Neural synchronization may have a critical role in the integration of information within and across cerebral structures. Synchronization, particularly at gamma range frequencies, is thought to be dependent on GABAergic interneurons, which may be disturbed in schizophrenia. We report that patients with schizophrenia show severe disruption of electroencephalogram (EEG) measures of neural synchronization to periodic auditory and visual stimulation. Both EEG power and phase synchronization to temporally modulated signals were affected in the beta or gamma frequency ranges. These findings are consistent with GABAergic dysregulation in schizophrenia, which disrupts neural synchronization. A deficit in neural synchronization at high firing frequencies could contribute to behavioral disturbances of perceptual and temporal integration observed in this disorder.