Mind & Body

Science Says 'Sleeping on It' Really Can Help You Solve a Problem

It's one of those things you say to a friend when you don't know how to help them with a tricky problem: "Just sleep on it." After all, when the answer isn't coming, a good night of shut-eye can tend to shake it loose. Most of the time, it works! But there hasn't ever been much good science to back up that advice — until now.

Overnight Inventions

John Steinbeck once wrote that "a problem difficult at night is resolved in the morning after the committee of sleep has worked on it." But it's not just creatives who have benefitted from sleep's inspiration — scientists have sworn by it, too. It's said that Dmitry Mendeleev finally conceived of a way to arrange the periodic table after sleeping at his desk. And legend has it that Thomas Edison's creative process involved taking midday naps and writing down exactly what he thought when he woke up.

Today, most researchers agree that sleep has something to add to the creative process. And yet, when we're up against a deadline, we often resist sleep, staying up late and "powering through" instead. A new study, however, shows that this is probably the wrong move. Instead, we should take after Edison, Mendeleev, and Steinbeck.

A New Kind of Sleep Sound

For a new study published in Psychological Science, Northwestern University psychology researchers gave puzzles to 57 people and paired each one with a different sound. The sound looped for two minutes while the participant tried to solve each puzzle, which just kept coming until they failed to solve six of them. After being quizzed on which sound matched with which puzzle, they were given a sleep-monitoring device and allowed to go home.

That night while the participants slept, the sleep-monitoring device analyzed their sleep stages. When they drifted into slow-wave sleep, the device played the sounds paired with some of the puzzles they couldn't solve. The goal? To activate their memories of those puzzles during sleep.

Sure enough, when they returned to the lab first thing in the morning, the participants were able to solve more of the puzzles. They solved 31.7 percent of the puzzles that went along with their sleep sounds — that is, the ones their sleeping brains were cued to think about — compared with 20.5 percent of the others. The puzzle sounds led to a 55 percent improvement, which suggests that the problems your brain returns to while you're sleeping really are easier to solve in the morning.

Harnessing the Power of Sleep

If people are better able to solve puzzles that are reactivated during sleep, what could this mean for other problems that need solving? "There was this idea that during sleep the brain is resting, but now we know there's a lot of important work being done," says Mark Beeman, a professor of psychology at Northwestern and study co-author, in an interview with Markham Heid for Elemental.

"This research adds to a growing literature suggesting that sleep can reorganize information to facilitate problem-solving," added Kristin Sanders, who was the study's corresponding author. "It also suggests that replay of the problem memory during sleep is critical for this reorganization."

That means that if you're struggling with a stubborn problem — whether it's a technical obstacle or a relationship issue — you may want to think about it or write it down right before you hit the sack. If you really can't figure something out, consider listening to some calming music or tell your smart speaker to play you some nature sounds. Listen to those sounds while you're working on your problem before bed. Then, before you tuck in for the night, play those same sounds again. Keep them playing while you sleep. When you wake up, write down your first thoughts. It's not a guarantee, but those sounds and some restful sleep really could help you solve your problem.

Get stories like this one in your inbox or your headphones: sign up for our daily email and subscribe to the Curiosity Daily podcast.

Learn more about how sleep can help you solve problems in "The Committee of Sleep: How Artists, Scientists, and Athletes Use Dreams for Creative Problem-Solving — and How You Can Too" by Dierdre Barrett, Ph.D.We handpick reading recommendations we think you may like. If you choose to make a purchase, Curiosity will get a share of the sale.

Written by Kelsey Donk November 15, 2019

Curiosity uses cookies to improve site performance, for analytics and for advertising. By continuing to use our site, you accept our use of cookies, our Privacy Policy and Terms of Use.