Differences in dynamic and static functional connectivity between young and elderly healthy adults.

Area of Science:

• Neuroscience
• Neuroimaging
• Aging Research

Background:

• Resting-state functional magnetic resonance imaging (rs-fMRI) traditionally assumes static brain connectivity.
• Brain connectivity is inherently dynamic, yet static analyses may miss crucial age-related alterations.

Purpose of the Study:

• To compare dynamic functional connectivity (FC) with static FC in elderly healthy adults (EH) versus young healthy adults (YH).
• To investigate age-related differences in brain connectivity patterns using both static and dynamic rs-fMRI approaches.

Main Methods:

• rs-fMRI data analyzed from 12 YH and 31 EH across six functional regions.
• Static FC calculated using Fisher's z-transformed correlation; dynamic FC assessed via sliding time window correlation.
• Differences in static and dynamic FC between EH and YH were computed and regionally compared.

Main Results:

• Elderly adults exhibited decreased static FC in subcortical, cognitive control (CC), and default mode network (DMN) regions.
• Dynamic FC showed both increases and decreases in EH compared to YH within CC and DMN regions.
• Regions with significant static FC differences did not overlap with those showing dynamic FC alterations.

Conclusions:

• Dynamic FC reveals distinct patterns of brain activity in aging, differing from static FC measures.
• Altered dynamic FC in cognitive and DMN regions highlights its potential as an imaging biomarker for brain aging.