Preserved semantic access in global amnesia and hippocampal damage.
C.B., a right-handed 33-year-old man, presented with anterograde amnesia after acute heart block. Cognitive abilities were normal except for serious impairment of long-term episodic memory. The access to semantic information was fully preserved. Magnetic resonance showed high signal intensity and marked volume loss in the hippocampus bilaterally; the left and right parahippocampal gyrus, lateral occipito-temporal gyrus, inferior temporal gyrus, and lateral temporal cortex were normal. This case underlines that global amnesia associated with hippocampal damage does not affect semantic memory. Although the hippocampus is important in retrieving context-linked information, its role is not so crucial in retrieving semantic contents. Cortical areas surrounding the hippocampus and lateral temporal areas might guide the recall of semantic information.
Giovagnoli
A R
AR
Laboratory of Neuropsychology, Department of Neuropathology and Neurology, Istituto Nazionale Neurologico Carlo Besta, Milano, Italy. rgiovagnoli@istituto-besta.it
Erbetta
A
A
Bugiani
O
O
D000328:Adult; D020324:Amnesia, Anterograde / Q000209:etiology*; D001930:Brain Injuries / Q000150:complications*; D006624:Hippocampus / Q000293:injuries* / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D012660:Semantics; D012720:Severity of Illness Index