Sleep. We all need it, and you probably feel as though you’re not getting enough of it. In our 24/7 technological society, we seem to be increasingly sleep deprived. The Centers for Disease Control and Prevention has even cited a chronic lack of sleep as a public health epidemic, with an estimated 50-70 million adults in the United States having some level of sleep disorder. Fewer among us report getting a good night’s sleep than ever before, and sleep impairment leads to difficulty in concentration and focusing on tasks such as driving and work during the day. But what is sleep? Why do we need it? Here are just a few intriguing facts about our current understanding of sleep.
5. There Are Differing Opinions on Why We Need Sleep
Is the need to sleep a simple recharging of the physiological batteries, or is it similar to a defrag of the mental hard drive? Or is it something more? Certainly, the inactivity theory of sleep has some evolutionary survival benefit: it’s simply more efficient to “power down” at night and conserve resources. Some animals, such as bears, take this to the extreme and hibernate through the long, cold winter. The restorative theory of sleep suggests that the body uses this period to repair and rejuvenate itself.
A newer mode of thought when it comes to sleep, however, is the theory of brain plasticity, which states that the brain uses sleep as a sort of time to take inventory and decide what to purge and what to commit to learning memory. Studies in sleep deprivation have shown that dreaming is necessary, and that subjects will start having waking dreams if they are deprived of sleep for a few days.
4. Some Animals Sleep Most of Their Lives, While Others Don’t Need as Much
The phenomenon of sleep is observed throughout the animal kingdom, although different animals require varying amounts of sleep and carry it out in curious ways. Bats and cats, for example, may sleep half their lives away — as anyone who has a house cat can attest. Eerily, a dolphin can put half its brain asleep at one time and still remain active, no doubt leading to the myth that dolphins do not need sleep. The same goes for the myth about sharks, which sleep with their eyes wide open. Many lower-order animals such as insects seem to be able to simply switch over to lower states of activity, and the ability to sleep probably evolved as a coping mechanism to get through times of stress or adversity.
3. Tech Devices May Contribute to Sleeplessness
If you’re like many people, your Kindle or iPad is the first thing you pick up in the morning and the last thing you look at before going to bed. But it turns out that your smartphone or tablet may be killing you … or at least preventing you from getting a good night’s sleep. A 2014 sleep study from the National Academy of Sciences suggests staring at light-emitting eReaders — and that smartphone we all glance at one more time before lights out is included — significantly upsets natural circadian timing. A survey of 1,508 adults cited in the study revealed that about 90 percent use some form of electronics within an hour of bedtime. The current thinking is that blue wavelengths of light promote alertness by inadvertently mimicking natural sunlight. But hey, there’s an “app for that,” or actually several apps out there, which note the local sunrise and sunset times via GPS location and adjust the tint and light levels of your device accordingly.
2. Conditions Such As Sleep Apnea Can be Fatal
This one is always surprising and is a bit scary, considering that sleep apnea is so pervasive; more than 18 million people in the U.S. are believed to suffer from this condition. It turns out that severe sleep disorders can occasionally be fatal. Sleep apnea is a condition whereby breathing becomes shallow, slows, or sometimes stops all together during sleep, sometimes hundreds of times in a night. One hallmark of the disorder is compulsive snoring. It’s usually diagnosed by monitoring the patient during sleep, and many people — especially folks who sleep alone — fail to realize that they even have it. Sufferers of sleep apnea may also experience a frightening temporary state known as sleep paralysis upon awaking as well. Justin Tennison (of The Deadliest Catch), the Grateful Dead’s Jerry Garcia and NFL great Reggie White all passed away due to complications related to sleep apnea.
Although less well known than sleep apnea, another condition can lead to bad health consequences. Those suffering from hypnophobia, or a fear of sleep, can suffer from chronic insomnia. This anxiety disorder has several causes. Some high achievers may feel a sense of guilt falling asleep, as they have left work unfinished. Other cases, however, result from frequent nightmares, including the fear of death during sleep. Prescription drugs and/or therapy to reduce anxiety are used to treat this condition.
1. No Magic Number Exists For the Amount of Sleep a Person Requires
This is the No. 1 question everyone has related to sleep science: how much sleep do I need? Eight hours a night is typically cited, though most of us have experience with getting by for extended periods with much less. College kids will frequently pull all-nighters before tests, and sleepless stretches measured in days are rites of passage for medical interns and special-forces personnel. Navy SEALS stay awake for the first four days and only sleep four hours total during the infamous “Hell Week.” Shift workers and people who work continuously varying schedules inevitably find themselves shortchanged on sleep.
The amount of sleep we require can vary throughout our lives as well. Teenagers, for example, need more sleep than adults. There have even been proposals to roll back start times for high schools to reflect this need, as any teacher can attest that the first period of the day finds struggling students in a semi-catatonic state.
And then there are famous examples of folks like Thomas Edison, who was highly productive and seemed to only take occasional catnaps most of his life. Twitter founder Jack Dorsey reports that he only sleeps 4 to 6 hours a night, and two U.S. presidents — Barrack Obama and Bill Clinton — function on less than six hours a night. On the other end of the spectrum are creative types such as F. Scott Fitzgerald or Ray Bradbury, who often didn’t get out of bed until mid-morning. There’s even been research suggesting that night owls, those who stay up late into the night, are smarter and more productive. Certainly, our own personal “sleep number” is an internal message that we need to obey.