Dreamland: Adventures in the Strange Science of Sleep
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For Ken Parks, life has gone on without any more incidents of sleepwalking leading to a courtroom. But it hasn’t been easy. He and Karen divorced not long after he was acquitted. Since then, he has largely stayed out of the public eye, and perhaps having had enough of his time in the media, he frustrated all of my attempts to find him in Toronto. He is still living there, however, and has five children, if the local newspaper is to be believed. In 2006, he ran for a seat on the local school board. It didn’t go over well. “Sleepwalking perhaps [could be forgiven], a medical thing, but not the embezzlement,” one local man said when telling a reporter why he wouldn’t vote for Parks.
Proving that there are some things in life that you can never live down, Ken came in last.
9
Game Time
Imagine, for a second, that you are in a casino in Las Vegas. You have been in town for a few days, spent too much and slept too little, and recently found out the hard way that you are not as good at poker as you had thought. Now would be a good time to find a wager where the odds, like a tipsy bartender, are tilted in your favor.
Here’s a hint: find your way to the sports betting parlor. This is the dark, cavernous room usually filled with men huddled over small monitors and wearing looks of such intense concentration that you would think they were directing the launch of the space shuttle or planning a land-based assault against a rogue dictator. What they are actually doing is getting drunk and hoping to make money while watching wealthy athletes play games.
That’s not to judge, of course. Betting on sports is popular because the games operate outside the realm of cruel probability. In blackjack, for instance, the dealer sliding you a 10 means that the odds that the next card will not be a 10 just went up. Yet in basketball, watching LeBron James dunk over an opposing center doesn’t impact what will happen the next time his team gets the ball, or even the final outcome of the game. LeBron could always twist his ankle three minutes later, miss the rest of his shots, or not get the ball passed to him again because he offended his teammates during a time-out.
What makes betting on sports possible is the point spread. This is the bookmaker’s attempt to impose order on the randomness of sports, and it is pretty much what it sounds like: given all of the known information about the game, it predicts that Team A is expected to beat Team B by a certain number of points. When you place a bet, you decide how you think that forecast is wrong. If you bet that Team A will score more points than predicted and you are right, you will make a little money; if you wager that Team B will pull off an upset and are right, you will make even more. If you’re in luck, the next Monday Night Football game listed on the board will be a matchup pitting a team from the West Coast against a team from the East Coast. For most gamblers, deciding which team to bet on comes down to factors such as hometown loyalty, the trend of the last few games, or which team is on the road. But there’s a much easier way to beat the odds: just put money on the team from the West Coast.
Betting tips wouldn’t seem to fit in a book about sleep. Yet sleep is the most obvious part of a cycle that affects almost all living things, from quarterbacks in the National Football League to bacteria in the locker-room shower. Living organisms have an innate sense of the length of a day, which isn’t all that surprising considering that, for the long history of life on earth, the sun has pretty much run the show. Plants rely on sunlight for energy, while animals have settled into niches based on the span of hours they considered the optimal time to be awake. As a result, somewhere inside the cells of most living things is what amounts to a fairly accurate twenty-four-hour clock, known as the circadian rhythm, which tells an organism when it is time to perform an important activity and when it is time to rest.
The first person to recognize this rhythm was an eighteenth-century French astronomer named Jean-Jacques d’Ortous de Mairan. Staring at his garden in 1729, he was struck by the fact that his plants extended their leaves in the daytime and then pulled them back at night. He assumed that it was based on sunlight, and he set up a simple experiment to test his theory. He took a bunch of plants down to his wine cellar, where there was no variation of light or temperature between day or night, and recorded the movements of their leaves. Sure enough, the plants continued to open in the morning and close in the evening, even though there was no daylight prodding them. De Mairan realized that the plants were anticipating sunlight rather than responding to it. They had an ingrained sense of when the day started, and they didn’t need light to clue them in.
The human body is more like de Mairan’s plants than you might expect. The circadian rhythm alters our body temperature and overall alertness level based on the time of day, a process that will make the body continue to stick to the sun’s schedule even if it is placed in the equivalent of a wine cellar overnight. Without any help from coffee, most of us tend to perk up around nine o’clock in the morning and stay that way until around two in the afternoon, which is when we start thinking about a nap. Around six in the evening, the body gets another shot of energy that keeps us going until about ten at night. After that, our body temperature starts to fall rapidly, and we get sleepy if we don’t turn to coffee or another form of caffeine. Evolutionary biologists don’t know exactly why the body operates on this sort of split rhythm, but the best guess is that the early-evening pick-me-up was advantageous to early humans who needed energy to make a fire or find their way back home after a long day of foraging for food.
All of which brings us back to betting on football games. In the middle of the 1990s, a few sleep researchers at Stanford University decided to test a theory. Studies had shown that strength, flexibility, and reaction times surge in the early evening when the circadian rhythm is pulling the body out of the post-lunch funk. Given that subtle effect on an athlete’s abilities, it stood to reason that a person at the peak of this alertness cycle would have an unseen advantage over someone whose internal clock thought it was time for bed. What the researchers needed to test their idea was a contest that not only pitted people of similar abilities at different stages of the circadian cycle against each other, but also a data set long enough to show reliable patterns.
They found it in the professional football games played on Monday night, some of the premier events in the NFL. Monday night games always start at 8:30 p.m. Eastern Standard Time, regardless of which teams are playing or which team has to travel. For the league, this guarantees the maximum number of viewers. Diehard football fans on the East Coast will stay up until past midnight if they have to, while sports fans on the West Coast can turn on the TV and watch the game while eating dinner after work.
The scheduling of Monday Night Football games presents a unique circadian problem, especially if a team from the West Coast is playing a team from the East Coast. Players on the West Coast team are playing at their equivalent of 5:30 p.m., no matter if the game is in Seattle or Miami. Players on the team from the East Coast, meanwhile, are three hours ahead in their own circadian cycles. In nature, this sort of mismatch couldn’t happen. It was only in the last sixty years or so that we’ve developed a way to travel so quickly across time zones that our internal clocks are no longer in sync with the daylight around us. Fitting its cause, we call this condition jet lag.
Without knowing it, athletes on teams from the East Coast are playing at a disadvantage. Because of the circadian rhythm, which they can’t control, their bodies are past their natural performance peaks before the first quarter ends. By the fourth quarter, the team from the East Coast will be competing close to its equivalent of midnight. Their bodies will be subtly preparing for sleep by taking steps such as lowering the body temperature, slowing the reaction time, and increasing the amount of melatonin in their bloodstream. Athletes on the team from the West Coast, meanwhile, are still competing in the prime time of their circadian cycle.
Every human body, ranging from a professional athlete to a suburban dad, will experience small declines in physical ability and mental agility the longer it f
ights against the circadian rhythm. In the modern NFL, this has a significant impact because teams in the league are more evenly matched than those in the other major sports, and anything that alters a single player’s ability has an outsized effect on the outcome of the game. What’s more, there is little that an East Coast team can do about the circadian disadvantage. The schedule gives coaches few chances to adapt to the time difference. Teams traveling on the road typically fly in the night before the game, and East Coast teams playing at home rarely attempt to put their body clocks on Pacific Standard Time. Coaches instead tell their players not to try to adjust to the time differences, preferring that they keep up with their normal sleep patterns for consistency.
The Stanford researchers dug through twenty-five years of Monday night NFL games and flagged every time a West Coast team played an East Coast team. Then, in an inspired move, they compared the final scores for each game with the point spread developed by bookmakers in Vegas. The results were stunning. The West Coast teams dominated their East Coast opponents no matter where they played. A West Coast team won 63 percent of the time, by an average of two touchdowns. The games were much closer when an East Coast team won, with an average margin of victory of only nine points. By picking the West Coast team every time, someone would have beaten the point spread 70 percent of the time. For gamblers in Las Vegas, the matchup was as good as found money.
In a test to ensure that their findings weren’t the result of West Coast teams simply being better during those years, the researchers expanded their scope and looked at every Monday Night Football game played during that twenty-five-year time span. They found that the overall winning percentages for West Coast and East Coast teams were essentially even when the teams were not playing a game against an opponent from the other coast. Nor were the results a reflection of home-field advantage. When an East Coast team traveled to another destination within its same time zone, it won 45 percent of the time. But if a team from the East Coast played somewhere in the Pacific time zone, its winning percentage shrunk to only 29 percent.
Later studies found that circadian patterns influenced the outcome of other sporting events as well. In the late 1990s, Leonard Kass watched the University of Maine women’s basketball team lose a game that they were favored to win in the National Collegiate Athletic Association tournament. The team had traveled to the West Coast for the game. “They just looked like they were out of phase,” he said.
Kass, a big fan of Maine women’s basketball, had more than a passing interest in the loss. A neuroscientist at the university who studies circadian rhythms, he decided to test how often a matchup of college teams on different circadian schedules resulted in an upset. He looked at several years of data from the men’s national basketball tournament and found that higher-ranked teams that had to travel across the country were at a distinct disadvantage. “The kiss of death is shifting three time zones,” he said. Teams that flew to the opposite coast were twice as likely to be beaten by a lower-ranked opponent in the tournament’s first round. Circadian schedules trumped natural ability.
The circadian advantage—or disadvantage, depending on your perspective– popped up in studies of figure skaters, rowers, golfers, baseball players, swimmers, and divers. Everywhere you turned, there was evidence of the body’s hidden rhythms at work. One study found that in sports as varied as running, weightlifting, and swimming, athletes competing when their bodies experienced the second boost of circadian energy were more likely to break a world record. Long jumpers, for instance, launched themselves nearly 4 percent farther when the body was at its circadian peak. But the circadian rhythm cut both ways. Athletes competing when their circadian rhythm corresponded to the so-called sleep gates—those times in the early afternoon or late nights when it’s easy for most people to fall asleep—consistently performed a little worse than normal, even if the slowdown wasn’t obvious to them.
Thanks to technology and medicine, every athlete at the college level and above is already close to his or her limit of sheer physical strength. In matchups at this elite stage, the tiniest advantage can mean the difference between winning and losing. In sports that require trials, such as gymnastics and figure skating, a disadvantage based on the time an early heat or qualifying round takes place can translate into a failure to get into the finals. Soon after these studies were published, athletic trainers became interested in the little-known effects of scheduling and sleep on physical performance. Here, they realized, was an unseen aspect of competition that could give them one of the few edges left in sports. Manipulating sleep and the circadian rhythm could be the last, untapped method of outflanking an opponent.
Charles Samuels is a plainspoken Canadian physician who seems more at home yelling in the stands at a hockey game than sitting behind a computer in a small office. Until 2005, his research focused on the health effects of working overnight shifts shown by police officers in Calgary, a city best described as the Canadian Dallas. That year, however, he started thinking about how the performance cycles that affected cops would influence the body of, say, a speed skater. “I’m interested in how sleep affects high-performing individuals,” he told me. “The sports thing started off as a hobby. I didn’t know that it was going to turn into something really quite demanding.”
It was fortunate timing. Canada around that time had decided that when it came to sports, it was tired of being the nation of nice. The 2010 Winter Olympics were set to take place in Vancouver in a few years, and the Canadian government made it a priority to win more medals than any other nation. It set up a $6 million fund called Own the Podium for research and development, spending money on things like studying the aerodynamics of bobsleds in wind tunnels. Samuels submitted an application to come up with ways to harness the circadian rhythm. He had a two-pronged approach. First, Samuels needed to find a way for an athlete to quickly overcome jet lag after traveling across multiple time zones. Then, he wanted to manipulate the circadian dips that would affect an athlete’s performance no matter when or where an event took place. The challenge was to master time and space in such a way that the body of, say, a Canadian sprinter competing in Beijing at 2:30 p.m. would think that it was really 6:00 p.m. and time for a boost of energy rather than a nap. Done correctly, mastering the body’s rhythms could provide a slight advantage over one’s rivals.
To do so, Samuels drew on research that went as far back as 1662, when French philosopher René Descartes correctly noted that the tiny pineal gland in the brain reacted to light hitting the eyes. He called this gland “the seat of the soul” because he believed that it was responsible for thought and the movements of the body. In the 1950s, researchers at Yale University discovered that one of the chief functions of the pineal gland is the production of a hormone called melatonin, which is released into the bloodstream at night. Like a parent singing nursery rhymes to a toddler, melatonin coaxes the body to fall asleep. High levels remain in the bloodstream into the morning. The discovery of this hormone helped scientists identify the gears behind the biological clock: a small cluster of cells deep behind the eyes called the suprachiasmatic nucleus (known as the SCN to biologists). These cells let the pineal gland know when the eyes pick up bright light. When it’s dark for a while, the pineal gland assumes it is bedtime and sends melatonin throughout the body to let the organs know that it is time to close up shop.
But here’s the thing: the pineal gland can be tricked pretty easily. For all of its wonders, the human body is still a reflection of a world where the only source of bright light was the sun. Abundant white light—especially white light with a slight blue tint that mimics the sky on a clear day—can fool the pineal gland into thinking that the sun is still up. That is why watching television or working on a laptop late at night can make it harder to fall asleep. The SCN registers the light from the TV and tells the pineal gland that it is a little bit of sunlight because that is all the brain is built to understand. With enough bright light over the right amount of time, the pine
al gland becomes something of a reverse snooze button, holding off on releasing melatonin because it thinks that it is still daytime.
Jet lag is debilitating because, light-wise, the body has no idea what is going on. You can feel this yourself the next time you travel across time zones. Let’s say that you are flying overnight from New York to Paris. When you land at eight o’clock in the morning Paris time, your body thinks that it is two o’clock in the morning, which it is back in the States. Walking out onto a Parisian street bathed in morning sunlight confuses the body even more. While the reasoning part of your brain grasps the concept of a time difference, your pineal gland only understands light. Because the human body wasn’t designed to hop across an ocean overnight, this gland reacts to sunlight coming at what it thinks is the middle of the night and considers it a sign of an abnormally long day. In effect, the body becomes convinced that it is still the afternoon of the day before and takes steps to rewind the circadian rhythm back an hour or two. Now you have a bigger problem: your body isn’t just six hours off of Paris time, it is eight hours off. And as anyone who has tried to fall asleep early for a few nights before a flight east across time zones knows, attempting to prepare the body for a time change is often an exercise in frustration. Many travelers simply can’t fall asleep at seven in the evening, no matter how exhausted they are during the day, because of the circadian rhythm’s early-evening shot of energy.
Samuels’s plan for the Canadian Olympic team came down to a hyper-awareness of light and its effects on sleep. He created a plan where athletes would begin to shift their exposure to light before they traveled, starting one day for each time zone that separated them from the place of competition. This would allow them to adjust to the time zone quickly once they got there and, just as important, to significantly improve their sleep the night immediately before an event. If this is done correctly, a Canadian athlete would have a natural edge. “The research into sleep has been done, but no one cares about it,” Samuels told me. “The U.S. cares even less. In the U.S. you’ll find it very difficult on a global scale to get coaches and trainers interested in sleep to the same degree that we are in Canada.”