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bioRxiv · 10.1101/2023.12.15.571860

Markov Spatial Flows in BOLD fMRI: a Novel Lens on the BOLD Signal Reveals Attracting Patterns of Signal Intensity

Miller, R. L.·Vergara, V. M.·Erhardt, E. B.·Calhoun, V.
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Abstract

While the analysis of temporal signal fluctuations and cofluctuations has long been a fixture of blood oxygenation-level dependent (BOLD) functional magnetic resonance imaging (fMRI) research, the role and implications of spatial propagation within the 4D neurovascular BOLD signal has been almost entirely neglected. As part of a larger research program aimed at capturing and analyzing spatially propagative dynamics in BOLD fMRI, we report here a method that exposes large-scale functional attractors of spatial flows formulated as Markov processes defined at the voxel level. The brainwide stationary distributions of these voxel-level Markov processes represent patterns of signal accumulation toward which we find evidence that the brain exerts a probabilistic propagative undertow. These probabilistic propagative attractors are spatially structured and organized interpretably over functional regions. They also differ significantly between schizophrenia patients and controls.

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Miller, R. L., Vergara, V. M., Erhardt, E. B., Calhoun, V.. 2023-12-15. Markov Spatial Flows in BOLD fMRI: a Novel Lens on the BOLD Signal Reveals Attracting Patterns of Signal Intensity. https://doi.org/10.1101/2023.12.15.571860

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