Understanding associative false memories in aging using multivariate analyses

Abstract

Associative memory declines in aging arise, in part, from age-related increases in false memories to recombined lures. Studies have shown that there is a benefit to associative memory if the configural context of associative pairs is maintained from encoding to retrieval. The current study aimed to examine whether this benefit of contextual congruency is reduced in aging, and whether the neural similarity of memory representations between targets and lures underlies age- related increases in false memories. Behaviorally, both age groups benefited from target pairs presented in a visual format that was congruent with how the pair was learned. While no age difference was observed in hits, the typical age-related increase in false alarms was found. Congruent with behavioral results, neither the relationship between target-related patterns of neural activity across memory phases (as measured by ERS) nor the discriminability of target classification as a function of condition at retrieval (as measured by MVPA). However, with regard to false memories, older adults exhibited overall lower pattern similarity for hits and FAs compared to hits and CRs (as measured by RSA). Additionally, Hit-FA RSA correlated with age- related increases in associative FAs across visual, frontal, and parietal cortices. Results suggest that while neural processes supporting associative memory retrieval are dependent on configural congruency between encoding and retrieval, there is no difference as to how congruency affects these processes in aging. Additionally, similarity of target and lure processing may reflect reduced diagnosticity of information processing in aging.