Effects of Healthy and Neuropathological Aging on Autobiographical Memory: A Meta-Analysis of Studies Using the...

A meta-analytic review was conducted to assess the effects of healthy aging, amnestic mild cognitive impairment (MCI), and Alzheimer's disease (AD) on naturalistic autobiographical memory using the Autobiographical Interview, a widely used, standardized assessment that derives measures of internal (episodic) and external (nonepisodic) details from freely recalled autobiographical narratives.

A comprehensive literature search identified 21 aging, 6 MCI, and 7 AD studies (total N = 1,556 participants). Summary statistics for internal and external details for each comparison (younger vs older or MCI/AD vs age-matched comparison groups) and effect size statistics were extracted and summarized using Hedges' g (random effects model) and adjusted for the presence of publication bias.

The pattern of reduced internal and elevated external details in aging was robust and consistent across nearly all 21 studies. MCI and-to a greater extent-AD were associated with reduced internal details, whereas the external detail elevation faded with MCI and AD. Although there was evidence of publication bias on reporting of internal detail effects, these effects remained robust after correction.

The canonical changes to episodic memory observed in aging and neurodegenerative disease are mirrored in the free recall of real-life events. Our findings indicate that the onset of neuropathology overwhelms the capacity of older adults to draw upon distributed neural systems to elaborate on past experiences, including both episodic details specific to identified events and nonepisodic content characteristic of healthy older adults' autobiographical narratives.