Elaborated spaced-retrieval and prospective memory in mild Alzheimer's disease

Abstract

Prospective memory, or the timely remembering of a planned action, is conceptualised as a cognitive process demanding episodic memory and executive attention. Impairments in these skills are characteristic of the cognitive decline in early Alzheimer's disease, providing an expectation of prominent prospective memory difficulties in this population, and yet surprisingly, memory performance in early Alzheimer's disease has rarely been evaluated within a prospective memory framework. In a preliminary study we demonstrated that older adults with early Alzheimer's disease (n = 14), as compared to healthy older adults (n = 14), were significantly impaired in a simple experimental paradigm of prospective remembering (a text-reading task). In a subsequent intervention study, we investigated the efficacy of spaced-retrieval for improving the prospective remembering performance of older adults with early Alzheimer's disease (n = 16) compared to healthy older adults (n = 16) under two learning conditions: a spaced-retrieval technique alone or spaced-retrieval combined with elaborated encoding of task. The majority of the Alzheimer's disease group (63%) demonstrated benefit in prospective remembering in the combined condition as compared to spaced-retrieval alone. Participants with Alzheimer's disease who demonstrated better executive attention (Trail Making – set-shifting) and/or better retrospective memory (Hopkins Verbal Learning Test–Revised – recognition) were more successful in the combined learning condition.

This research was supported by a La Trobe University Central Research grant. The authors would like to thank the participants who took part in the study and to acknowledge the assistance provided by Cheryl Scott, Memory Clinic Co-ordinator, Austin and Repatriation Medical Centre and Janine Melville, Memory Clinic Co-ordinator, Southern Health, and Community Care, Bayside Health. A brief version of this paper was presented at the ASSBI/INS conference in Brisbane, Australia, June 2004.