[A case of left internal capsular infarction with auditory hallucination and peculiar amnesia and dysgraphia].

A 46-year-old businessman suddenly became to behave curiously on the morning, September 1, 1988. He forgot how to go through an automatic ticket gate, which he used every day. In his company, he also forgot how to open the cash box, and he wrote a meaningless report for his business. From the night on that day, he had experienced auditory hallucination in which whispering words of some criticism to his performance for a few days. On the next day, he was admitted to a psychiatric hospital because he was suggested to have schizophrenia. By day 6 after the onset, his curious symptoms completely disappeared. However, slight verbal memory disturbance and cognitive dysfunction still remained. Because the brain CT on day 6 showed a small localized subcortical infarction in the left hemisphere he was transferred to our clinic on day 20 to elucidate the relation between the abnormal behavior and the infarction. His blood pressure was 116/64 mmHg and pulse was regular 63/min. He was clear and did not have any neurological deficit. He kept his episodic memory regarding the events at the onset and could almost recall them precisely. Results of standard blood tests, electrocardiogram, ultrasound cardiogram, electroencephalogram as well as cerebral angiography were normal. Computed tomography and magnetic resonance imaging showed an infarcted lesion in the genu of the left caudate nucleus, adjacent to the anterior part of the thalamus.(ABSTRACT TRUNCATED AT 250 WORDS)