Scale-free behavioral dynamics directly linked with scale-free cortical dynamics
Naturally occurring body movements and collective neural activity both exhibit complex dynamics, often with scale-free, fractal spatiotemporal structure. Scale-free dynamics of both brain and behavior are important because each is associated with functional benefits to the organism. Despite their similarities, scale-free brain activity and scale-free behavior have been studied separately, without a unified explanation. Here we show that scale-free dynamics of mouse behavior and neurons in visual cortex are strongly related. Surprisingly, the scale-free neural activity is limited to specific subsets of neurons, and these scale-free subsets exhibit stochastic winner-take-all competition with other neural subsets. This observation is inconsistent with prevailing theories of scale-free dynamics in neural systems, which stem from the criticality hypothesis. We develop a computational model which incorporates known cell-type-specific circuit structure, explaining our findings with a new type of critical dynamics. Our results establish neural underpinnings of scale-free behavior and clear behavioral relevance of scale-free neural activity.
The data analyzed here were first published in Stringer et al. (2019) and are publicly available on Figshare at Stringer, Carsen; Pachitariu, Marius; Reddy, Charu; Carandini, Matteo; Harris, Kenneth D. (2018): Recordings of ten thousand neurons in visual cortex during spontaneous behaviors. Janelia Research Campus. Dataset. https://doi.org/10.25378/janelia.6163622.v6. Analysis and simulation codes are publicly available on Figshare https://doi.org/10.6084/m9.figshare.21954389.v1
Code for computational model, power law fitting, power law range [Shew Lab]https://doi.org/10.6084/m9.figshare.21954389.v1.
Article and author information
National Institutes of Health (NIHR15NS116742)
- Woodrow L Shew
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All experimental procedures were conducted according to the UK Animals Scientific Procedures Act (1986). Experiments were performed at University College London under personal and project licenses released by the Home Office following appropriate ethics review.
- Gordon J Berman, Emory University, United States
- Preprint posted: May 13, 2021 (view preprint)
- Received: May 3, 2022
- Accepted: January 6, 2023
- Accepted Manuscript published: January 27, 2023 (version 1)
- Version of Record published: February 15, 2023 (version 2)
© 2023, Jones et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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