DIFFERENTIAL-EFFECTS OF EARLY HIPPOCAMPAL PATHOLOGY ON EPISODIC AND SEMANTIC MEMORY

Global anterograde amnesia is described in three patients with brain i njuries that occurred in one case at birth, in another by age 4, and i n the third at age 9. Magnetic resonance techniques revealed bilateral hippocampal pathology in ail three cases. Remarkably, despite their p ronounced amnesia For the episodes of everyday life, all three patient s attended mainstream schools and attained levels of speech and langua ge competence, literacy, and factual knowledge that are within the low average to average range. The findings provide support for the view t hat the episodic and semantic components of cognitive memory are partl y dissociable, with only the episodic component being fully dependent an the hippocampus.