Original Research ARTICLE
Cross-frequency interactions during information flow in complex brain networks are facilitated by scale-free properties
- 1University of Calgary, Canada
- 2University of Toronto, Canada
- 3McGill University, Canada
- 4Intelligent Systems Research Centre, Ulster University, United Kingdom
We studied the interactions between different temporal scales of the information flow in complex networks and found them to be stronger in scale-free (SF) than in Erdos-Renyi (ER) networks, especially for the case of phase-amplitude coupling (PAC)— the phenomenon where the phase of an oscillatory mode modulates the amplitude of another oscillation. We found that SF networks facilitate PAC between slow and fast frequency components of the information flow, whereas ER networks enable PAC between slow-frequency components. Nodes contributing the most to the generation of PAC in SF networks were non-hubs that connected with high probability to hubs. Additionally, brain networks from healthy controls (HC) and Alzheimer’s disease (AD) patients presented a weaker PAC between slow and fast frequencies than SF, but higher than ER. We found that PAC decreased in AD compared to HC and was more strongly correlated to the scores of two different cognitive tests than what the strength of functional connectivity was, suggesting a link between cognitive impairment and multi-scale information flow in the brain.
Keywords: Complex Network, brain network, scale-free network, Alzheimer's disease, random walk, information flow, cross-frequency coupling (CFC), Random network
Received: 18 Mar 2019;
Accepted: 08 Jul 2019.
Edited by:Chris G. Antonopoulos, University of Essex, United Kingdom
Reviewed by:Paul J. Laurienti, Wake Forest School of Medicine, United States
Paola Valsasina, San Raffaele Scientific Institute (IRCCS), Italy
Copyright: © 2019 Sotero, Sanchez-Rodriguez, Dousty, Iturria Medina and Sanchez Bornot. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Roberto C. Sotero, University of Calgary, Calgary, Alberta, Canada, firstname.lastname@example.org