Brief correspondence: impaired perceptually-based implicit memory in Alzheimer's disease.

Alzheimer's Disease (AD) patients and normal controls were administered three different memory tests: a perceptual implicit memory task (word-fragment completion), a conceptual implicit task (category-association) and an explicit task (recognition). AD patients were outperformed by controls on word-fragment completion but not on the other tasks. Word completion tests may be of use to clinicians involved in memory assessment.