Thirty-three inpatients (22 male, 11 female) at New York State Psychiatric Institute were recruited for the study, excluding left-handed individuals and those with a history of neurological illness or substance abuse. Data from 10 patients (7 male, 3 female) were excluded from the study due to an insufficient number of correct, artifact-free trials (at least 14 for any target condition) or a low signal-to-noise ratio, which prevented a recognizable ERP component structure in the individual waveforms. The 23 patients included in the final patient sample met DSM-IV58 criteria for schizophrenia (paranoid, n = 11; undifferentiated, n = 6; disorganized, n = 1) or schizoaffective disorder (depressed type, n = 3; bipolar type, n = 2). Diagnoses were based on clinical interviews by psychiatrists and a semistructured interview59 including items from commonly-used instruments (e.g., SCID-P; SANS, SAPS).60–62 Symptom ratings were obtained using the Positive and Negative Syndrome Scale (PANSS).63 The total brief psychiatric rating scale (BPRS) score indicated that patients were mildly-to-moderately disturbed (Table 1). Most patients (n = 13) did not receive antipsychotic medications for at least 14 days before
