Criticality in the brain: A synthesis of neurobiology, models and cognition

TL;DR

This paper reviews how critical phenomena, occurring at multiple scales, underpin neural activity and cognitive functions, offering a unifying framework that bridges neurobiology, models, and cognition.

Contribution

It synthesizes evidence for criticality in neural systems and discusses its potential to explain brain function and dysfunction across scales.

Findings

Neural systems exhibit signatures of criticality across multiple scales.

Criticality may underpin flexible cognitive processes and brain health.

Disruptions in criticality are linked to neurological disorders.

Abstract

Cognitive function requires the coordination of neural activity across many scales, from neurons and circuits to large-scale networks. As such, it is unlikely that an explanatory framework focused upon any single scale will yield a comprehensive theory of brain activity and cognitive function. Modelling and analysis methods for neuroscience should aim to accommodate multiscale phenomena. Emerging research now suggests that multi-scale processes in the brain arise from so-called critical phenomena that occur very broadly in the natural world. Criticality arises in complex systems perched between order and disorder, and is marked by fluctuations that do not have any privileged spatial or temporal scale. We review the core nature of criticality, the evidence supporting its role in neural systems and its explanatory potential in brain health and disease.