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Functional network structure supports resilience to memory deficits in cognitively normal older adults with amyloid-β pathology.

ABSTRACT: Older adults may harbor large amounts of amyloid-β (Aβ) pathology, yet still perform at age-normal levels on memory assessments. We tested whether functional brain networks confer resilience or compensatory mechanisms to support memory in the face of Aβ pathology. Sixty-five cognitively normal older adults received high-resolution resting state fMRI to assess functional networks, 18F-florbetapir-PET to measure Aβ, and a memory assessment. We characterized functional networks with graph metrics of local efficiency (information transfer), modularity (specialization of functional modules), and small worldness (balance of integration and segregation). There was no difference in functional network measures between older adults with high Aβ (Aβ+) compared to those with no/low Aβ (Aβ-). However, in Aβ+ older adults, increased local efficiency, modularity, and small worldness were associated with better memory performance, while this relationship did not occur Aβ- older adults. Further, the association between increased local efficiency and better memory performance in Aβ+ older adults was localized to local efficiency of the default mode network and hippocampus, regions vulnerable to Aβ and involved in memory processing. Our results suggest functional networks with modular and efficient structures are associated with resilience to Aβ pathology, providing a functional target for intervention.

SUBMITTER: Adams JN

PROVIDER: S-EPMC10457346 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature

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Functional network structure supports resilience to memory deficits in cognitively normal older adults with amyloid-β pathology.

Adams Jenna N JN Chappel-Farley Miranda G MG Yaros Jessica L JL Taylor Lisa L Harris Alyssa L AL Mikhail Abanoub A McMillan Liv L Keator David B DB Yassa Michael A MA

Scientific reports 20230825 1

Older adults may harbor large amounts of amyloid-β (Aβ) pathology, yet still perform at age-normal levels on memory assessments. We tested whether functional brain networks confer resilience or compensatory mechanisms to support memory in the face of Aβ pathology. Sixty-five cognitively normal older adults received high-resolution resting state fMRI to assess functional networks, 18F-florbetapir-PET to measure Aβ, and a memory assessment. We characterized functional networks with graph metrics o ...[more]

PMID: 37626094

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Dataset Information

Functional network structure supports resilience to memory deficits in cognitively normal older adults with amyloid-β pathology.

Publications

Functional network structure supports resilience to memory deficits in cognitively normal older adults with amyloid-β pathology.

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