Model-based whole-brain perturbational landscape of neurodegenerative diseases

Sanz Perl, Y.; Fittipaldi, S.; Gonzalez Campo, C.; Moguilner, S.; Cruzat, J.; Herzog, R.; Kringelbach, M. L.; Deco, G.; Prado, P.; Ibanez, A.; Tagliazucchi, E.

doi:10.1101/2022.09.26.509612

bioRxiv · 10.1101/2022.09.26.509612

Model-based whole-brain perturbational landscape of neurodegenerative diseases

Sanz Perl, Y.·Fittipaldi, S.·Gonzalez Campo, C.·Moguilner, S.·Cruzat, J.·Herzog, R.·Kringelbach, M. L.·Deco, G.·Prado, P.·Ibanez, A.·Tagliazucchi, E.

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Abstract

The treatment of neurodegenerative diseases is hindered by lack of interventions capable of steering multimodal whole-brain dynamics towards patterns indicative of preserved brain health. To address this problem, we combined deep learning with a model capable of reproducing whole-brain functional connectivity in patients diagnosed with Alzheimers disease (AD) and behavioral variant frontotemporal dementia (bvFTD). These models included disease-specific atrophy maps as priors to modulate local parameters, revealing increased stability of hippocampal and insular dynamics as signatures of brain atrophy in AD and bvFTD, respectively. Using variational autoencoders, we visualized different pathologies and their severity as the evolution of trajectories in a low-dimensional latent space. Finally, we perturbed the model to reveal key AD- and bvFTD-specific regions to induce transitions from pathological to healthy brain states. Overall, we obtained novel insights on disease progression and control by means of external stimulation, while identifying dynamical mechanisms that underlie functional alterations in neurodegeneration.

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Sanz Perl, Y., Fittipaldi, S., Gonzalez Campo, C., Moguilner, S., Cruzat, J., Herzog, R., Kringelbach, M. L., Deco, G., Prado, P., Ibanez, A., Tagliazucchi, E.. 2022-09-28. Model-based whole-brain perturbational landscape of neurodegenerative diseases. https://doi.org/10.1101/2022.09.26.509612

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