Spinal fluid washing over the brain during sleep to remove waste

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Scientists Now Know How Sleep Cleans Toxins From the Brain
The synchronized brain waves of non-REM sleep may play a key role in preventing toxins from accumulating in a person’s brain.

One big contribution of the paper is it helps show that the systems Nedergaard has been studying in mice are present and hugely important for humans too. “It’s telling you sleep is not just to relax,” says Nedergaard. “Sleep is actually a very distinct function.” Neurons don’t all turn off at the same time when we’re awake. So brain blood levels don’t drop enough to allow substantial waves of cerebrospinal fluid to circulate around the brain and clear out all the metabolic byproducts that accumulate, like beta amyloid.

Sara Harrison