Interesting but is there any comparison with CSF while awake? Is there more CSF movement while sleeping?
This 2019 paper touches on CSF while awake -- CSF tends to be coupled with the respiration cycle. We know that you can also induce CSF flow by changing respiration [1].
Recent papers have shown that there can be coupling between the hemodynamic response and CSF while individuals are awake [2].
1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3895787/pdf/204... 2. https://journals.sagepub.com/doi/abs/10.1177/0271678X2210746...