PSU Mon Feb 20, 2012 81Poor sleep is said to affect everything from productivity to anxiety (not to mention anxiety about productivity), and worse still, it’s believed to affect, oh, nearly everyone. But could this modern malady have a historical cure?

The BBC reports that historians and sleep scientists alike are increasingly convinced that all evidence points to a preindustrial pattern of bimodal or segmented sleep. That is, as historian Roger Ekirch reported in his 2005 book At Day’s Close: Night in Times Past,┬ábefore lights and blinking devices filled our days and nights, weary bodies would fall into a sleep pattern that included some sleep when it got dark, then a period of wakeful (but still restful–sometimes including chatting with bedfellows or sex) time sometime during the night, and one more deep sleep before dawn. By the end of the 1600s, the article says, most European cities were lit at night, and, ever since, our pattern has been dashed. Our cities never sleep, and it seems we don’t do a good job of it either.

Now, as countless doctors recommend a standard 8 hours of sleep each night (and gently chide those who admit to more or less than that number), a psychological study from the 1990s, performed by Thomas Wehr (now an emeritus scholar with the National Institute for Mental Health), is being coupled with historical research like Ekirch’s to revive the idea that humans are built for a much different sleep pattern than we generally follow today. In Wehr’s study, subjects were kept in the dark for 14 hours a day. It was a tough adjustment, no doubt, but soon they fell into an easy and uniform cycle that looked just like what Ekirch had found in heaps of historical references: sleep, quiet wakefulness, and sleep.