On a day off, taking a nap is a small but heavenly pleasure. Dozing at your desk isn’t—especially if a colleague walks in on you—but sometimes exhaustion just takes over. The 2008 Sleep in America poll, conducted by the National Sleep Foundation, found that nearly one-third of adults who work at least 30 hours a week have fallen asleep or become extremely drowsy on the job—behavior that employers often frown upon. Should they lighten up? Perhaps. In a knowledge-based economy that depends on sharp minds, a few minutes of shut-eye could be good for business.
A report in the June 2009 Proceedings of the National Academy of Sciences showed that a nap with REM (or “dream”) sleep improves people’s ability to integrate unassociated information for creative problem solving, and study after study has shown that sleep boosts memory. If you memorize a list of words and then take a nap, you’ll remember more words than you would without sleeping first. Even micronaps of six minutes—not including the time it takes to fall asleep, which is about five minutes if you’re really tired—make a difference.
My colleagues and I have found evidence that important memory processing occurs as you’re falling asleep, during the hypnagogic phase. That’s when the brain appears to be “tagging” memories of unresolved problems for subsequent processing. We’ve also discovered that naps can help people separate the gist of new information from extraneous details, and that catching some REM sleep makes them better at finding connections between weakly related words—a good indication that napping gets the creative juices flowing.
When you’re in need of sleep, though, certain skills start to slide. Visual discrimination, which allows you to sort out what you see, can fade over the course of a day. (For more about negative effects of too little sleep, see “Sleep Deficit: The Performance Killer,” HBR, October 2006.) A 30-minute nap can stop the burnout, and 60 to 90 minutes that include some REM sleep will improve visual discrimination.
The evidence that sleep aids memory, learning, and mental acuity comes from real-world situations as well as from carefully crafted experiments. For instance, in a recent New Zealand study, air traffic controllers working the night shift scored much better on tests of alertness and performance if they took a planned nap of 40 minutes during the shift. Another example: A consultant (and retired Harvard Business School professor) I met on a flight “confessed” that the most productive way to sort his thoughts after he spent days talking with executives was to deliberately set himself up to fall asleep, pen and notepad within reach, and wait for a solution to pop into his head.
How does an organization implement a pro-napping policy? Some companies have nap rooms; others, like Google, offer nap pods that block out light and sound. Google says its pods are an extension of the company’s flexible schedule policy—people work in ways that best suit them. If all that sounds expensive, you can institutionalize napping without spending a dime. Simply announce that it’s OK to take quick naps because they make people more productive. Try it out in one division and see what happens. Given the millions of dollars spent on programs to increase productivity, this small, low-cost experiment is worth doing.
Robert Stickgold is an associate professor of psychiatry at Beth Israel Deaconess Medical Center in Boston and in the Division of Sleep Medicine at Harvard Medical School. This article was created in partnership with Harvard Health Publications.
Extracted from Harvard Business Review, October 2009.
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