BACKGROUND AND PURPOSE:

• Aging is associated with a loss in functional connectivity (FC) between brain regions important for
  • Higher-order cognitive processes (region: FPN)
  • Introspection and self-generated thoughts (region: DMN)
  • Sensory information integration (region: SAL)
• Won et al. (Journal of Alzheimer’s Disease Reports, 2023) investigated the effects of exercise on within- and between-network functional connectivity of the DMN, FPN, and SAL in older adults with intact cognition (CN) and older adults diagnosed with mild cognitive impairment (MCI)

METHODS:

• Prospective intervention trial
  • Older adults recruited from in-person informational sessions at retirement communities and community recreation centers
• Participants
  • 60 to 88 years
• Intervention
  • Before and after implementation of an exercise intervention
    • 12-week walking program
• Study design
  • A resting state functional magnetic resonance imaging (fMRI) was performed after the 12-week exercise program
  • Changes in network connectivity and cognitive function after exercise were assessed using linear regression
• Primary outcomes
  • Measures of cognitive function
    • Controlled Oral Word Association Test (COWAT)
    • Rey Auditory Verbal Learning Test (RAVLT)
    • Narrative memory test (logical memory; LM)
  • Changes in within and between network connectivity

RESULTS:

• Intact cognition: 17 | Mild cognitive impairment: 16
• 78.0 (SD, 7.0) years
• The 12-week walking program led to a significant improvement in cardiorespiratory fitness among participants (P=0.005)
• Following exercise, all measures of cognitive function also increased
  • COWAT (P=0.041)
  • RAVLT (P=0.035)
  • LM (P=0.014)
• There were also significant increases in network connectivity following exercise
  • Within network connectivity
    • In the DMNW | SALW
  • Between network connectivity
    • Between the DMN-FPNB | DMN-SALB | FPN-SALB

CONCLUSION:

• Exercise training may improve cognition and memory performance by increasing between and within brain network connectivity in older adults both with normal cognition and with mild cognitive impairment
• The authors state

These findings suggest regular participation in simple aerobic exercise like moderate intensity walking may induce neuroplastic effects even in the face of Alzheimer’s disease-related neurodegenerative processes that have resulted in a diagnosis of MCI

Learn More – Primary Sources:

Large-Scale Network Connectivity and Cognitive Function Changes After Exercise Training in Older Adults with Intact Cognition and Mild Cognitive Impairment