The Sleep Lost to History

Modern life and technology have changed the way we eat, live, travel, and work.  One radical fundamental shift that doesn't get a lot of attention is how we sleep.  Not only are most people in the U.S. sleeping on a clean, bug free synthetic matress and pillow in a dedicated room (with only one other person on average no less!), but historians suggest that the standard eight hours of sleep a night is a historical fiction.  References in diaries and other documents reference segmented sleep, or the first and second sleep.  People often slept for an initial four hours, then got up for an hour or two to ready, interpert their dreams, pray, or have sex, only to fall back into sleep for an additional four hours of rest.  Many modern insomnia cases may actually be people reverting to this natural cycle, which has also emerged in sleep stuidies as a natural pattern when people are deprived of artificial light for 14 hours a day. There is even research that our biological clocks work on a cycle slightly longer than 24 hours, perhaps as an evolutionary advantage.

There are some fascinating articles about how the introduction of artificial light changed the pattern of daily life both physically, but also socially. Street lighting came to Paris in 1667, and followed in Lille and Amsterdam within several years.  Coffee houses stayed open later.  Secret underground nighttime religious services by those being prosecuted for their beliefs also normalized the use of the night.  Suddenly, the night became a place with things for reputable people to do, and not just the bastion of burglers.

So next time you wake up in the middle of the night, realize you may just be reverting back to a historical, natural pattern. 200 years isn't long in evolutionary terms for our new sleeping habits.

*You can download a computer program Flux to minimize your exposure to blue light before bed.  It has the added benefit of letting you see the web through rose colored glasses.  Or you can just minimize your screen time for the several hours before bed.