Just one more episode of that new favorite show on Netflix quickly turns into a 2AM bedtime with a 6AM wake up call. Not that you need another reason to make sure you get your sleep but the brain needs a nightly self-clean.
“Sleep puts the brain in another state where we clean out all the byproducts of activity during the daytime,” said study author and University of Rochester neurosurgeon Maiken Nedergaard. “Brain cells shrink when we sleep, allowing fluid to enter and flush out the brain,” Nedergaard said. “It’s like opening and closing a faucet.”
Without sleep, our brain can not get rid of the day’s toxins which can lead to mental fog and crankiness.
Based on this newfound purpose of sleep, scientists believe that the varying sleep needs across species might be related to brain size. Larger brains should have a relatively larger volume of space between cells, and may need less time to clean since they have more room for waste to accumulate throughout the day.
These findings could lead to better understanding the mechanisms of neurodegenerative diseases like Parkinson’s, which is associated with a backup of cell waste in the brain.