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bioRxiv · 10.1101/2021.08.15.456381

Characteristic core voxels in normal individuals revealed by hyperbolic disc embedding and k-core percolation on resting state fMRI

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

Hyperbolic disc embedding and k-core percolation reveal the core structure of the functional connectivity on resting-state fMRI (rsfMRI). Inter-voxel relations were visualized on embedded hyperbolic discs, and their core composition was traced using k-core percolation. Using 180 normal adults rsfMRI data from the Human Connectome Project database, scale- free intervoxel connectivity represented by IC-voxels composition, while visualized on hyperbolic discs using [Formula] model, showed the expected change of the largest component decreasing its size on k-core percolation eventually yielding the core structures of individuals. This kmax-core voxels-ICs composition revealed such stereotypes of individuals as visual network dominant, default mode network dominant, and distributed patterns. Characteristic core structures of resting-state brain connectivity of normal subjects disclosed the distributed or asymmetric contribution of voxels to the kmax-core, which suggests the hierarchical dominance of certain IC subnetworks characteristic to subgroups of individuals at rest.

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Whi, W., Huh, Y., Ha, S., Lee, H., Kang, H., Lee, D. S.. 2021-08-15. Characteristic core voxels in normal individuals revealed by hyperbolic disc embedding and k-core percolation on resting state fMRI. https://doi.org/10.1101/2021.08.15.456381

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