Disruption in structural-functional network repertoire and time-resolved subcortical fronto-temporoparietal connectivity in disorders of consciousness
Abstract
Understanding recovery of consciousness and elucidating its underlying mechanism is believed to be crucial in the field of basic neuroscience and medicine. Ideas such as the global neuronal workspace and the mesocircuit theory hypothesize that failure of recovery in conscious states coincide with loss of connectivity between subcortical and frontoparietal areas, a loss of the repertoire of functional networks states and metastable brain activation. We adopted a time-resolved functional connectivity framework to explore these ideas and assessed the repertoire of functional network states as a potential marker of consciousness and its potential ability to tell apart patients in the unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS). In addition, prediction of these functional network states by underlying hidden spatial patterns in the anatomical network, i.e. so-called eigenmodes, were supplemented as potential markers. By analysing time-resolved functional connectivity from functional MRI data, we demonstrated a reduction of metastability and functional network repertoire in UWS compared to MCS patients. This was expressed in terms of diminished dwell times and loss of nonstationarity in the default mode network and subcortical fronto-temporoparietal network in UWS compared to MCS patients. We further demonstrated that these findings co-occurred with a loss of dynamic interplay between structural eigenmodes and emerging time-resolved functional connectivity in UWS. These results are, amongst others, in support of the global neuronal workspace theory and the mesocircuit hypothesis, underpinning the role of time-resolved thalamo-cortical connections and metastability in the recovery of consciousness.
Data availability
Connectivity matrices will be made available open access through EBRAINS of the Human Brain Project.
Article and author information
Author details
Funding
Horizon 2020 Framework Programme (945539)
- Ane Lopez-Gonzalez
Horizon 2020 Framework Programme (785907)
- Gustavo Deco
Horizon 2020 Framework Programme (778234)
- Olivia Gosseries
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Muireann Irish, University of Sydney, Australia
Ethics
Human subjects: Written informed consent was obtained from all healthy subjects and the legalrepresentative for DOC patients.
Version history
- Preprint posted: December 12, 2021 (view preprint)
- Received: January 31, 2022
- Accepted: August 1, 2022
- Accepted Manuscript published: August 2, 2022 (version 1)
- Version of Record published: August 17, 2022 (version 2)
Copyright
© 2022, Panda 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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