Blame it on the Industrial Revolution. That's when artificial light was invented, totally screwing up an innate sleep cycle that had us snoozing in a completely different way than we do today.
Before the electric light bulb, people slept in shifts. This "biphasic sleep" regimen was mentioned in literature as far back as The Canterbury Tales.
"If somebody came to a physician 200 to 300 years ago and said they slept all night, that would be abnormal," says Dr. Robert Israel, medical director of Unity Health System's Sleep Disorders Center in Greece and Brighton.
Everybody, he explains, "would go to sleep when it got dark out, sleep three to four hours, wake up spontaneously with energy to do chores, then sleep another three to four hours."
These days, the luxuries of contemporary life keep us awake when we used to be dreaming.
And some people believe we're sleep-deprived because of it. We stay awake until exhausted and try to cram our sleep into one full session — then we stress out if we happen to wake in the middle of the night, according to those ancient patterns.
But Thomas A. Wehr, a psychiatrist who served as a sleep researcher at the National Institute of Mental Health, says we shouldn't think of segmented sleep as a disorder but as a "natural pattern of human sleep that is reasserting itself in a modern world."
Sleeping in shifts is being studied by the NIMH as a potential breakthrough for people who wake up in the middle of the night and get so worked up about not falling back asleep that they can't.
It's not a question of suddenly converting sleeping patterns into two shifts. But it isabout helping people with troubled sleep feel less anxious about it.
Amy Campbell, a 44-year-old massage therapist from Rochester who has suffered with insomnia for 19 years, tried a short experiment with it. Typically, she has to take melatonin and over-the-counter sleep aids to get a solid eight hours of sleep; otherwise, she's lucky to get three hours.
Instead, when she woke in the middle of the night, she tried reading by candlelight and deep breathing to calm her mind. Within a few days, by not panicking at interrupted sleep, she actually slept more restfully.
Her journal entry from the fifth day, when she relaxed enough to sleep solidly, read: "What??????? For the first morning in weeks and weeks, I'm chipper. I listen to music in my car, and sing."
For a restful night, Israel suggests the standard "good sleep hygiene": no caffeine or stimulating activities before bedtime, and a dark bedroom with the temperature in the mid-60s.
"Alcohol puts you to sleep, but you wake up quickly afterward," he says.
But obsessing over getting the perfect eight-hour sleep is a good way to not get it. "Fewer hours of good sleep is better than multiple hours of interrupted sleep," says Dr. Donald Greenblatt, director of the Strong Sleep Disorders Clinic at the University of Rochester Medicine.
And if you decide to get up in the middle of the night, he advises thinking of it as a time to do something productive, such as writing letters or ironing clothes. Return to bed only when you start to feel sleepy again. "The important part," says Greenblatt, "is convincing your brain that you're doing this by choice."
And just think of all the stuff you'll be able to catch up on.
Sweet biphasic dreams.
Flanigan is a Rochester-based freelance writer.