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bioRxiv · 10.1101/2025.11.12.688042

Slow waves generation and propagation in a model of brain lesions

Gaglioti, G.·Dalla Porta, L.·Colombo, M. A.·Russo, S.·Nieus, T. R.·Deco, G.·Corbetta, M.·Sarasso, S.·Sanchez-Vives, M. V.·Massimini, M.
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Abstract

Slow waves (SWs), the hallmark of non-rapid eye movement (NREM) sleep, reflect the periodic occurrence of transient silent periods in cortical neurons (Down states). During NREM, SWs and Down states physiologically disrupt large-scale network interactions. Since early EEG studies, SWs have also been observed in awake patients after brain injury. Emerging evidence indicates that these intrusions of sleep-like activity interfere with ongoing network activity and contribute to motor and cognitive deficits; yet, the mechanisms governing the generation and spread of post-lesional SWs remain unclear. Here, we extend a neural mass model of EEG to capture transitions between wake-like and sleep-like dynamics and embed it in connectome-based networks with virtual lesions. This model supports that local disfacilitation, topology-dependent propagation, and synchrony-dependent amplification throughout the connectome are sufficient to produce post-lesional SWs. These mechanisms reproduce the spatial gradients of post-lesional SWs seen in patients and identify actionable targets for neuromodulation and rehabilitation.

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Gaglioti, G., Dalla Porta, L., Colombo, M. A., Russo, S., Nieus, T. R., Deco, G., Corbetta, M., Sarasso, S., Sanchez-Vives, M. V., Massimini, M.. 2025-11-13. Slow waves generation and propagation in a model of brain lesions. https://doi.org/10.1101/2025.11.12.688042

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