Creative breakthroughs, unconscious excursions, and mental dress rehearsals: The author of a new book on sleep pulls back the covers on the weird and wondrous things that can happen when your head hits the pillow.
Before he began writing Dreamland, David K. Randall had never given sleep much thought. You go to bed, you dream—maybe snore a little—and when the alarm rings, you start your day. "Then one night, I woke up on the floor in my hallway clutching my knee," Randall says. He had sleepwalked smack into a wall.
To learn how to prevent future nocturnal collisions, Randall made an appointment with a neurologist, but the doctor couldn't offer much help. ("There's a lot that we know about sleep," he explained, "and there's a lot we don't know.") Unsatisfied with advice to "take it easy," Randall—a journalist by trade—set out to do some investigating of his own. As he dug deeper into the science of sleep, he found that the third of our lives we spend snoozing is as full as our waking days. Consider:
Let's start with dreams. Are they really a window into the subconscious? There's the Freudian idea that a dream tells you something deep about yourself. But most dreams are remarkably mundane. They tend to be about the things we do each day. And they tend to be negative, revealing our anxieties. Some scientists think dreams are like mental dress rehearsals. If our brains practice handling situations at night, maybe we can deal a little better by day.
What's going on in the brain when someone sleepwalks?
The parts of the brain that control movement are awake while the parts responsible for consciousness are still asleep. It's a gray area between wakefulness and sleep, and it's kind of scary. Parasomnias—the medical term for out-of-the-ordinary behaviors during sleep—can be triggered by sleep deprivation. As the brain struggles to get the rest it needs, its delicately timed sleep cycles are disrupted, and strange things may happen. Sleepwalkers can do an amazing range of activities, from driving to having sex—a phenomenon known as "sexsomnia." In a famous case in Canada, a man committed murder in his sleep.
I can see why some couples prefer separate beds—or even bedrooms.
It's not a bad idea. One of nature's cruel jokes is that men snore more while their female mates tend to be lighter sleepers. Intriguingly, a woman's sleep quality may predict marital happiness. In preliminary research from the University of Pittsburgh, couples wore sleep monitors and rated their interactions for ten days. The results were clear: Women gave more negative ratings after they had slept poorly, but the same association was not true for men. A well-regarded sleep researcher in Britain cited a study that found that when a couple share a bed, every time one person moves, there is about a 33 percent chance the other person will be disturbed. His recommendation: one bed for sex, two for sleep.
I've read that a quarter of Americans take sleep medication. Are these drugs effective in the long run?
There's surprising research that suggests they're not. Scientists say that cognitive-behavioral techniques—relaxing before bed, getting up at the same time every morning—are more effective long-term. One thing that the drugs do is interfere with the brain's ability to form memories. So you might take a pill but still toss and turn, and the next morning—because you have no memory of the last eight hours—think, "Well, I must've been asleep the whole time."
What does sleeplessness do to our health?
In one study at UCLA, researchers found that brain structures associated with memory were about 10 to 20 percent smaller in patients with sleep apnea, a condition in which breathing temporarily stops or becomes shallow during the night, potentially interfering with sleep. Another study found that elderly women with sleep apnea were nearly twice as likely to show signs of dementia. In a culture that says, I'll sleep when I'm dead, a lot of us push ourselves. But if you don't sleep, you may not be fully living.
Maybe we should bring back nap time....
That would do a lot for us. Naps, scientists are now discovering, help us learn and come up with creative solutions to problems. A study funded by NASA showed that napping for as little as 24 minutes can improve certain cognitive functions. Google offers napping pods for its employees.
Got any favorite tricks for conking out at night?
We know that a falling body temperature helps people go to sleep. I like to hit the gym in the late afternoon, then get in the sauna, so my body temperature spikes and gradually drops again. A hot shower can have the same effect. I've learned to treat sleep with the same respect that I do other aspects of my health. I can't eat chili cheese fries every day and expect to fit in my pants. And I can't go to bed at a different time every night and think I'll feel okay. I've learned that sleep is a big part of who I am—and I want to be the best version of myself.
Amanda Schupak is a health and science writer in New York City.