Despite the common belief, your brain doesn't actually shut down when you sleep. In fact, some parts of it are more active than when you're awake, including those portions of the brain that control memory and learning. Though research is ongoing, it's thought that the brain may consolidate memories during sleep. Other studies show that the area of the brain that's used when consciously remembering something, like a person's phone number, is active during sleep. Scientists have also determined that people can learn new but simple things in their sleep, like making an association between smells and sounds.
More about sleep:
- There are two main types of sleep that people cycle through each night: Rapid Eye Movement (REM) and Non-Rapid Eye Movement (NREM). The former is where dream happen, and the latter is where deep sleep happens. Most people have between 3 and 5 REM cycles a night, and missing out on either REM or NREM sleep can prevent a person from feeling rested.
- Older people generally spend less time in deep sleep than younger people do. This makes them feel less rested and means that they're more at-risk for sleep disorders, like insomnia.
- Babies' brains react to the sound of arguing or angry tones even when they're asleep, with the areas related to stress and emotion regulation being the most affected.