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bioRxiv · 10.64898/2026.10.15.757554

Structural topology shapes regional roles in neuronal avalanche initiation and termination

Abstract

Whole-brain dynamics unfold as fast, discrete, transient events known as, neuronal avalanches, whose propagation is constrained by the connectome, that is, the large-scale scaffolding of structural connections wiring the brain. However, the role of the connectome in determining the topographies of the start and end of these transient cascades remains unclear. Leveraging resting-state Magnetoencephalography (MEG) recordings and diffusion magnetic resonance imaging (dMRI) tractography across 42 healthy individuals, we examined whether the structural architecture of white matter tracts dictates the spatial origins and the end of cortical avalanches. We found that the probability of triggering and finishing an avalanche is strongly related to the structural nodal strength, showing a positive correlation that is highly robust to non-parametric spatial permutation testing and bootstrapping. This structure-function coupling is highly stable and robust across different activation thresholds, demonstrating that the choice of avalanche extraction threshold does not drive or alter our main findings. Collectively, our results suggest that structural properties determine a region's propensity to initiate and terminate neuronal avalanches.

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De luca, M., Demuru, M., Troisi Lopez, E., Gallo, E., Cafaro, G., Duma, G. M., Depannemaecker, D., Casagrande, G., Quarantelli, M., Granata, C., Sorrentino, G., Sorrentino, P., Angiolelli, M.. 2026-10-16. Structural topology shapes regional roles in neuronal avalanche initiation and termination. https://doi.org/10.64898/2026.10.15.757554

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