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Surprising Science

How Little Sleep Is Enough?

For most of us, eight hours of sleep is excellent and six hours is no good, but what about if we split the difference? What is the threshold below which cognitive function begins to flag?

What’s the Most Recent Development?

David Dinges, head of the Sleep and Chronobiology Laboratory at the Hospital at University of Pennsylvania, has the distinction of depriving more people of sleep than perhaps anyone in the world. His recent study measured how sleep loss affects alertness in laboratory settings, i.e. no coffee, no bright lights, no office chit-chat. It revealed that loss of concentration and performance on complex tasks is an inevitable consequence of sleep loss. What’s worse, even though subjects’ performance tanked as the days went on, they reported they didn’t feel affected by the loss of Zs.

What’s the Big Idea?

Sleep may be an unsuspecting factor in our daily performance but in reality, it is one of the most important. The amount of sleep we get is the backdrop against which everything in our day happens. “Americans average 6.9 hours on weeknights, according to the National Sleep Foundation. Which means that, whether we like it or not, we are not thinking as clearly as we could be.” The consequences of mediocre minds are serious and those who are deprived of sleep typically say they don’t feel affected. We are poor judges of our own performance. 


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