Hemispheric asymmetry in visual recognition of words and motor response in schizophrenic and depressive patients

Two-letter Hangul words were presented tachistoscopically as target words to either the right or left visual field of normal subjects, schizophrenics, and depressive patients. The subjects' task was to judge the similarity or difference between the target words and the words used for comparison. They were to signal as soon as possible by pressing a key with their hands. In normal subjects, the correct response rate was significantly higher in the left hemisphere; there was little difference in the speed of motor response between the two hemispheres, however. Compared with normal subjects, both patient groups showed generalized impairment. Schizophrenia was associated with impairment in the left hemisphere, depression was associated with impairment in the right hemisphere.