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bioRxiv · 10.1101/454934

Criticality between cortical states

Fontenele, A.·de Vasconcelos, N. A. P.·Feliciano, T.·Aguiar, L.·Soares-Cunha, C.·Coimbra, B.·Dalla Porta, L.·Ribeiro, S.·Rodrigues, A. J.·Sousa, N.·Carelli, P. V.·Copelli, M.
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Abstract

Since the first measurements of neuronal avalanches [1], the critical brain hypothesis has gained traction [2]. However, if the brain is critical, what is the phase transition? For several decades it has been known that the cerebral cortex operates in a diversity of regimes [3], ranging from highly synchronous states (e.g. slow wave sleep [4], with higher spiking variability) to desynchronized states (e.g. alert waking [5], with lower spiking variability). Here, using independent signatures of criticality, we show that a phase transition occurs in an intermediate value of spiking variability. The critical exponents point to a universality class different from mean-field directed percolation (MF-DP). Importantly, as the cortex hovers around this critical point [6], it follows a linear relation between the avalanche exponents that encompasses previous experimental results from different setups [7, 8] and is reproduced by a model.

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Fontenele, A., de Vasconcelos, N. A. P., Feliciano, T., Aguiar, L., Soares-Cunha, C., Coimbra, B., Dalla Porta, L., Ribeiro, S., Rodrigues, A. J., Sousa, N., Carelli, P. V., Copelli, M.. 2018-10-29. Criticality between cortical states. https://doi.org/10.1101/454934

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