The following are three of the major theories that have emerged.
This waste removal system, they suggest, is one of the major reasons why we sleep.
It’s important to realize, however, this study was done on mice and not humans.
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Earlier research had uncovered the glymphatic system, which carries waste materials out of the brain.
Support for this theory comes from the comparative research of different animal species.
Some 2012 research also suggests that sleep helps cement the things we have learned during the day intolong-term memory.
The Clean-Up Theory
Another major theory suggests that sleep allows the brain to clean itself up.
Brain cells produce waste products during their normal activities.
As we sleep, fluid flow through the brain increases.
This acts as something of a waste disposal system, cleansing out the brain of these waste products.
It is also possible that each of these theories can be used to explain why we sleep.
Sleeping impacts many physiological processes, so it is very possible that sleep occurs for many reasons and purposes.
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