Neurovascular coupling and bilateral connectivity during NREM and REM sleep
Abstract
To understand how arousal state impacts cerebral hemodynamics and neurovascular coupling, we monitored neural activity, behavior, and hemodynamic signals in un-anesthetized, head-fixed mice. Mice frequently fell asleep during imaging, and these sleep events were interspersed with periods of wake. During both NREM and REM sleep, mice showed large increases in cerebral blood volume ([HbT]) and arteriole diameter relative to the awake state, two to five times larger than those evoked by sensory stimulation. During NREM, the amplitude of bilateral low-frequency oscillations in [HbT] increased markedly, and coherency between neural activity and hemodynamic signals was higher than the awake resting and REM states. Bilateral correlations in neural activity and [HbT] were highest during NREM, and lowest in the awake state. Hemodynamic signals in the cortex are strongly modulated by arousal state, and changes during sleep are substantially larger than sensory-evoked responses.
Data availability
Source data and code for generation of all figures can be found here:Code repository location: https://github.com/DrewLab/Turner_Gheres_Proctor_Drew_eLife2020Data repository location: https://doi.org/10.5061/dryad.6hdr7sqz5
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Neurovascular coupling and bilateral connectivity during NREM and REM sleepDryad Digital Repository, 10.5061/dryad.6hdr7sqz5.
Article and author information
Author details
Funding
National Institutes of Health (R01NS078168)
- Patrick J Drew
National Institutes of Health (R01NS079737)
- Patrick J Drew
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All procedures were performed in accordance with protocols approved by the Institutional Animal Care and Use Committee (IACUC) of Pennsylvania State University (protocol # 201042827).
Copyright
© 2020, Turner 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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