Abstract
Since the first measurements of neuronal avalanches, the critical brain hypothesis has gained traction. 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, ranging from highly synchronous states (with higher spiking variability) to desynchronized states (with lower spiking variability). Here, using both new and publicly available data, we test independent signatures of criticality and show that a phase transition occurs in an intermediate value of spiking variability, in both anesthetized and freely moving animals. The critical exponents point to a universality class different from mean-field directed percolation. Importantly, as the cortex hovers around this critical point, the avalanche exponents follow a linear relation that encompasses previous experimental results from different setups and is reproduced by a model.
- Received 6 November 2018
- Revised 18 February 2019
DOI:https://doi.org/10.1103/PhysRevLett.122.208101
© 2019 American Physical Society
Physics Subject Headings (PhySH)
Synopsis
New Evidence for Brain Criticality
Published 21 May 2019
Researchers observe a critical point—a feature indicative of a continuous phase transition—in the brain’s electrical activity as it switches from an asleep-like to an awake-like state.
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