Diffuse neural coupling mediates complex network dynamics through the formation of quasi-critical brain states

Nat Commun. 2020 Dec 10;11(1):6337. doi: 10.1038/s41467-020-19716-7.

Abstract

The biological mechanisms that allow the brain to balance flexibility and integration remain poorly understood. A potential solution may lie in a unique aspect of neurobiology, which is that numerous brain systems contain diffuse synaptic connectivity. Here, we demonstrate that increasing diffuse cortical coupling within a validated biophysical corticothalamic model traverses the system through a quasi-critical regime in which spatial heterogeneities in input noise support transient critical dynamics in distributed subregions. The presence of quasi-critical states coincides with known signatures of complex, adaptive brain network dynamics. Finally, we demonstrate the presence of similar dynamic signatures in empirical whole-brain human neuroimaging data. Together, our results establish that modulating the balance between local and diffuse synaptic coupling in a thalamocortical model subtends the emergence of quasi-critical brain states that act to flexibly transition the brain between unique modes of information processing.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Brain / physiology*
  • Humans
  • Magnetic Resonance Imaging
  • Models, Neurological*
  • Rest / physiology
  • Task Performance and Analysis
  • Time Factors