Cognitive functions in tardive dyskinesia.

Cognitive functions of psychiatric patients with and without tardive dyskinesia were evaluated using the Wechsler Adult Intelligence Scale, Wechsler Memory Scale and Rey Auditory Verbal Learning Test. Schizophrenic patients with and without tardive dyskinesia did not differ in their performance on the administered psychological tests. However, affective disorder patients with tardive dyskinesia showed significantly more impairment on the Wechsler Memory Scale and Rey Auditory Verbal Learning Test than affective disorder patients without tardive dyskinesia. These findings suggest that affective disorder patients who develop tardive dyskinesia may have some predisposing brain damage or that tardive dyskinesia in these patients represents both a motor and a dementing disorder.