Slow waves and cognitive output have been modulated in humans by phase-targeted auditory stimulation. However, to advance its technical development and further our understanding, implementation of the method in animal models is indispensable. Here, we report the successful employment of slow waves' phase-targeted closed-loop auditory stimulation (CLAS) in rats. To validate this new tool both conceptually and functionally, we tested the effects of up- and down‑phase CLAS on proportions and spectral characteristics of sleep, and on learning performance in the single-pellet reaching task, respectively. Without affecting 24-h sleep-wake behavior, CLAS specifically altered delta (slow waves) and sigma (sleep spindles) power persistently over chronic periods of stimulation. While up-phase CLAS does not elicit a significant change in behavioral performance, down-phase CLAS exerted a detrimental effect on overall engagement and success rate in the behavioral test. Overall CLAS-dependent spectral changes were positively correlated with learning performance. Altogether, our results provide proof-of-principle evidence that phase-targeted CLAS of slow waves in rodents is efficient, safe and stable over chronic experimental periods, enabling the use of this high‑specificity tool for basic and preclinical translational sleep research.
The .edf files containing EEG/EMG signal (BL and M-T1-4), the corresponding labels detailing vigilance states (4s resolution), the temporal flags of the auditory triggers, and the counts from the single-pellet reaching task are publicly available in Dryad (doi:10.5061/dryad.bvq83bk99). All figures accompanied by an Excel file containing the numerical data and statistical analyses are provided with this submission as well as in the Dryad repository.
Closed-loop auditory stimulation method to modulate sleep slow waves and motor learning performance in ratsDryad Digital Repository, doi:10.5061/dryad.bvq83bk99.
- Christian R Baumann
- Daniela Noain
- Daniela Noain
- Daniela Noain
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All procedures were approved by the veterinary office of the Canton Zurich under license ZH231/2015.
- Denise Cai, Icahn School of Medicine at Mount Sinai, United States
© 2021, Moreira 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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