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Thomas Farragher

Sleep, the final frontier: This guy studies it. Here’s what he has to say

Dr. Charles Czeisler at a sleep lab in the Division of Sleep and Circadian Disorders at Brigham and Women’s Hospital.Jessica Rinaldi/Globe Staff

We sit in candlelight, our knees almost touching, and I stare into eyes deep and soulful and talk about my dreams.


Dreams about floating in the sky, skimming treetops and avoiding power lines as I drift like a colorful hot-air balloon toward a lazy river in the near distance.

Technicolor dreams of parties, and old friends, and of the days of my youth when a tankful of gas and car full of classmates held the promise — and in my slumber holds it again — of joyous adventure in my little hometown.

“That sounds wonderful,’’ my companion tells me.

He is Charles Czeisler. And as we sit in the simulated near-darkness in the sleep lab at Brigham and Women’s Hospital, I know that he means every word.


He is, after all, one of the world’s pre-eminent experts on that one-third of our lives when we are under the covers, sleeping, or fighting sleep, or emerging from it when the bell rings on those intrusive alarm clocks both mechanical and biological.

And he knows something that perhaps you’ve suspected, sitting next to that dozing plumber on the T, or poking your snoring co-worker at some interminable staff meeting.

“There’s an epidemic of sleep deficiency,’’ Dr. Czeisler, director of the Brigham’s sleep matters initiative, tells me in an all-white room so silent that the traffic outside on Francis Street may as well be in Malden. “I don’t think that’s overstating things.’’

Czeisler is not given to overstatement. The man is a scientist, a guy who has devoted his professional life to decoding that netherworld we encounter when the sun sets, the lights go out, and dreams take hold. Or – as is increasingly the case – don’t.

They say if you can build a better mousetrap, the world will beat a path to your door. Turns out the same is true if you hold the keys that unlock the mystery that is deep, restful, undisturbed sleep.


Secret Service agents have sought his counsel. So have NBA athletes. He helped install a special room for napping at Fenway Park so the Red Sox — those jet-setting sluggers who now sit atop the baseball world — can get important shut eye. He has a World Series ring to prove it.

“When we go into the workplace, we find that one out of three people screen positive for a sleep disorder,’’ he said. “And 80 to 85 percent are undiagnosed and untreated.’’

That’s a lot of people walking around like zombies out there.

The statistics are enough to keep you awake at night:

Sixty-nine percent of adults routinely do not get enough sleep. On average, adults need at least seven hours of slumber.

About one-third of American sleep fewer than six hours each night. That’s twice the rate of a half century ago.

Every month, 8 million people fall asleep behind the wheel of their cars and trucks.

A Rand Corporation study has estimated the cost of US sleep deficiency at more than $411 billion every year in lost productivity, greater absenteeism, and increased risk of injury.

None of that surprises Czeisler, the son of a physician, who, it seems, was destined for this line of work. He’s 65 and at 6-feet-4 inches cuts a commanding presence in his sleep lab at the Brigham, where he’s collecting blood and urine samples from study participants who have no idea what time of day it is or even what day of the week from their beds in a room that floats on a slab.


As we talk, that candlelight I spoke of becomes gradually natural as our eyes adapt.

“People can read and do other things,’’ he said. “It takes about an hour, an hour and a half to do that. One of the reasons that people have difficulty going to sleep at night is they have so much artificial light. They’re staring at their screens. It’s activating systems that tell the brain that it’s daytime.’’

Czeisler has traveled the world in search of data about how we sleep, why we sleep, how long we sleep and how well. Turns out work in this slumbering corner of science remains in its infancy.

And there are surprises everywhere. Like this one: “One of the things we discovered was that the circadian clock regulating sleep sends the strongest drive for wakefulness just before we go to bed at night and the strongest drive for sleep shortly before we get up in the morning.’’

Paradoxical? Yes. But it turns out evolution has something to do with it.

“You might imagine that you wouldn’t want people taking a nap when the sun goes down,’’ he said. “Then they wake up and they don’t know where they are. So built into us somehow during evolution there’s this tremendous waking drive that happens a couple hours before the sun normally sets. That probably had survival value. You could get back to the cave — or to some safe place — before dark.’’


In 2005, his research led him to a remote mountain village in southern Brazil. He wanted a place that had no electricity and he found it here. He also found a family of nine living on a dirt floor in a single room. The only light source was from a tomato can of kerosene that could be lit with a wick.

Czeisler asked the family’s matriarch a simple question: What happens when the kids get up in the middle of the night?

“She doesn’t understand the question,’’ he said. “I repeat it. I can’t understand why she can’t understand the question because it’s not that complicated: ‘What happens when the kids get up?’ Finally the translation goes back and forth three or four time and she says, ‘Oh! Nobody ever wakes up at night.’ ”

At this point, Czeisler lets loose loud laughter and slaps his thigh.

Turns out that sometimes science can be funny. And less complicated than we make it out to be.

And sometimes it can surprise you. Like when Czeisler and a fellow sleep researcher found that our internal clocks can be reset with only two or three doses of light exposure. He once exposed a 66-year-old woman with a chronic sleep disorder to four hours of bright light every day for a week. The result? Her internal clock had been reset by six hours.


“We have a reaction to light just like algae,’’ he said. “We found that we’re just as responsive to light as the cockroach. It was a blow to human exceptionalism.’’

Each year, we are now exposed to 10 times the amount of artificial light than we were just 50 years ago. And it’s going to get worse with LED lighting, which, he said, is going to expose us to a 10-fold again amount of light.

Because of their exposure to light, most Bostonians have shifted their internal clocks to a time zone somewhere between California and Hawaii.

The answer to this zombie-like existence is simple.

“You’ve got to have sufficient duration,’’ the sleep doctor told me. “People say, ‘I only have time for three hours of sleep.’ Well, that’s not going to cut it. The second thing is consistency of timing. A lot of people think, ‘OK, I’m going to set aside eight hours, but it’s going to be helter-skelter.’ A consistent schedule is really important. And the third thing is sleep quality. If you can’t breathe and sleep at the same time, then the first two are not going to be enough.’’

Czeisler’s expertise makes him quite a hit at cocktail parties and backyard barbecues. Sometimes, he identifies himself as a neuroscientist. Crickets.

But when people find out that he’s a sleep guru, they get in line.

They want their sleep problems diagnosed.

They want to tell him about their mid-summer’s night dreams, in which they fly, in which they are the nocturnal stars of colorful movies of their own making.

Thomas Farragher is a Globe columnist. He can reached at