Priming across modalities and priming across category levels: extending the domain of preserved function in amnesia.

Amnesia is considered to reflect the effects of damage to a specific brain system required for elaboration, consolidation, and conscious recollection. The study of amnesia is therefore a useful approach for establishing dissociations of function and for understanding the normal organization of memory functions. Amnesic patients and two control groups were tested in two studies of priming. In the first experiment, as measured by a word completion test, all groups exhibited significant priming effects that were greater within a modality than across modalities. The amnesic patients exhibited normal priming effects both within and across modalities, despite severe impairment in recall. In the second experiment, all groups exhibited significant and equivalent priming of category exemplars when category labels were presented and subjects were asked to produce the first exemplars that came to mind. The results extend the domain in which preserved priming effects can be observed in amnesia and they suggest that features of priming observed in normal subjects describe a capacity that is independent of the brain system damaged in amnesia.