The structural-functional-connectivity coupling of the aging brain

Area of Science:

• Neuroscience
• Aging Research
• Cognitive Science

Background:

• Aging commonly impacts memory and executive functions.
• Small vessel disease (SVD) is prevalent in older adults.
• Neuropathologies explain <50% of age-related cognitive decline, suggesting other factors like cognitive reserve are crucial.

Purpose of the Study:

• To investigate the relationship between structural-functional connectivity coupling (SFC), aging, cognitive abilities, cognitive reserve, and SVD in healthy elders.
• To explore SFC as a biomarker for brain resilience against cognitive aging.

Main Methods:

• Utilized a cohort of 176 healthy elders from the Harvard Aging Brain Study.
• Assessed structural-functional connectivity coupling (SFC), a measure of anatomical connections predicting neural activity.
• Controlled for age, sex, and education, and analyzed SVD markers like white matter hyperintensities and microbleeds.

Main Results:

• Global SFC and specific intra- and inter-network SFC decreased with age.
• Global SFC correlated negatively with total cognitive scores.
• Cognitive reserve (education) interacted with SVD markers (white matter hyperintensities, cerebral microbleeds) to influence inter-network SFC.
• Enlarged perivascular spaces were linked to higher inter-network SFC.

Conclusions:

• Cognitive ability is associated with global brain coupling.
• Cognitive reserve influences inter-network brain coupling, with SVD markers playing a moderating role.
• SFC is a potential biomarker for understanding cognitive aging and resilience in healthy elders.