Forty-eight undrugged hospital admissions with a present state examination (PSE) diagnosis of schizophrenia were subdivided by the direction of lateral differences in electrodermal response amplitudes to tones. The 29 with larger right-hand responses and the 19 with larger left-hand responses were compared on CATEGO syndromes and brief psychiatric rating scale (BPRS). The larger group had symptoms like those of classical Bleulerian schizophrenia--blunted affect, emotional withdrawal, impaired social functioning, disorganized thought and retarded motility. The other group manifested florid symptoms including hypomanic affect, pressure of speech, ideas of reference, depressive hallucinations and delusions, hypochondriasis, grandiosity and situational anxiety. The psychophysiological measures may provide an objective aid to diagnosis and implications for altered cerebral organization in psychotic patients.