Older adults with lower autobiographical memory abilities report less age-related decline in everyday cognitive function

Abstract

Background: Individuals differ in how they remember the past: Some richly re-experience specific details of past episodes, whereas others recall only the GIST of past events. Little research has examined how such trait mnemonics, or lifelong individual differences in memory capacities, relate to cognitive aging. We specifically examined trait episodic autobiographical memory (AM, the tendency to richly re-experience episodic details of past events) in relation to complaints of everyday cognitive functioning, which are known to increase with age. Although one might predict that individuals reporting higher trait-level episodic AM would be resistant to age-related decline in everyday function, we made the opposite prediction. That is, we predicted that those with lower trait-level episodic AM would be better equipped with compensatory strategies, practiced throughout the lifespan, to cope with age-related memory decline. Those with higher trait-level episodic AM would have enhanced sensitivity to age-related cognitive changes due to their tendency to rely on their perceived above-average memory function. Methods: We tested these predictions in 959 older adults aged 50-93 using online subjective and objective measures of memory and cognitive function. Our key measures of interest were the Survey of Autobiographical Memory, a measure of autobiographical memory abilities; and the Cognitive Failures Questionnaire, a measure of everyday cognitive function. Results: In keeping with our prediction, we found that complaints of day-to-day memory slips and errors (normally elevated with age) remained stable or even decreased with age among those reporting lower trait-level episodic AM, whereas those reporting higher trait-level episodic AM reported the expected age-related increase in such errors. This finding was specific to episodic AM and not observed for other autobiographical memory capacities (e.g., semantic, spatial). It was further unaccounted for by response bias or objectively assessed cognitive abilities. Conclusions: Congenitally low trait-level episodic AM may paradoxically confer a functional advantage in aging. This could be due to well-developed non-episodic strategies not present in those with higher abilities, who are more sensitive to age-related memory decline attributable to medial temporal lobe changes. Our findings emphasize the importance of considering individual differences when studying cognitive aging trajectories.