It's a purposeful irony of life, I suppose, that we never get to see ourselves in that state. We can only pay witness to our waking reflection, which to one degree or another is always fretting or afraid. Maybe that's why young parents find it so beguiling to spy on their children when they're fast asleep.
— Amor Towles. Rules of Civility (2011). New York: Penguin Books, 2012.
Spending evenings in front of a glowing computer, TV, or cellphone screen can put you at risk of depression, Science News reports. Nighttime exposure to light from gadgets has already been shown to contribute to insomnia, cancer, obesity, and diabetes. Now, a new study shows that screen glow can cause mood-related changes in the brain. For weeks, researchers exposed hamsters to eight hours a night of dim light — like that from a TV screen — instead of their usual eight hours of pitch darkness. They found that the rodents became lethargic and ignored their favorite sugary treats, suggesting that they weren't deriving "pleasure out of activities they once enjoyed" — a major indication of depression in humans, says study author Tracy Bedrosian. The rodents' brains also showed the same kinds of changes in the hippocampus that are common in depressed people. "The good news," Bedrosian says, is that the damage disappeared and the rodents' behavior returned to normal after researchers took the night lights away, meaning that simply powering down earlier may "undo some of the harmful effects" that late-night gadget users face. Over the past 50 years, depression rates in the U.S. have increased dramatically as artificial lighting at night has become more common.
— "Screen-viewing blues," The Week, August 10, 2012, p. 19.
As historian Robert Ekirch writes, sleeping for one uninterrupted interval is simply a function of artificial light and the industrial revolution. Before electricity and factories, segmented sleep — sleeping in two intervals — was all the rage. Benjamin Franklin was a fan: Between “first sleep” and “second sleep” he would get naked, throw open the windows and take cold air baths. The French called the period between the two sleeps “dorveille,” while the English called it “the watch.” Both terms sound ancient and spooky in a cool way, which made me search for other people who embrace this period of sleeplessness. On Medium, Ron Geraci describes this state as “an odd, placid form of being awake — more aware but less alert…a ripe sentience that allowed clear but limited thought and wanted stillness.”
* * * ...a shout out to the true sleep rebels, our beloved night owls. While they don’t necessarily have “two sleeps,” they do find themselves hyper-focused in the middle of the night. A self-described night owl, Stefanie Morejon, writes on Medium that her behavior is perhaps evolutionary, essential for human survival. “Somebody,” she writes, “had to stay awake to keep the fires burning, to protect the community and keep the night creatures at bay.”
— Adeline Dimond, "It’s not (always) insomnia, it’s segmented sleep," Medium Newsletter, December 19, 2024