Is implicit memory preserved in Alzheimer's disease? Implications for theories of implicit memory

Theories of implicit memory were formulated largely on data from temporal lobe amnesics. This review examines the generalizability of those findings and theories to individuals with Alzheimer's disease. Although these groups have similar explicit memory impairments, their performance on implicit memory tests differs in systematic and theoretically meaningful ways. Whereas amnesics show preserved implicit memory across a variety of tasks, individuals with probable Alzheimer's disease generally show preserved implicit learning and perceptual priming, but impaired conceptual priming. Findings are discussed in partial support of a transfer-appropriate processing view, and suggestions are made for future research.