Amnesic syndrome: a lesion-specific disorder?

This paper reviews various lines of evidence which suggest that organic amnesia stemming from lesions of the temporal lobe region produce an amnesia that is qualitatively different from that produced by diencephalic lesions. Differences between these two classes of amnesia were found within five dimensions of performance; (a) insight, concern and confabulation, (b) retrograde amnesia, (c) forgetting rate, (d) frontal lobe symptoms, (e) sensitivity to interference in short term memory. The range of differences found suggest that temporal lobe and diencephalic amnesics should not be considered as suffering from the same type of "amnesic syndrome". It is proposed that future experimental work on amnesia should take full account of neuropathological differences between amnesic patients.