Educational Attainment Moderates the Association Between Hippocampal Volumes and Memory Performances in Healthy Older Adults

Abstract

Objective: To examine whether educational attainment, as a proxy of cognitive reserve, moderated the association between hippocampal volumes and episodic verbal memory performances in healthy older adults.Methods: Data from 76 community dwelling older adults were included in the present study. Measures of hippocampal volumes (total, left, and right) were obtained using FreeSurfer software. Immediate and delayed verbal recall scores were derived from performances on the California Verbal Learning Test-Second Edition and the Wechsler Memory Scale- Third Edition. Educational attainment was defined by years of education. Linear regression analyses were performed using immediate and delayed recall as dependent variables and hippocampal volumes, years of education, and their interaction terms as independent variables. All analyses were controlled for age, sex, depression, and health status.Results: Total and left Hippocampal volumes had a positive main effect on delayed recall only. Additionally, the interaction between total, left, and right hippocampal volumes and education was a significant predictor for delayed recall performance but not for immediate recall performance. The positive association between hippocampal volumes and delayed recall was greatest in those with more years of education.Conclusion: Larger hippocampal volumes were associated with better delayed verbal recall and the effect on delayed recall was greatest in those with more years of education. Having higher levels of education, or cognitive reserve, may enable individuals to capitalize on greater structural integrity in the hippocampus to support delayed recall in old age. However, longitudinal research is needed to investigate the directionality of these associations.

Moderating effect of cognitive reserve on the association between grey matter atrophy and memory varies with age in older adults

“…However, previous studies of normal aging population found mixed or contradicting results in how educational attainment or proxies of CR alter the association between GMV and cognitive functioning. For example, two studies specifically showed that age‐related GMV variation was positively associated with cognitive functions and such a relationship was stronger in higher CR elderly individuals . Similar or null results were reported in other studies examining the moderating role of CR, showing a stronger association between pathological impact and cognitive functions in higher CR elderly .…”

Face–Name Associative Memory Performance Among Cognitively Healthy Individuals, Individuals With Subjective Memory Complaints, and Patients With a Diagnosis of aMCI

“…Previous research have found that the face–name associative memory performance was not affected by education level in contrast to traditional memory measures (Werheid and Clare, 2007 ; Amariglio et al, 2012a ; Alegret et al, 2015 ; Kormas et al, 2018 ). Highly educated individuals are characterized by rich semantic networks, and they have the ability to develop advanced and sophisticated conceptual strategies that positively contribute to the recall of word lists and/or stories (O'Shea et al, 2018 ). In this context, clinical studies have found that higher education improves CRs (Thow et al, 2018 ), and individuals with higher levels of CR are able to compensate a higher degree of brain dysfunction (Corral et al, 2006 ).…”

The associations of the BDNF and APOE polymorphisms, hippocampal subfield volumes, and episodic memory performance across the lifespan

“…Education-levels can moderate the association between hippocampal volumes and memory performance (O'Shea et al, 2018). Therefore, all analyses involving memory performance across APOE polymorphisms were adjusted to account for the observed differences in education years.…”