Patients with schizophrenia will be recruited from the inpatient population of the NIMH Wards at the NIH Clinical Center and the sibling study protocol 95-M-0150. Diagnoses will be made by the NIMH clinical staff in accordance with DSM-IV(R). Patients with history of neurological illness other than those of interest to the study, or other medical illness or surgery that might have impact on the study of brain physiology, will be excluded. Inpatients on the NIMH Schizophrenia Ward who have signed protocol 89-MH-160 "Inpatient Evaluation of Neuropsychiatric Patients) will be studied when they have been withdrawn from all medications for two to four weeks. They will also be studied when they are stabilized on medication; however, no treatment decisions, for inpatients or outpatients, will be based upon this study. All inpatients will be carefully monitored on the NIMH/NIH wards as per protocol 89-MH-160.