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Updated: Sep 23, 2026

Multi-electrode Array Recordings of Neuronal Avalanches in Organotypic Cultures
Published on: August 1, 2011
Arousal tunes neuronal avalanches across a directed percolation critical point
Brandon R Munn1,2, Christopher Whyte2, Eli J Müller1,2
1The University of Sydney, School of Physics, Faculty of Science, Sydney, New South Wales, Australia.
Abstract:
Neuromodulatory levels in the brain change moment to moment, yet are typically ignored in studies of neural criticality, where empirical support remains varied. Here we show in a biophysical network of bursting neurons that arousal acts as a mechanistic control parameter for a directed percolation phase transition. At intermediate arousal, neuronal activity exhibits peaked susceptibility, power-law avalanche size and duration distributions, universal shape collapse, and anomalous diffusion, jointly satisfying the hyperscaling relation of the 2+1-dimensional directed percolation universality class. Reanalyzing extracellular recordings in awake mice, we find that time-resolved susceptibility tracks pupil-inferred arousal as the model predicts. These results identify arousal as a physiological control parameter for neural criticality, offering a statistical-physics basis for the Yerkes-Dodson effect, and imply that arousal should be tracked at fine temporal resolution to obtain reliable empirical estimates of neural criticality.
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