative correlations between clozapine serum levels and the amount of high-frequency EEG activity and positive correlations between high-frequency EEG activity and memory performance. These findings may suggest that clozapine treatment brings about dose-dependent impairments of vigilance and memory, for which a reduction of high-frequency EEG activity is indicative.
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Georg AdlerM.D.
Clinical Neurophysiology Service
Central Institute of Mental Health
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