Dreamland: Adventures in the Strange Science of Sleep

by David K. Randall

  A few nights before he planned to leave for Scotland, Nicklaus went to bed still puzzling over what had happened to his swing. That night, he dreamed that he was once again pounding the ball onto the fairway, regaining his form as the Golden Bear pictured in so many sports sections. When he woke up, he suddenly realized that he had held the club slightly differently in his dream, an adjustment that allowed him to keep his right arm steady throughout the swing. It was a tweak that would be barely perceptible to anyone else, but Nicklaus instantly recognized that this was the cause of his recent troubles. He got out of bed and went directly to the course. There, he gripped the club like he had in his dream. He shot a 68, and the next day he shot a 65. His old stroke was back. “Believe me, it’s a lot more fun this way,” he told a newspaper reporter. “All I had to do was change my grip a little.” He went on to finish second at the British Open after scoring one of the lowest rounds in the long history of the tournament.

  In his sleep, Nicklaus had figured out a problem that was costing him ten strokes a round, which, in the high-stakes world of professional golf, was the difference between walking home with a $100,000 check and barely making enough money to cover the airfare. His dreaming brain was able to do something that it couldn’t when Nicklaus was awake and studying his poor performances. Clearly, something happened that night that led Nicklaus to wake up with a solution to his swing problem. But what?

  For as long as we have been dreaming, the stories our minds create while we are asleep have been credited as a source of insight. As Nicklaus’s dream about his golf swing shows, the breakthroughs aren’t always emotional. When a person lies down to sleep at night, the brain undergoes a process that is crucial to learning, memory, and creativity in ways that scientists are only now beginning to understand. What dreaming does for our brains is most evident in stories like Nicklaus’s, in which the mind solves a problem or develops a new thought without any conscious effort.

  Scientists and others who investigate how the mind works have long attributed insights like these to flittering strokes of genius, a mysterious dance of cells and neurons which adds up to a thought that changes the game. Viewing creativity and problem solving as onetime events echoes the thinking of the Ancient Greeks, who believed that ideas came from the Muses and that you needed to work to win their favor. Even hardened scientists with no inclination to believe in mythology have been amazed at how the mind, while in a dream, sometimes suddenly reaches the perfect solution to a problem. In 1865, August Kekulé, a German chemist, was working on a model of the structure of benzene, an important industrial solvent whose chemical makeup had been confounding engineers and scientists at the time. Kekulé woke up from a dream with a vision of a snake eating its own tail. As he lay in bed, he realized that benzene’s chemical bonds would fit into the same hexagonal shape. The discovery was so important to German industry that Kekulé was awarded a title of nobility. Albert Szent-Györgyi, a Hungarian scientist who won a Noble Prize in 1937 for isolating vitamin C, credited his dreams for regularly revealing solutions to stumbling blocks. “My work is not finished when I leave my workbench in the afternoon,” he wrote. “I go on thinking about my problems all the time, and my brain must continue to think about them when I sleep because I wake up, sometimes in the middle of the night, with answers to questions that have been puzzling me.”

  Naturally, dreaming and its role in creative thought are more celebrated the farther you move away from the hard sciences. In perhaps the most famous instance of dreams leading to art, Samuel Taylor Coleridge awoke from an opium-induced dream in 1816 with three hundred lines of poetry in his head. He was in the middle of writing them down when he was interrupted by a visitor, who stayed for nearly an hour. When Coleridge returned to the poem, he could remember only fragments of what had appeared so vividly to him in his dream, which accounts for why the last stanzas of his masterpiece “Kubla Khan” seem disjointed. About 150 years later, Paul McCartney woke up in his girlfriend’s bedroom thinking of a melody. He went straight to a nearby piano and began playing the tune for the future hit “Yesterday.” “It was just all there,” McCartney later told a biographer. “A complete thing. I couldn’t believe it.” In the summer of 2003, Stephenie Meyer was a stay-at-home mother living in the Arizona suburbs. On the day she was supposed to take her children to their first swimming lessons, she woke up from a dream in which a girl was talking in a meadow with a beautiful vampire, who was trying to restrain himself from killing her and drinking her blood. She immediately wrote down the conversation from the dream as accurately as she could remember it. That dream became the basis for the Twilight series of books and movies, which have since earned Meyer more than $100 million.

  On the surface, it seems like these ideas came out of nowhere. But a tiny bit of excavation shows that each dream had clear connections to what was happening in that person’s daily life. Complex, creative thoughts that appear fully formed were little more than solutions to life’s problems. Kekulé had been searching for the structure of benzene for months. McCartney was part of one of the most productive songwriting duos in history and in the midst of creating a historic succession of hit records, but he was facing the fact that the next Beatles album needed another song to be complete. Meyer had been starting and stopping ideas for novels for years, trying to find characters that were real enough to hook readers.

  Dreaming looked to be the time when the mind continued to work in its laboratory, testing approaches and solutions to situations that were a part of its waking life. But how? And could the process of creativity really be tested and observed in a research lab?

  In the 1960s, leading psychologists turned their attention to how we develop innovative solutions to problems. To begin with, these researchers had to define what they meant by creativity. The working definition they came up with was “the forming of associative elements in new combinations which either meet specified requirements or are in some way useful,” a definition wide enough to include both the chemical structure of benzene and the tales of lovesick vampires. The next step after defining creativity was to see whether there was any replicable method for how the mind comes up with new ideas. Psychologists crafted a four-step model to chart how we typically react when faced with a new problem that has no easy or obvious solution. In the first step, we engage in an intense but unsuccessful session in which our minds grapple with the basic elements of the problem or issue. Then we tend to put it aside and focus on other things that require immediate attention. That leads to a dormant period in which the problem doesn’t take up any conscious thought or attention. Finally, the solution comes to us in a sudden flash of insight at a time when either we are not thinking about it or we are dreaming.

  The most important part of the puzzle is what happens in the brain between when we put a problem aside and when a solution flashes in front of us. Is it simply the passage of time that allows the brain to come up with the new idea, or is there something more at work? In the early 1980s, Francis Crick and Graeme Mitchison theorized that dreaming was a crucial element of learning and creativity, two closely related skills that can lead to advantages for survival, ranging from finding scarce food to creating a new product for a business. That sleep—especially REM sleep—could be a time when the mind solves a problem makes intuitive sense. REM sleep is when our most vivid dreams occur and a period in which the mind is as active as it is while awake. If we spend little time in REM sleep one night, our brain will compensate by prolonging that stage of sleep the next night. It doesn’t take a huge leap to assume that the brain considers this time important.

  According to Crick and Mitchison’s theory, the brain picks up countless bits of information throughout the day, from the structure of the face of a waiter at lunch to the color and pattern of a coworker’s tie. When we learn something new—whether it is declarative, such as the facts of what happened at work last Wednesday, or procedural, like how to drive a car—the information flows through a part of the brain called the hippoc
ampus. Storing all of this information into long-term memory not only is impractical but also could slow our brains down from finding something important when we need it. The brain picks and chooses what it keeps and what it tosses, so that information that isn’t essential is forgotten to make way for what is coming the next day. The process of cleaning up and organizing the mind’s filing cabinet could take place during REM sleep, which would account for the randomness of dreams. Touches of creative genius are simply exaggerated versions of what happens when our brains remove the clutter every night. With only important information left, the mind may then be free to make associations that it couldn’t see before.

  While this theory was intriguing, Crick and Mitchison didn’t do much to prove it. In the first part of the 2000s, a team of researchers at the University of Lübeck in northern Germany decided to put it to a test in a laboratory setting. The question they hoped to solve was whether sleep was the catalyst for a new idea, or whether the time the brain spent working through a problem accounted for insights. They assembled a group of volunteers and asked them to solve a number puzzle. Researchers explained to the subjects that, to reach the six-digit answer to the problem in front of them, they should follow two rules that required no math skills beyond basic subtraction. The first step was to look at the relationships between six pairs of numbers in a string of digits. If a subject saw something like two 4’s in a row, he or she was told to respond with the repeated number. But if the two numbers were different, then the correct response would be the difference between them.

  What the researchers didn’t tell the subjects in the study was that there was actually a much easier way to get to the answer. In each instance, the second three digits in the answer were the mirror images of the first. That meant that if the first part of the answer was 4-9-1, the second part would be 1-9-4. It was a subtle pattern that no subject recognized during the training session, even after completing a block of thirty trial runs.

  After everyone knew how to solve the puzzle the long way, the researchers broke them up into groups based on how many hours they would get to sleep. One group was allowed to sleep normally for eight hours. Another was kept up all night. The third group, subjects who were trained to solve the puzzle during a morning session, was asked to come back eight hours later without taking a nap in between. Through this setup, researchers ensured that each group stepped away from the problem for the same number of hours. If the groups more or less improved equally, it would suggest that solutions to problems come after the brain has a long enough time to reflect. But if the improvement rates between the groups were different, it would suggest that something happened during sleep and dreaming that made a difference in their ability to interact with new challenges.

  When the results came in, it was clear that sleep was key. Subjects who did not get to sleep before their second shot at the puzzle showed little improvement. Those who slept eight hours, meanwhile, solved the task 17 percent faster. But that wasn’t all. The subjects who figured out the hidden, easy solution to the puzzle completed each set approximately 70 percent faster than their peers because they had to solve only the first three digits in the six-digit answer. Only one out of every four subjects in the groups that did not get to sleep caught on to the pattern by the end of the study. But almost everyone who slept eventually discovered the quick solution. Sometime in the night, their minds were able to construct a novel approach to a problem they had faced while awake. Subjects who didn’t get to sleep continued to conceive of each puzzle literally, following the by-the-book instructions handed to them by the research team. Sleeping, meanwhile, allowed the brains to develop a cognitive flexibility that led them to consider the situation in a new way.

  It was as if sleep stretched the muscles of the brain, and it responded by bending its conception of facts and reality in a way that let it arrive at a new vision. While this study confirmed that sleep did in fact enhance problem solving, the question remained of whether dreaming played a role in the process. Were dreams just a part of sleep that occurred at the same time that the brain was consolidating its memories and honing its new skills, or did dreams help the brain reach its goal?

  Back across the Atlantic one researcher at Harvard University turned to video games in his investigation into how the brain tags new information that later reappears in dreams. Robert Stickgold, a professor of psychiatry who was then in his early sixties, became interested in dream studies because of an experience he had had while hiking with his family in Vermont. One night, as he started to drift off to sleep, he felt like he was still on the mountain. Even though he was comfortably in bed, he had the very real sensation that he was grabbing rocks and pulling himself up. When he woke up two hours later, the feeling was gone.

  A few days later, he mentioned to his colleagues that he had the strange sense that his mind was replaying its day just as he fell asleep. He then learned he wasn’t alone. His friends told him that they had had the same experience after completing intense, focused activities like whitewater rafting, or—this being a group of Harvard professors—studying organic chemistry all day. Stickgold wanted to conduct a study to see whether this was a common occurrence, but he was stuck trying to design an experiment that didn’t require his bussing subjects to Vermont and leading them up a mountain.

  That’s when a colleague suggested Tetris. One of the most popular video games in history, Tetris requires players to sort falling pieces of assorted shapes into straight lines while listening to the soundtrack of a Russian folk song. As anyone who has played the game knows, there is something about it that sticks with you when you are sleeping. Stickgold assembled a group of college students, taking care to include those who had never played the game before and those who had spent more than fifty hours on the game. As part of the study, Stickgold let the subjects fall asleep normally in rooms in his sleep lab. He woke them up not long after and asked what they were dreaming about. Approximately three out of every five replied that they saw falling Tetris pieces. The challenges that the brain had grappled with during the daytime replayed in the mind as the subject went to sleep, just like with Stickgold’s sensation of climbing over rocks after his day in Vermont.

  More reports of Tetris dreams came on the second night of the study. It seemed that once the mind realized that being asked to sort falling shapes wasn’t a fluke, it decided to devote extra time to figuring out a strategy. All of the subjects who were new to Tetris reported seeing game pieces in their dreams, while only half of the experts did. Intriguingly, Stickgold included in the study several subjects who regularly suffered from amnesia. Among this group, too, he received reports of dreams of falling shapes, even though the subjects could not consciously remember playing the game. Each person’s brain used sleep as a time to rehash what it experienced while awake. When subjects played the game a second time, their Tetris dreams appeared to help them improve more than simply time alone.

  Other studies showed the same thing. Researchers in Brazil, using the violent first-person shooter video game Doom instead of Tetris, recruited volunteers to play the game in which they blasted zombies and monsters with shotguns, knives, and chainsaws for at least an hour before they fell asleep. When they were woken up from REM sleep and asked what they were dreaming about, monsters and chainsaws topped the list. Just like with Tetris, subjects who spent more time dreaming about the game demonstrated a greater improvement in their skills the next time they played than those whose brains hadn’t relived its experiences during sleep.

  Across town from Harvard, at the Massachusetts Institute of Technology, a neuroscientist named Matthew Wilson found that new information a rat learned during the day was incorporated into its dreams as well. He implanted tiny electrodes into the brains of his test subjects. He then recorded each rat’s brain waves as the rat searched through a maze. Wilson focused on a cluster of neurons in the hippocampus that were responsible for storing memory, including memories indicating that a particular place contained food or was d
ifficult to maneuver around—a job that is very similar to what the hippocampus does in our own brains. While the rats slept, Wilson noticed that the pattern of their brain waves almost perfectly matched what he saw while the rats were awake and moving through the maze. The data were so similar that Wilson was able to tell exactly what part of the maze the rat was dreaming about. The animals were replaying what they went through during the day and committing it to memory.

  Just as Crick and Mitchison proposed, sleep appeared to be the time Wilson’s rats focused on new and important information. Stickgold decided to take this line of study further, using the next best thing to electrodes implanted in human heads: more video games. Thanks to the Tetris experiments, Stickgold convinced Harvard to buy an arcade game for him called Alpine Racer 2 and install it in his sleep lab. The game was part of a new line of machines that required players to move their whole bodies, rather than just their thumbs. To play the arcade game, someone steps onto two platforms, each of which represents a ski, and grasps two movable blue handles, which stand in for poles. Players must move their legs and arms simultaneously to dodge trees and slalom through gates in a rough approximation of tackling a black-diamond run in Colorado. The immersive experience was a clear parallel to hiking in Vermont or any other full-body activity that melds decision making with physical movement, a taxing cognitive process in which time and patience lead to skill.

  Stickgold designed a study that would test whether humans continue to dream about new information throughout the night. His goal was to determine how novel data interacts with what the mind already knows. Like in the Tetris experiment, Stickgold recruited volunteers, who then played the game for forty-five minutes and slept in his lab that night. But this time, he decided to wait until some subjects had completed one or two sleep cycles, the roughly ninety-minute loops that the brain goes through every night, before he would wake them up and ask what was going on in their dreams. As in the Tetris experiments, almost half of the subjects who were woken up early in the night had dreams that seemed out of the video game, dreams of skiing or hiking in the mountains. But as the night progressed, the dream reports became less straightforward. Subjects began to say they were dreaming of things like moving quickly through a forest as if on a conveyer belt.