BRAIN ATROPHY AND INTELLECTUAL IMPAIRMENT IN TARDIVE-DYSKINESIA

Fourteen chronic schizophrenic patients with tardive dyskinesia (TD) a nd 13 without TD were given psychological tests and CT scans. The low density rate (LDR), i.e., the ratio of the X-ray absorption (correspon ding nearly to that of cerebrospinal fluid) of a brain lesion to the X -ray absorption of the whole brain, was used as an index of brain atro phy (HN-method). The LDR of the left hemisphere of the TD patients was significantly higher than that of non-TD patients in the basal nucleu s and lateral ventricle, and the LDR of the right hemisphere for the T D patients was significantly higher than that of non-TD patients in th e basal nucleus. The Hasegawa Dementia Rating Scale (HDRS) and Bender- Gestalt Test (BGT) for the TD patients were significantly lower than t hose for the non-TD patients. Our study revealed that brain atrophy wa s greater in TD than in non-TD patients and tended to be more pronounc ed in the left hemisphere, and that the degree of intellectual impairm ent was greater in the TD patients than in the non-TD group. The resul ts suggest that schizophrenic brains with TD tend to be more easily da maged than those without TD, that this tendency predominates on the le ft side, and that intellectual impairment in TD is related to brain at rophy.