Power of Napping

All I know is that I work from home, and most days (not all), I take between a 30-60 minute nap sometime after 2 pm, and if for whatever reason, I can't indulge, I become sluggish.

WSJ.com - Cubicle Culture:

No one exactly schedules a slumberous coma each afternoon, but for many people, it's more punctual than the coffee cart. No sooner do you get back from lunch than every document seems like an opiate, every colleague a sheep to count, and the creepy carpeting an enticing feather bed. It's the only time of day when the incessant chatter of a cube mate can fade like a lullaby. Even insomniacs can't always withstand the contagion of a yawn in the middle of the afternoon.


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The tussle to stay awake is clearly a sign that work is at odds with our nature. We're a society that has ritualized the sleep deprivation that caused such disasters as the Exxon Valdez and Chernobyl, so our daily battle is also evidence of just how dumb the planet's smartest beings have become.

"You're phenomenally stupid when you're sleep deprived, and you're too stupid to realize it," says Bob Stickgold, assistant professor of psychiatry at Harvard Medical School. "We are certainly the only known organism that sleep deprives itself."

Most mammals are designed to stay awake if there's rapidly changing emotional input, Prof. Stickgold says. But monkeys, for example, don't tend to put their social needs on a collision course with their sleep needs, the way humans do.

The main problem is that the mechanics of the human body don't mesh very well with a 9-to-5 work day. Researchers have found that when humans are fed at regular intervals and deprived of all sources of time, such as light and clocks, they have the greatest tendency to fall asleep during two periods of the day: between 1 a.m. and 4 a.m. and 1 p.m. and 4 p.m. These are natural dips in our biological clocks, or circadian rhythms, and the core body temperature drops along with a person's eyelids.

Potentially plunging us farther into oblivion is a metabolic tendency -- called the post-prandial dip -- to get tuckered out after a meal, though researchers disagree on how much of it is attributable to the meal....

"In the afternoon, all these physiological and mental processes begin to go into a dip," says Sara Mednick, a researcher at the Salk Institute. "This dip used to be thought of as a post-lunch dip. But it's been shown to occur when people eat or don't eat." In fact, from the moment you wake up in the morning, she says, "there's pressure driving you back to sleep."

There's also increasing evidence that in the Middle Ages people napped all the time, Ms. Mednick says. But the advent of timepieces, light bulbs and factories made naptime inconvenient for all but the crankiest toddlers. "We're allowing society and pressures of modern age to prescribe our sleep and thought schedules," she says.