Pure amnesia in a case of right thalamic lesion.

A 50 year old righthanded woman had a sudden attack of disorientation in time and loss of memory. On admission she was found to have a left pyramidal hemisyndrome and a small hypodensity in the right thalamus on CT scanning. Neuropsychological examination revealed a normal short term verbal memory and some impairment of episodic long term memory, which improved after 3 months and normalized completely within a year.