Entropy production of Multivariate Ornstein-Uhlenbeck processes correlates with consciousness levels in the human brain

TL;DR

This study links entropy production in brain activity, modeled by multivariate Ornstein-Uhlenbeck processes, to consciousness levels, providing a physics-based metric to distinguish wakefulness from sleep.

Contribution

It introduces a novel application of stochastic thermodynamics to empirical brain data, demonstrating entropy production as a marker for consciousness levels.

Findings

Entropy production increases with consciousness level.

Monotonous relationship between entropy production and wakefulness to sleep transition.

Provides a physics-based signature of consciousness.

Abstract

Consciousness is supported by complex patterns of brain activity which are indicative of irreversible non-equilibrium dynamics. While the framework of stochastic thermodynamics has facilitated the understanding of physical systems of this kind, its application to infer the level of consciousness from empirical data remains elusive. We faced this challenge by calculating entropy production in a multivariate Ornstein-Uhlenbeck process fitted to fMRI brain activity recordings. To test this approach, we focused on the transition from wakefulness to deep sleep, revealing a monotonous relationship between entropy production and the level of consciousness. Our results constitute robust signatures of consciousness while also advancing our understanding of the link between consciousness and complexity from the fundamental perspective of statistical physics.