Aetiological variation in the amnesic syndrome: comparisons using the list discrimination task.

In this study, the performance of amnesic patients with presumed temporal lobe damage was compared with that of patients with presumed diencephalic damage using the temporal list discrimination task. The two patient groups performed similarly on a measure of recognition, but the diencephalic group was impaired relative to the temporal lobe group on a measure of temporal discrimination. Discrimination performance in the temporal lobe group was significantly correlated with recognition memory. The data are interpreted as showing a qualitative difference in the form of amnesia arising from damage centred on the medial temporal lobes compared with that centred on the midline diencephalon.