Researchers from Israel’s Bar-Ilan University have shown that individual neurons in the brain need sleep to give the chromosomal repair system a chance to clear out daily debris accumulated during wake time. At night, neuronal traffic is light and damage caused by activity or environment can be fixed.

https://www.timesofisrael.com/to-sleep-perchance-to-let-dna-be-repaired-study-finds-new-reason-for-slumber/

https://www.nature.com/articles/s41467-019-08806-w