By Samir Suweis (Padova, Italy).

The critical brain hypothesis has emerged as an attractive framework to understand neuronal activity, but it is still widely debated. In this talk, I will first present data from a multi-electrodes array in the rat’s cortex and show that power-law neuronal avalanches satisfying the crackling-noise relation coexist with spatial correlations that display typical features of critical systems. In order to shed a light on the underlying mechanisms at the origin of these signatures of criticality, a simple brain model with a common stochastic modulation and pairwise linear interactions will be introduced. I then will show that in such models power- law avalanches that satisfy the crackling-noise relation emerge as a consequence of the extrinsic modulation, whereas scale-free correlations are solely determined by internal interactions. Moreover, this disentangling is fully captured by the mutual information in the system. Finally, I will show that analogous power-law avalanches are found in more realistic models of neural activity as well, suggesting that extrinsic modulation might be a broad mechanism for their generation.


Mariani, B., Nicoletti, G., Bisio, M. et al. Disentangling the critical signatures of neural activity. Sci Rep 12, 10770 (2022).

Mariani B, Nicoletti G, Bisio M, Maschietto M, Oboe R, Leparulo A, Suweis S, Vassanelli S. Neuronal Avalanches Across the Rat Somatosensory Barrel Cortex and the Effect of Single Whisker Stimulation. Front Syst Neurosci 15:709677 (2021). doi: 10.3389/fnsys.2021.709677.

P.S: We apologize for the video recording slightly trimmed at the beginning…

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