Sleep is required for brain function. Specifically, it allows your neurons, or nerve cells, to reorganize.
During sleep, brain activity increases in areas that regulate emotion, thereby supporting healthy brain function and emotional stability.
While asleep you cycle through periods of non-rapid eye movement sleep (NREM) and rapid eye movement sleep (REM). It’s during REM sleep that we have the most vivid dreams.
When you sleep, your brain’s glymphatic (waste clearance) system clears out waste from the central nervous system. It removes toxic byproducts from your brain, which build up throughout the day. This allows your brain to work well when you wake up.
While you sleep, your body can make more white blood cells that can attack viruses and bacteria that can hinder the healing process. Your immune system relies on sleep to be able to fight harmful substances.
When you open your eyes in the morning, sunlight lets your brain know it is time to wake up. As day turns to night, your brain makes a chemical called melatonin (mel-a-TONE-in) that makes you sleepy.