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

作者：Park Ji Eun; Jung Seung Chai^*; Ryu Kyeoung Hwa; Oh Joo Young; Kim Ho Sung; Choi Choong Gon; Kim Sang Joon; Shim Woo Hyun

来源：Neuroradiology, 2017, 59(8): 781-789.

DOI：10.1007/s00234-017-1875-2

• Brain
• Resting-state functionalmagnetic resonance imaging
• Functional connectivity
• Dynamic
• Sliding window correlation

Purpose Brain connectivity is highly dynamic, but functional connectivity (FC) studies using resting-state functional magnetic resonance imaging (rs-fMRI) assume it to be static. This study assessed differences in dynamic FC between young healthy adults (YH) and elderly healthy adults (EH) compared to static FC.
Methods Using rs-fMRI data from 12 YH and 31 EH, FC was assessed in six functional regions (subcortical, auditory [AUD], sensorimotor [SM], visuospatial [VS], cognitive control [CC], and default mode network [DMN]). Static FC was calculated as Fisher's z-transformed correlation coefficient. The sliding time window correlation (window size 30 s, step size 3 s) was applied for dynamic FC, and the standard deviation across sliding windows was calculated. Differences in static and dynamic FC between EH and YH were calculated and compared by region.
Results EH showed decreased static FC in the subcortical, CC, and DMN regions (FDR corrected p = 0.0013; 74 regions), with no regions showing static FC higher than that in YH. EH showed increased dynamic FC in the subcortical, CC, and DMN regions, whereas decreased dynamic FC in CC and DMN regions (p < 0.01). However, the regions showing differences between EH and YH did not overlap between static and dynamic FC.
Conclusion Dynamic FC exhibited differences from static FC in EH and YH, mainly in regions involved in cognitive control and the DMN. Altered dynamic FC demonstrated both qualitatively and quantitatively distinct patterns of transient brain activity and needs to be studied as an imaging biomarker in the aging process.

• 出版日期2017-8