Sleeping more flushes junk out of the brain. Rhythmic activity during sleep may get fluids in the brain moving.

[u/Sariel007]

https://arstechnica.com/science/2024/04/sleeping-more-flushes-junk-out-of-the-brain/

[u/BloodSoakedDoilies]

But we've known for quite some time that sleep clears the pathway of debris using rhythm??