Sleeping at the Switch
- Université de Montréal, Canada
Abstract
Sleep slow waves are studied for their role in brain plasticity, homeostatic regulation and their changes during aging. Here, we address the possibility that two types of slow waves co-exist in humans. Thirty young and 29 older adults underwent a night of polysomnographic recordings. Using the Transition frequency, slow waves with a slow transition (slow switchers) and with a fast transition (fast switchers) were discovered. Slow switchers had a high EEG connectivity along their depolarization transition while fast switchers had a lower connectivity dynamic and dissipated faster during the night. Aging was associated with lower temporal dissipation of sleep pressure in slow and fast switchers and lower EEG connectivity at the microscale of the oscillations, suggesting a decreased flexibility in the connectivity network of older individuals. Our findings show that two different types of slow waves with possible distinct underlying functions, coexist in the slow wave spectrum.
Data availability
All codes and transformed data used for all the analyses and most specifically to produce all of the figures of the paper can be freely accessible using this link : https://github.com/jmlina/Slow_Wave_Switchers. As requested, the full software licensing will be provided during the review process. We will follow the guidelines you have mentioned as soon as people in charge will be back. All the process will be done for the final version.This information and link was also added in a new section at the end of the paper under "Additional data files".Dataset can not be shared as participants did not give consent for data sharing.For the raw data, a request needs to be formulated to the ethic committee of the Hôpital de Sacré-Coeur de Montréal, as raw data of human participants cannot be made public under Québec's law.The data provided will be anonymized and some will be processed. Researchers who request access to the data will need to provide their research protocol and their IRB approval for this protocol. The documents will be studied by the owner of the database (Julie Carrier) who will then also submit to her institution's REB for authorization to share the data. Data requests should be addressed to:Julie Carrier (PI): julie.carrier.1@umontreal.caSonia Frenette (in cc) : sonia.frenette@umontreal.ca
Article and author information
Author details
Funding
Canadian Institutes of Health Research (Vanier scholarship)
- Maude Bouchard
Canadian Institutes of Health Research (190750)
- Julie Carrier
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: The protocol was approved by the ethics committee of the Hôpital du Sacré-Coeur de Montréal and performed in accordance with the relevant guidelines and regulations. Participants provided informed consent and received financial compensation for their participation. (CMER-RNQ 08-136 08-002).
Copyright
© 2021, Bouchard 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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Sleeping at the Switch
eLife 10:e64337.
https://doi.org/10.7554/eLife.64337
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