Dataset Information

Effects of Brain Maintenance and Cognitive Reserve on Age-Related Decline in Three Cognitive Abilities.

ABSTRACT:

Objectives

Age-related cognitive changes can be influenced by both brain maintenance (BM), which refers to the relative absence over time of changes in neural resources or neuropathologic changes, and cognitive reserve (CR), which encompasses brain processes that allow for better-than-expected behavioral performance given the degree of life-course-related brain changes. This study evaluated the effects of age, BM, and CR on longitudinal changes over 2 visits, 5 years apart, in 3 cognitive abilities that capture most of age-related variability.

Methods

Participants included 254 healthy adults aged 20-80 years at recruitment. Potential BM was estimated using whole-brain cortical thickness and white matter mean diffusivity at both visits. Education and intelligence quotient (IQ; estimated with American National Adult Reading Test) were tested as moderating factors for cognitive changes in the 3 cognitive abilities.

Results

Consistent with BM-after accounting for age, sex, and baseline performance-individual differences in the preservation of mean diffusivity and cortical thickness were independently associated with relative preservation in the 3 abilities. Consistent with CR-after accounting for age, sex, baseline performance, and structural brain changes-higher IQ, but not education, was associated with reduced 5-year decline in reasoning (β = 0.387, p = .002), and education was associated with reduced decline in speed (β = 0.237, p = .039).

Discussion

These results demonstrate that both CR and BM can moderate cognitive changes in healthy aging and that the 2 mechanisms can make differential contributions to preserved cognition.

SUBMITTER: Gazes Y

PROVIDER: S-EPMC10394982 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature

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Publications

Effects of Brain Maintenance and Cognitive Reserve on Age-Related Decline in Three Cognitive Abilities.

Gazes Yunglin Y Lee Seonjoo S Fang Zhiqian Z Mensing Ashley A Noofoory Diala D Hidalgo Nazario Geneva G Babukutty Reshma R Chen Bryan B BB Habeck Christian C Stern Yaakov Y

The journals of gerontology. Series B, Psychological sciences and social sciences 20230801 8

<h4>Objectives</h4>Age-related cognitive changes can be influenced by both brain maintenance (BM), which refers to the relative absence over time of changes in neural resources or neuropathologic changes, and cognitive reserve (CR), which encompasses brain processes that allow for better-than-expected behavioral performance given the degree of life-course-related brain changes. This study evaluated the effects of age, BM, and CR on longitudinal changes over 2 visits, 5 years apart, in 3 cognitiv ...[more]

PMID: 36882044

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Dataset Information

Effects of Brain Maintenance and Cognitive Reserve on Age-Related Decline in Three Cognitive Abilities.

Objectives

Methods

Results

Discussion

Publications

Effects of Brain Maintenance and Cognitive Reserve on Age-Related Decline in Three Cognitive Abilities.

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