Aging, brain network connectivity, and cognition: evidence from resting-state dynamic arterial spin labeling

Background-suppressed dynamic arterial spin labeling (bDASL) has emerged as a robust method for measuring functional connectivity with substantially reduced systemic noise. We leveraged bDASL to characterize age-related changes in resting-state functional connectivity (rsFC) and to examine how these changes correlate with cognitive performance across the lifespan.

A total of 139 healthy adults underwent rsFC measurements using bDASL, among whom 115 also completed cognitive assessments. Group independent component analysis (ICA) was employed to identify four high-order resting-state networks: the default mode (DMN), dorsal attention (DAN), salience (SN), and frontoparietal control (FPN) networks. Seed-based analyses were then used to quantify intra- and inter-network rsFC. Multiple linear regressions were conducted to study these relationships.

Our findings demonstrate that aging was associated with widespread reductions in both intra-network connectivity within all four networks, and inter-network connectivity among the DMN-SN, DAN-SN, and FPN-SN. These connectivity differences were associated with diminished global signal fluctuations, suggesting that alterations in brain-wide dynamics accompany age-related changes in functional network organization. Crucially, the relationship between network connectivity and executive function differed by age, with preserved DAN-centered connectivity showing a strong association with executive function in older adults.

Although aging was associated with widespread reductions in functional connectivity, older adults who preserved greater intra-network DAN connectivity and stronger inter-network connectivity between the DAN and the DMN, SN, and FPN exhibited better executive function. These findings suggest that maintaining DAN-centered communication may contribute to cognitive resilience during healthy aging. Collectively, this work provides insight into patterns of functional reorganization associated with the aging brain and identifies DAN-centered integration as a potential marker of cognitive resilience.