Last year, my friends and I found that Harvard freshmen get an average of 6.5 hours of sleep per night, from a random self-reported survey sent out to the freshmen dorm lists that enlisted about 120 responders. Given that our authority figures have probably told us that we need 8 hours, it seems that we students are chronically sleep-deprived. Why do we sleep so little? Well, we’ll be more productive if we’re awake for longer…more social activities happen at night…everybody else sleeps for six hours a night, etc. But is the amount of sleep we have really optimal? Are we most productive with 6.5 hours of sleep? Can we do more with even less sleep? Or can we do more with more sleep?
In a 2003 study, researchers at the University of Pennsylvania School of Medicine found that those who slept 6 hr/night for 14 days showed decreases in behavioral alertness and working memory ability equivalent to those who stayed up all night. Those who have pulled an all-nighter probably agree that their productivity the next day is less than optimal. In addition, a study published in PNAS last year has shown that humans do not have the ability to reset their sleep homeostat to adjust to fewer hours of sleep, even when sleep deprivation is chronic.
You might be wondering, however, if power-napping several times a day could compensate for a few fewer hours of sleep. One form of polyphasic sleep deprivation is the Uberman sleep cycle. People who try this out sleep only 3 hours a day, in six 20-minute intervals spread throughout the day. If you want to remain a normal human with creative thoughts rather than a roboticized collection of flesh and bones, then you should probably avoid the Uberman, no matter how tempting 3 extra hours in the day may sound. For a more elaborate argument for why polyphasic sleep is not good for you, refer to Dr. Piotr Wozniak’s SuperMemo article.
On the other hand, it might be possible for us to do more with less time awake. Perhaps we can all be more productive with just a hundred extra minutes of sleep a day.