Research: Sleep as Deep Clean for the Brain

https://www.inc.com/jessica-stillman/new-study-sleep-is-literally-a-deep-clean-for-your-brain.html

“What she discovered was that during non-REM sleep, large, slow waves of cerebrospinal fluid were washing over the brain. The EEG readings helped show why. During non-REM sleep, neurons start to synchronize, turning on and off at the same time,” explains Wired’s Sara Harrison. “Because the neurons had all momentarily stopped firing, they didn’t need as much oxygen. That meant less blood would flow to the brain. But Lewis’s team also observed that cerebrospinal fluid would then rush in, filling in the space left behind.”

In short, completely non-scientific terms, sleep allows your brain to take a bath, washing off all the toxins that build up just as part of the day’s daily business.