Memory for action events in Alzheimer-type dementia: further evidence of an encoding failure.

The purpose of the present research was to examine the nature of the encoding problem in patients with dementia of the Alzheimer type (DAT) using a nonstrategic memory task, namely the recall of action events or subject-performed tasks (SPTs). The first experiment investigated the retention of SPTs and the verbal descriptions of action events in patients with mild-to-moderate DAT, young, and old adults. While the healthy older adults showed significantly higher recall for SPTs than for verbal descriptions, the DAT patients failed to exhibit this effect. A follow-up study replicated this same pattern using SPTs and tasks performed by the experimenter. As the multimodal and contextually rich encoding environment present in SPTs had no effect on the patients' retention, this suggests that manipulations designed to enhance encoding in this population will be unsuccessful. The relevance of the results to (1) memory compensation in the aged, and (2) the development of mnemonic training programs for the elderly are discussed.