Neural recruitment and connectivity during emotional memory retrieval across the adult life span

Abstract

Although research has identified age-related changes in neural recruitment during emotional memory encoding, it is unclear whether these differences extend to retrieval. In this study, participants engaged in a recognition task during a functional magnetic resonance imaging scan. They viewed neutral titles and indicated whether each title had been presented with an image during the study phase. Neural activity and connectivity during retrieval of titles associated with positive and negative images were compared with age (treated as a continuous variable) included as a regressor of interest. Aging was associated with increased prefrontal activation for retrieval of positive and negative memories, but this pattern was more widespread for negative memories. Aging also was associated with greater negative connectivity between a left hippocampal seed region and multiple regions of prefrontal cortex, but this effect of age occurred during negative retrieval only. These findings demonstrate that age-related changes in prefrontal recruitment and connectivity during retrieval depend on memory valence. The use of a life span approach also emphasized both continuities and discontinuities in recruitment and connectivity across the adult life span, highlighting the insights to be gained from using a full life span sample.

Keywords: Aging; Connectivity; Memory; Prefrontal cortex; Retrieval; fMRI.