Persistent memory impairment following transient global amnesia.

A controlled neuropsychological study of 41 patients tested at 6 months after attacks of transient global amnesia (TGA) revealed no evidence of general intellectual, immediate (short-term) memory or nonverbal memory impairment. The patient group's performance was, however, significantly worse than that of the control's on measures of verbal memory notably immediate, 30-minute and 24-hour delayed paragraph recall. In addition, tests of public and personal remote memory revealed significant impairment of naming and recognition of famous faces, and of dating famous events without evidence of a temporal gradient, and impairment of cued recall of autobiographical memories on the Modified Crovitz Test. These findings suggest that following TGA there is persistent, albeit mild, hippocampal-diencephalic dysfunction which appears to involve left-sided structures preferentially. This impairment probably results from the attack, although a pre-existent deficit cannot be excluded.