TESS VIGELAND, HOST:
It's the weekend, so maybe you are lucky enough to get eight straight hours of sleep last night - or not. And if not, you may feel like a slumber failure, because we are all supposed to get that solid eight or nine. And we assume that's what our bodies need and crave.
Well, in a recent essay in the digital magazine Aeon, Karen Emslie counters that this sleep schedule may not be natural at all. Emslie says that before electric light, the night was exotic, a dark mysterious time associated with crime and the supernatural.
KAREN EMSLIE: So people went to bed earlier and naturally woke up after a few hours of sleep and had a period of night waking of perhaps two to three hours, which they used for quite peaceful activities like reading and writing and praying or making love, as they were refreshed after their first sleep. Then they would go back to sleep and then wake up naturally in the morning.
VIGELAND: This sleeping pattern is called segmented sleep. Historical documents across cultures show plenty of references to a first and second sleep, divided by a period of being awake in the middle of the night. But the light bulb changed everything.
EMSLIE: Night wasn't so scary. It became fashionable to go out to socialize. And our days were basically extended, you know, from maybe 10 hours of light to 16 hours of light. And this middle of the night night-waking was squeezed out effectively.
VIGELAND: But lest you think that time was just wasted when people woke in the middle of the night, there are some very well-known, very productive people who used that period of night-waking to think and to write, both before the advent of electric lighting and after - people like Thomas Jefferson and Frank Lloyd Wright. And they may have been onto something.
EMSLIE: There's also hormonal changes that are happening that aren't necessarily connected to sleep per se, but they're connected to night. For example, there are higher levels of the hormone prolactin in the brain. And that's a lovely hormone. It's the one that's associated with, for example, dreamlike hallucinations. It does seem to lend itself to perhaps a more creative flowing state of mind at that time of night.
VIGELAND: Emslie's interest in the subject is not purely objective. She is a segmented sleeper. She says she loves that time in the middle of the night and uses it to write. Of course, parents of young children may find all of this a bit ludicrous given that their segmented sleep patterns aren't voluntary, and, shall we say, rarely result in higher levels of productivity. But Emslie hopes that maybe if segmented sleeping starts to become normalized, people will realize it does have benefits.
EMSLIE: I think the digital revolution may slowly start to help people who do have these sleep patterns, because there is more and more flexible working, remote working. You can manage your time yourself. So our sleeping patterns will change again because of another revolution several hundred years further on. The digital revolution may be the anti-dote.
VIGELAND: And with that, I need a nap. Transcript provided by NPR, Copyright NPR.