9 Amazing Facts About Dreams

You Might Use Them to Help Solve a Problem

You’ve heard it before, and now it’s legit—sleep on your problems to solve them. The catch: dreaming is only an advantage when it comes to solutions that require a Eureka-like flash of insight (for instance: what word can form a compound word with canal, true and boat?), finds a recent study at the U.K.’s University of Lancaster. During REM (rapid eye movement) sleep—the eyeball-jerking stage when vivid dreams often occur—the frontal cortex processes new information like the riddle above. As new experiences integrate with preexisting knowledge, memory networks are stimulated—and, as a result form new, random and sometimes wacky connections between unrelated concepts. Later, we wake up, stretch, and—we can’t explain how—but the brilliant and now-perfectly-obvious answer just comes to us. One we couldn’t see when we were doggedly trying to get at...for instance, Love.

...Or Dream Up the Next Big Thing

The automatic sewing machine, the computer-controlled anti-aircraft gun, Otto Loewi’s Nobel-Prize-winning experiment on nerve impulses—all came as concrete plans in a dream, says Deirdre Barrett, a psychologist at Harvard University and author of The Committee of Sleep. So, how do you increase the chances of your own Nobel-worthy breakthrough? First, think of your problem right before you go to sleep, says Barrett. Conjure up an image of the problem you need to solve (your Mac’s frozen screen, your husband’s face). Then, whatever you do, don’t move when you wake up; even turning your head may displace the dream. If you've had nonsensical dreams, think about whether the imagery or events could be a metaphor for something that relates in any way to the problem you're stuck on, says Barrett. In her weeklong study, 50 percent of the volunteers had a dream about their problem and 25 percent actually dreamt up a solution.

Why, Yes! You Can Be in Fiji by Midnight Tonight

You can try to control the content and stickiness of your dreams—if you believe the many new smartphone apps that are available. A recent tool, Sigmund, developed by Harvard and MIT graduate students, whisperingly repeats words that you pick out of a database (beach, flying, mermaid, queen) during your REM cycle (based on predictable sleep-wake times). Another app, Dream:ON uses the phone’s motion-detecting accelerometer to gauge when you’re in REM (you’ll be stick-still), at which point it kicks in with the sounds of your pre-programmed dream—walking in the woods or frolicking at the shore (as examples). No one’s saying app-influenced dreams are exactly like the movie “Inception”—not yet, anyway.

Bigger Dreamers Have Tinier Waistlines

We see headlines for the “Dream Diet” after finding this gem: The more time you dream each night, the less hungry you are for fats and carbs. Volunteers in a study at St Luke’s Hospital ate prescribed meals for four days under various sleep conditions, fasted for a day, and then ate as much of any food they craved on days six and seven. When they slept for only four hours per night, their metabolism slowed down and they consumed more foods of the pasta-and-chocolate-pudding variety. One culprit is less energy-regulating stage-2 sleep than usual. Another is fewer cycles of REM. Dreaming is calorically demanding—and because REM cycles get longer and longer only after the six-hour mark, you burn off fewer calories (yet paradoxically crave more) when you wake up too soon. If we dream a lot about cake, we may not (as desperately) want to eat it too.

Your Night-Owl Habit Has a Downside

Ninety percent of us have had a nightmare in the past year. But night owls (especially female ones) are likelier to be among the 2-6% who have bad dreams weekly, finds a study at Yúzúncú Yil University in Turkey. Sleep patterns are one possible culprit: Staying up and waking up late throws off circadian rhythms. And while everyone’s level of cortisol rises in the morning, the stress hormone may invade night owls’ dreams more—because it coincides with the REM cycle they’re having right before they wake up.

The Upside of Nightmares (Part One)

Now the good news: Nightmares can be good for your mental health. Stressed-out, sheet-dampening dreams actually lead us to a healthier state of mind when we’re awake, finds psychologist Rosalind Cartwright at Rush University. When she studied people undergoing serious stress—a divorce—she found a surprising paradox: depressed people often had dreams that were pleasurable (also short and lacking in detail), while their better-adjusted-and-more resilient peers had those of the ruthless variety (importantly, the nightmares involved the ex). On a subconscious level, dreaming about conflicts helps to resolve inner turmoil at the times when we need to most. This is how we work through our emotions. 

The Upside of Nightmares (Part Two)

Bad dreams during pregnancy—you know, the usual ones about birthing traumas and losing, hurting and rejecting the baby—may actually result in a shorter labor, find researchers at the University of Messina in Italy. Eighty minutes—on average—that’s how much faster women with nightmares gave birth compared to those with pleasant dreams. (They also have a lower rate of postpartum depression.)

You've Heard of Jet Lag? Meet "Dream Lag"

You saw your ex on the street last Monday, so why is it that you’re dreaming about him now? A day’s events often come back to us in dreams that night—but, just as often, they show up a week later. It’s the “dream-lag effect”: During REM, the hippocampus takes five to seven days to transfer select memories to long-term storage in the neocortex, finds a study led by Mark Blagrove, director of the Sleep Lab at Swansea University. “Dream lag” is associated with more positive emotions about previous events—which scientists chalk up to the way we reprocess memories in our dreams. This means that if you spot your ex today, next week’s dream will put him in a softer, kinder light than tonight’s.