Differential effects of aging on explicit and implicit memory

Abstract

In the present study, five consecutive age groups ranging from the 20s to the 60s were compared on a range of explicit and implicit memory tests which were modelled on the clinical tasks used to assess amnesia. With respect to explicit memory, the ability to recall verbal or visual material was seen to decline steadily with increasing age at immediate and delayed testing; there were, however, no consistent age differences regarding performance on recognition tasks. Perceptual skill acquisition within the context of a mirror reading task was unaffected by age, while word stem completion priming tended to decline across the age groups. Factor analysis revealed three factors: verbal explicit memory, visual memory (comprising visual recall and stem completion priming), and skill acquisition. the present findings indicate dissociable effects of normal aging on explicit and implicit memory, and thereby some degree of qualitative resemblance to human amnesia.