Reconfiguration of functional brain networks and metabolic cost converge during task performance
- Medical University of Vienna, Austria
- QIMR Berghofer Medical Research Institute, Australia
Abstract
The ability to solve cognitive tasks depends upon adaptive changes in the organization of whole-brain functional networks. However, the link between task-induced network reconfigurations and their underlying energy demands is poorly understood. We address this by multimodal network analyses integrating functional and molecular neuroimaging acquired concurrently during a complex cognitive task. Task engagement elicited a marked increase in the association between glucose consumption and functional brain network reorganization. This convergence between metabolic and neural processes was specific to feedforward connections linking the visual and dorsal attention networks, in accordance with task requirements of visuo-spatial reasoning. Further increases in cognitive load above initial task engagement did not affect the relationship between metabolism and network reorganization but only modulated existing interactions. Our findings show how the upregulation of key computational mechanisms to support cognitive performance unveils the complex, interdependent changes in neural metabolism and neuro-vascular responses.
Data availability
We cannot publicly share raw data for reasons of data protection; processed data have been deposited to Dryad Digital Repository under the DOI 10.5061/dryad.zcrjdfn7p
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Data from: Reconfiguration of functional brain networks and metabolic cost converge during task performanceDryad Digital Repository, 10.5061/dryad.zcrjdfn7p.
Article and author information
Author details
Michael Breakspear
Funding
Austrian Science Fund (FWF KLI 610)
- Andreas Hahn
Austrian Academy of Sciences
- Lucas Rischka
Australian National Health Medical Research Council (1099082 and 1138711)
- Luca Cocchi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: After detailed explanation of the study protocol, all participants gave written informed consent. The study was approved by the Ethics Committee (ethics number: 1479/2015) of the Medical University of Vienna and procedures were carried out in accordance with the Declaration of Helsinki.
Copyright
© 2020, Hahn 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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Reconfiguration of functional brain networks and metabolic cost converge during task performance
eLife 9:e52443.
https://doi.org/10.7554/eLife.52443
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