Previous research on Alzheimer's disease (AD) has not yielded a consensus regarding the preservation of automatic memory processes, although there is a consensus that conscious recollection processes are impaired in AD.Methods
In the present study, we examined perceptual specificity effects (PSEs) in word recognition judgments (explicit memory task; Experiment 1) and word fragment completion (implicit memory task; Experiment 2) performed by individuals with mild AD and elderly adults without dementia (controls).Results
In recognition judgments, control subjects, but not individuals with AD, demonstrated PSEs (Experiment 1). In contrast, neither group showed PSEs on word fragment completion and their priming magnitudes were comparable (Experiment 2).Conclusions
The findings suggest that perceptually automatic processes in explicit memory judgments and implicit memory processes are different and that the former are specifically impaired in AD.