PERSISTENT RECURRENCE OF HYPOMANIA AND PROSOPOAFFECTIVE AGNOSIA IN A PATIENT WITH RIGHT THALAMIC INFARCT

The authors report a 63-year-old man with a history of brief isolated manic episodes who became persistently hypomanic after a small light t halamic infarct. Detailed behavioral and neuropsychologic assessment w ere performed 18 months after the stroke and revealed a prosopoaffecti ve agnosia as the foremost cognitive disorder, i.e., an impairment in the identification of emotional facial expressions with preserved disc rimination of facial identity. Difficulties in reasoning on humorous m aterial and other signs of mild right hemisphere dysfunction were pres ent, but other perceptual, frontal, and abstract-reasoning cognitive f unctions were unimpaired. Prosopoaffective agnosia has not been report ed previously in thalamic lesions or in primary or secondary mania. Th e authors discuss the hypothetical relationships between a right hemis phere deficit in processing emotions and relapsing of the patient's hy pomanic behavior.