A to Z's: Sleep Science Fundamentals
Welcome back to our Sleep Series, a string of blog posts about the role of sleep in our lives, including the benefits of achieving enough slumber and tips to help make it happen. As life grows increasingly stressful and complicated, it becomes more and more important to perform the necessary steps to take care of yourself, sleep being key among them.
Sleep: when you get the right amount of it, you feel energized and ready to take on your day. When you don’t get enough, you feel tired, groggy, and irritable. But how does sleep work, and why do we sleep? What makes sleep deprivation so worrying? Read on to find out.
During a night of shut-eye, your brain cycles between two basic states: slow-wave and REM. Slow-wave sleep tends to happen earlier in the night. It consists of slow pulses of electricity across a lot of brain cells. Rapid-eye movement (REM) sleep occurs later. It’s at the REM stage we have vivid dreams, and our brains show activity patterns similar to when we’re awake.
While scientists still aren’t in agreement about why we sleep, there are a variety of brain activities that take place during slumber. For instance, sleep plays a crucial role in encoding memory. During sleep, the brain replays experiences, thus strengthening your memories and consolidating what you’ve learned during the day. Sleep also helps you forget the less crucial memories of the day, essentially clearing the clutter from your head and making more room for the important stuff.
It’s possible that part of the reason babies and children sleep more is because they are learning an overwhelming amount of information and thus require more brain organization.
We also know that sleep helps the brain clean up in other ways. Mice studies have demonstrated that sleep is when the body washes out toxins that build up in the brain during waking hours. The space between cells widens while you sleep, allowing for the toxins to be rinsed away. It’s thought that this process may help protect you from neurodegenerative diseases like Alzheimer’s. (There is definitely a link between poor sleep and dementia, although whether one causes the other has yet to be proven.)
We know that without good sleep, reaction times are slower, pain tolerance is worse, and achieving proper focus is harder. In fact, driving while sleep-deprived is comparable to driving drunk, in terms of the number of accidents caused. The National Sleep Foundation reports that sixty percent of U.S. adults have driven while drowsy, and a disturbing one-third have fallen asleep behind the wheel.
Sleep isn’t just a way to feel alert and content. It’s a crucial time for learning and organizing. It’s also a matter of safety, and—if you drive regularly—even potentially a matter of life and death. Getting the proper amount of recommended sleep—between 7 and 9 hours for adults—might feel like a luxury, but it’s also a must.