Decoding the brain state-dependent relationship between pupil dynamics and resting state fMRI signal fluctuation
- Max Planck Institute for Biological Cybernetics, Germany
- Massachusetts General Hospital and Harvard Medical School, United States
Abstract
Pupil dynamics serve as a physiological indicator of cognitive processes and arousal states of the brain across a diverse range of behavioral experiments. Pupil diameter changes reflect brain state fluctuations driven by neuromodulatory systems. Resting state fMRI (rs-fMRI) has been used to identify global patterns of neuronal correlation with pupil diameter changes, however, the linkage between distinct brain state-dependent activation patterns of neuromodulatory nuclei with pupil dynamics remains to be explored. Here, we identified four clusters of trials with unique activity patterns related to pupil diameter changes in anesthetized rat brains. Going beyond the typical rs-fMRI correlation analysis with pupil dynamics, we decomposed spatiotemporal patterns of rs-fMRI with principal components analysis (PCA) and characterized the cluster-specific pupil-fMRI relationships by optimizing the PCA component weighting via decoding methods. This work shows that pupil dynamics are tightly coupled with different neuromodulatory centers in different trials, presenting a novel PCA-based decoding method to study the brain state-dependent pupil-fMRI relationship.
Data availability
All fMRI datasets, as well as the synchronized pupil-size vectors, reported in this paper have been deposited in Zenodo at https://zenodo.org/record/4670277 (DOI: 10.5281/zenodo.4670277).Source data for all figures have been uploaded in the system.
Article and author information
Author details
Funding
Max-Planck-Gesellschaft (internal funding)
- Xin Yu
National Institutes of Health (RF1NS113278-01,R01MH111438-01,S10 MH124733-01)
- Xin Yu
Deutsche Forschungsgemeinschaft (YU215/2-1,Yu215/3-1)
- Xin Yu
Bundesministerium für Bildung und Forschung (01GQ1702)
- Filip Sobczak
- Xin Yu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experimental procedures were approved by the Animal Protection Committee of Tuebingen (Regierungsprasidium Tuebingen; protocol KY12-14) and performed following the guidelines. The rats were imaged under alpha-chloralose anesthesia.
Copyright
© 2021, Sobczak 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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Decoding the brain state-dependent relationship between pupil dynamics and resting state fMRI signal fluctuation
eLife 10:e68980.
https://doi.org/10.7554/eLife.68980
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