Older adults benefit from more widespread brain network integration during working memory

Area of Science:

• Neuroimaging
• Cognitive Neuroscience
• Aging Research

Background:

• The aging brain recruits more cortical regions for demanding tasks.
• Mechanisms of age-related expansion in cortical networks remain unclear.

Purpose of the Study:

• Investigate how task demands influence age-related cortical network reorganization.
• Examine functional magnetic resonance imaging (fMRI) activity, network connectivity, and cognitive performance in younger and older adults during a working memory (WM) task.

Main Methods:

• Used fMRI to measure brain activity and network connectivity.
• Assessed working memory (WM) performance across four individualized difficulty levels.
• Defined network integration as the ratio of within- to between-network connectivity.

Main Results:

• Network integration decreased with increasing difficulty in younger adults but increased in older adults.
• Age-related increases in integration were linked to right hemisphere connectivity.
• Higher WM capacity in older adults correlated with greater network integration at high task difficulty.

Conclusions:

• Changes in network connectivity represent an adaptive compensation in aging.
• Older adults recruit more distributed cortical networks as task demands rise.
• Findings elucidate mechanisms of age-related network reorganization and compensatory strategies.