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bioRxiv · 10.1101/2022.06.23.497413

Time-varying hierarchical core voxels disclosed by k-core percolation on dynamic inter-voxel connectivity resting-state fMRI

Lee, D. S.·Huh, Y.·Kang, Y. K.·Whi, W.·Lee, H.·Kang, H.
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Abstract

k-core percolation on the scale-free static brain connectivity revealed hierarchical structure of inter-voxel correlations, which was successfully visualized by hyperbolic disc embedding on resting-state fMRI. In static study, flagplots and brain rendered kmax-core display showed the changes of hierarchical structures of voxels belonging to functional independent components (IC). In this dynamic sliding-window study, temporal progress of hierarchical structure of voxels were investigated in individuals and in sessions of an individual. kmax-core and coreness k values characterizing time-varying core voxels were visualized on animated stacked-histogram/flagplots and animated brain-rendered images. Resting-state fMRI of Human Connectome Project and of Kirby weekly revealed the slow progress and multiple abrupt state transitions of the voxels of coreness k and at the uppermost hierarchy, representing their correlative time-varying mental states in individuals and in sessions. We suggest this characteristic core voxels-IC compositions on dynamic study fingerprint the time-varying resting states of human minds. One Sentence SummaryDynamic state transitions of hierarchical functional inter-voxel connectivity implied time-varying mental states at rest on fMRI

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Lee, D. S., Huh, Y., Kang, Y. K., Whi, W., Lee, H., Kang, H.. 2022-06-26. Time-varying hierarchical core voxels disclosed by k-core percolation on dynamic inter-voxel connectivity resting-state fMRI. https://doi.org/10.1101/2022.06.23.497413

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