Facts and Fiction About Memory Aging: A Quantitative Integration of Research Findings

Abstract

A meta-analytic literature review on adult age differences in speed of search in short-term memory (12 studies), memory span (40 studies), list recall (68 studies), paired-associate recall (21 studies), and prose recall (39 studies) is presented. Results show that age differences are quite large (depending on the task, elderly people can be situated between the 3rd and the 38th percentile of the adult age memory performance distribution) and quasi-omnipresent, even under conditions of cued recall or semantic task orientation. Evidence for age sensitivity is found for the process of categorization of lists, but not for semantic processing, association strategies, imagery, nor for extracting main points from prose material. The elderly population benefits more than the young from the possibility of reviewing lists or texts. Differences between young adults and old-old adults are larger than between young adults and the young-old for speed of search in short-term memory and prose recall only. In two out of the five tasks, lower education is reliably associated with larger age differences.

Shrinkage of the Entorhinal Cortex over Five Years Predicts Memory Performance in Healthy Adults

“…The associations between age and regional volumes follow the pattern observed in previous reports, although the correlation between age and HC volume (especially at follow-up) is somewhat larger than the reported median (for review, see Raz, 2000). The magnitude of age-related memory differences are in the typical range reported in the literature (Verhaeghen et al, 1993).…”

“…Age-related declines in episodic memory are common (Verhaeghen et al, 1993), but their neuroanatomical underpinnings are unclear. Aging differentially affects the putative brain substrates of memory: the hippocampus (HC), the entorhinal cortex (EC), and the prefrontal cortex (PFC) (Squire and Zola-Morgan, 1991;Buckner, 2003).…”

A Meta-Analytic Review of Prospective Memory and Aging.

“…Three other meta-analytic reviews have revealed that (expressed as the standardized differences between younger and older groups) mean age effects for free recall were Ϫ.97 (La Voie & Light, 1994), -.99 (Verhaeghen, Marcoen, & Goossens, 1993), and Ϫ1.01 (Spencer & Raz, 1995). In the present study, the mean effect for free recall expressed as a standardized difference was Ϫ1.22.…”

A diffusion model analysis of adult age differences in episodic and semantic long-term memory retrieval.

“…The hypothesis that aging leads to disproportionate declines in context processing was first formulated in the early 1980s (e.g., Burke & Light, 1981;Rabinowitz & Ackerman, 1982) and continues to be a central theme of research on cognitive aging (e.g., Braver et al, 2001). Age differences in memory tasks tend to increase as a function of the tasks' reliance on memory for contextual detail (for empirical and theoretical reviews, see Light, 1996;2000b;Spaniol & Bayen, 2004;Spencer & Raz, 1995;Verhaeghen, Marcoen, & Goossens, 1993;Zacks et al, 2000). Older adults' poor performance on tasks with high context reliance has been attributed to age deficits in specific cognitive processes such as self-initiated processing (e.g., Craik, 1986Craik, , 1994, recollection (e.g., Jacoby, 1999), or associative encoding (e.g., Naveh-Benjamin, 2000).…”