Pre-stimulus phase and amplitude regulation of phase-locked responses is maximized in the critical state
Understanding why identical stimuli give differing neuronal responses and percepts is a central challenge in research on attention and consciousness. Ongoing oscillations reflect functional states that bias processing of incoming signals through amplitude and phase. It is not known, however, whether the effect of phase or amplitude on stimulus processing depends on the long-term global dynamics of the networks generating the oscillations. Here, we show, using a computational model, that the ability of networks to regulate stimulus response based on pre-stimulus activity requires near-critical dynamics—a dynamical state that emerges from networks with balanced excitation and inhibition, and that is characterized by scale-free fluctuations. We also find that networks exhibiting critical oscillations produce differing responses to the largest range of stimulus intensities. Thus, the brain may bring its dynamics close to the critical state whenever such network versatility is required.
Source code required to run all simulations, as well as datasets and scripts required to generate all figures presented here, are available on figshare.
Article and author information
Netherlands Organization for Scientific Research (612.001.123)
- Richard Hardstone
- Klaus Linkenkaer-Hansen
Netherlands Organization for Scientific Research (406.15.256)
- Arthur-Ervin Avramiea
- Klaus Linkenkaer-Hansen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Floris P de Lange, Radboud University, Netherlands
- Received: October 24, 2019
- Accepted: April 20, 2020
- Accepted Manuscript published: April 23, 2020 (version 1)
- Accepted Manuscript updated: April 27, 2020 (version 2)
- Version of Record published: May 12, 2020 (version 3)
© 2020, Avramiea 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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