Summary.—In this study, to investigate the right or left ear advantages in psychiatric patients, the durations of hearing for right and left ears were assessed in 61 psychiatric patients, 26 with schizophrenia, 17 with depressive disorder, 13 with bipolar affective disorder, and 5 with brief psychotic disorder, plus 24 controls. Diagnoses were made on the basis of information provided from clinical interviews and the Structured Clinical Interview for DSM-IV (SCID). Schizophrenia was associated with a left ear advantage, and both depressive disorder and brief psychotic disorder were associated with right ear advantage as well as controls. These results suggest that their schizophrenia may be associated with a left temporal lobe dysfunction.