If you live to be 90 years old you’ll sleep for about 32 years of your life. “What that 32 years is telling us is that sleep, at some level, is important, and yet for most of us, we don’t give sleep a second thought,” says Russell Foster, a circadian neuroscientist, in his popular TED talk titled, “Why Do We Sleep?”
Most of us know that we should get more sleep but before we learn how, it’s important to learn why. We sleep everyday, but what actually is sleep?
What is sleep?
There are two stages of sleep: The first half of sleep, or the deep sleep stage, the one that makes you feel groggy if awoken during it, and the later half of REM. The latter half is particularly crucial because it plays a key role in encoding procedural memories—skills such as walking, talking, or riding a bike, according to Vincent Walsh, a professor of human brain research and Royal Society industry research fellow at the Institute of Cognitive Neuroscience in London.
Earlier in the night, slow-wave deep sleep is important for consolidating explicit memories, such as facts, new vocabulary, and declarative memories, like daily events or information learned in class, according to Walsh. In contrast, REM sleep is essential for creative problem-solving and the development of motor skills.
