Abstract
Based on the analysis of recovery process in patients with tansient grobal amnesia, there were periods during which patients had anterograde amnesia without retrograde amnesia ( ‘isolated anterograde amnesia’ ). We also presented two cases of isolated retrograde amnesia resulting from probable encephalitis. Taken together, it seems that anterograde amnesia and retrograde amnesia may be exist independently and produced anatomically different structures.
A case with circumscribed temporal atrophy show impairment of social memory with relatively unaffected autobiographical memory. Patients with Alzheimer's disease show defect of both social memory and autobiographical memory with temporal gradient. Social memory and autobiographical memory may be impaired independently.
Analysis of cases with isolated retrograde amnesia and neurodegenerative diseases led us to the following speculations that the responsible lesion for retrograde amnesia is within the temporal lobe.
