The older adult brain is less modular, more integrated, and less efficient at rest: a systematic review of large-scale resting-state functional brain networks in aging

Hamish A. Deery, Robert Di Paolo, Chris Moran, Gary F. Egan, Sharna D. Jamadar

Research output: Contribution to journalReview ArticleResearchpeer-review

15 Citations (Scopus)

Abstract

The literature on large-scale resting-state functional brain networks across the adult lifespan was systematically reviewed. Studies published between 1986 and July 2021 were retrieved from PubMed. After reviewing 2938 records, 144 studies were included. Results on 11 network measures were summarized and assessed for certainty of the evidence using a modified GRADE method. The evidence provides high certainty that older adults display reduced within-network and increased between-network functional connectivity. Older adults also show lower segregation, modularity, efficiency and hub function, and decreased lateralization and a posterior to anterior shift at rest. Higher-order functional networks reliably showed age differences, whereas primary sensory and motor networks showed more variable results. The inflection point for network changes is often the third or fourth decade of life. Age effects were found with moderate certainty for within- and between-network altered patterns and speed of dynamic connectivity. Research on within-subject bold variability and connectivity using glucose uptake provides low certainty of age differences but warrants further study. Taken together, these age-related changes may contribute to the cognitive decline often seen in older adults.

Original languageEnglish
Article numbere14159
Number of pages39
JournalPsychophysiology
DOIs
Publication statusAccepted/In press - 2022

Keywords

  • aging
  • fMRI
  • functional connectivity
  • large-scale networks
  • lifespan
  • PET
  • PRISMA
  • resting-state networks
  • systematic review

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