What does sleep do for the brain?

A lack of sleep can do terrible things for your memory, which is why we all need to remember to get a good night’s sleep.

By Christian Jarrett

Asked by: Sarah Cooper, Manchester

Too much stimulation of your brain cells can lead to neurotoxicity, which is dangerous, and so one tentative theory holds that sleep is a chance for the brain to enter a detox mode in which overall levels of neural excitability are reduced.

Sleep also helps the brain to learn, although the precise physiological processes that underlie this benefit are still being worked out. This means that after you’ve spent time revising or learning a new skill, it’s very important that you get a good night’s sleep. Doing so will help your brain to consolidate the neural connections that underlie new memories.

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