Dream warriors

Two Boston scientists, one from the laboratory bench and one from the bedside, are tackling an age-old question: Why do we dream and what does it mean?

by Lisa Birk

A man dreams his mother is riding a tiny tricycle back and forth across a stage.

"Love me, love me, love me," she sings operatically.

To a psychoanalyst, the dream might spotlight two aspects of the mother, emotional neediness and a penchant for drama.

To a neurophysiologist, the dream indicates a decrease in norepinephrine and a decrease in serotonin, leading to an increase in acetylcholine, which produced random images in the man's mind. Just like every other dream.

How we think about our dreams has always reflected how we think about our place in the universe. In ancient Greece, dreams were messages from the gods. In biblical times, dreams were prophecies. In contemporary America, experts are at odds -- are dreams a meaningful system? or are they a random process, a kind of brain tic? -- and have been for almost five decades.

The split is drawn vividly here in Boston, where psychiatrists Ernest Hartmann and J. Allan Hobson, former colleagues at a Harvard teaching hospital, have been rivals in the field of dream theory for nearly 40 years. Now they are battling it out again, if indirectly, on the bookshelf. Hartmann, a psychoanalyst, Tufts med-school professor, and director of the sleep-disorders center at Newton-Wellesley Hospital, describes his approach in his 1998 book, Dreams and Nightmares: The New Theory on the Origin and Meaning of Dreams (Plenum). Allan Hobson, a Harvard med-school professor and director of Harvard's neurophysiology lab, describes his latest approach and its implications in his book Consciousness, published in November by W.H. Freeman.

Both men are challenging Freud's dream theory, which is to say they are challenging not only the notion of the unconscious, but also talk therapy, free will, the muse, the nature of creativity, and the nature of madness. They are challenging, in other words, our reigning image of ourselves. But they are challenging that image in very different ways, and no one is yet sure what will be erected in its place.

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The way we think about dreams today was shaped nearly 100 years ago by a neurologist named Sigmund Freud, who decided neurology was too primitive to say much of anything about dreaming. Freud invented modern psychiatry with his paradigm-breaking book The Interpretation of Dreams, which, among other things, proposed the idea of the conscious and the unconscious mind.

For nearly 50 years, psychiatry students were trained in Freud's theory of the id, ego, and superego. They were trained in Freud's theory of the unconscious, Freud's theory of free association, Freud's theory of therapy, and Freud's theory of dreaming. Dreams were central to this system; Freud himself had called dreams "the royal road to the unconscious," meaning that dreams were the best path to the otherwise hidden and unknowable recesses of the mind. During sleep, he believed, our rational mind (the ego) relaxes, allowing instincts (the id) to surface. However, if our forbidden wishes or drives became too explicit, we'd wake up. Thus, he hypothesized, dreams were coded: they occurred in symbols, and the psychoanalyst's job was to decode the dream, and so permit the dreamer insight into his true self.

Then, in 1953, came a seismic shock. Two researchers at the University of Chicago discovered that sleepers experienced bursts of rapid eye movement in their sleep. The scientists also noted that dreaming happened consistently and perhaps exclusively during these REM bursts, which suggested that the actual catalyst of dreams was not repressed memories or desires but, rather, a physiological process. Even animals, it seemed, had REM sleep.

Suddenly dreams, which according to Freud were an upwelling of powerful suppressed urges and anxieties, were being described as "automatic." Dream content might not be terribly important or even terribly individual -- because dreams were triggered not by one's horrible past, but by the release of a chemical.

If the scientists who discovered REM sleep were right, if dreams were merely a chemical process, then the unconscious was -- to put it bluntly -- a bunch of hooey. Talk therapy was a bunch of hooey. Among psychiatrists, the more scientifically inclined retreated to one shore and studied the brain. The psychoanalytically inclined retreated to the opposite shore and studied the mind. Scholarly articles took one side or the other. The world of psychoanalysis, which had tenuously bridged two worlds -- the medical and the psychological -- began to pull apart.

It was at this moment that Ernest Hartmann and J. Allan Hobson entered Harvard Medical School to finish their training as psychiatrists.

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The year Allan Hobson turned eight, he and his father built a lab for Allan's experiments. The family lived in West Hartford, Connecticut, near Avon Mountain, and Hobson frequently went foraging in the woods.

Sometimes he brought back snakes. Hobson was afraid of snakes, partly because he knew the woods were full of them (some of them poisonous), and partly because local wisdom had it that even if you bashed a snake's head in or chopped its head off, it wouldn't die until after sundown. Not only could snakes kill you; it seemed they also had supernatural powers.

Hobson investigated. His first set of experiments consisted of catching snakes and bashing their heads in. He'd take each snake back to the lab and wait for its body to stop wriggling. Sundown would come, and then his bedtime would come, and then sometime in the night the snake stopped twitching.

Hobson conducted a second set of experiments, which varied little from the first except that Hobson would wake himself periodically through the night to check on the snake to see exactly when it had stopped moving. He then conducted a third set of experiments, which again resembled the first except that Hobson began chopping the snake bodies into smaller and smaller bits. Still, each bit wriggled for hours.

Eventually Hobson figured out -- whether through further experiments or by reading books he no longer remembers -- that the snake's nervous system is segmented. The body twitches not because snakes are supernatural but because their physiology is set up that way.

By high school, Hobson was routinely dissecting brains, a hobby many of his classmates considered "weird, perverted and disgusting," he writes in the acknowledgments of his 1988 book, The Dreaming Brain. But adults, especially scientists, encouraged him. The first to do so was a dyslexia specialist named Page Sharp, who took an interest in the 15-year-old Hobson as a subject. Tests showed that Hobson had been born with dyslexic brain wiring but functioned normally. Sharp wanted to know why. Eventually, Sharp was so impressed with Hobson's intelligence that he hired him as a research assistant.

Some years later, Jack Ewalt, Harvard's charismatic chief of psychiatry at midcentury, must have seen something similar: an energetic, smart young scientist who was willing, even eager, to buck the trends. Ewalt partially funded Hobson's lab at Harvard's prestigious Massachusetts Mental Health Center when Hobson was still a lowly post-doc.

Hobson made good use of the funds and the lab. In 1973, 20 years after REM sleep was first linked with dreaming, he shook the psychoanalytic world with a lecture titled "The Brain as Dream Machine." No doubt the word "machine" was intended to rankle those who still believed that dreaming was a most human act -- that dreaming distinguished us from animals, and definitely distinguished us from machines.

Much of Hobson's research was based on cat brains, and many critics thought his presentation premature. Four years later, Hobson answered the critics with a flourish (some called it grandstanding): he opened "Dreamstage," a six-week "multi-media portrait of the sleeping brain" at Harvard's Carpenter Center. Crowds thronged in to see a human sleeper sleep, to see the machine that recorded the sleeper's brain waves. (The brain-wave patterns, it turned out, looked a lot like a cat's brain-wave patterns.) To some scholars, Hobson's exhibit bordered on the tacky. To the public, it was sexy and fun -- and who'd ever thought brain science could be fun? Hobson was a force to be reckoned with.

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But Hobson was not the only student singled out by Jack Ewalt in the early '60s. Ewalt also believed in another bright, promising young man, a Viennese named Ernest Hartmann.

Like Hobson, Hartmann was attracted to science. He remembers with distaste a psychiatry professor who urged students not to read books but just to "sit with the patients." Unlike Hobson, however, his approach to analysis was not shaped by chopping up snakes. It was shaped by, well, analysis.

Ernest Hartmann's father, the renowned Viennese psychoanalyst Heinz Hartmann, was an early and loyal disciple of Sigmund Freud. The junior Dr. Hartmann (at age two) even met Freud, a fact he includes on the jacket flap of his latest book.

Hartmann remembers a poll taken in the '50s or '60s, in which both psychoanalysts and the public were asked to name the best psychoanalyst in the country. The public voted for a doctor named Erik Erikson. The psychoanalysts, however, voted for Heinz Hartmann.

Hartmann senior was the psychoanalysts' psychoanalyst, and so loyal a Freudian that people nicknamed him the "son of Freud." So Ernie Hartmann is, he sometimes jokes, the grandson of Freud.

Meeting Hartmann is a bit like meeting Freud's grandson, or your mental image of Freud's grandson. He doesn't have the beard or the paunch, but his wispy hair sometimes stands up or out, the way really smart people's hair is supposed to. He has a Viennese accent, a courtly, almost old-fashioned kindliness, heavy red drapes, and a Newton home office lined floor-to-ceiling, wall-to-wall with books. In the middle of the office, he's placed two red leather chairs on either side of an elegant table stacked with thick books and a big rock incised with one word: DREAM.

Hartmann, however, is not such a loyal grandson when it comes to ideas. In decades of research, both as a scientist and as a psychoanalyst, he has come to reject nearly half of Freud's tenets. Hartmann does not believe, as Freud did, that dream content is irrational or even coded. He rejects the idea that all dreams are based on a repressed wish. What distinguishes Hartmann from most followers of Freud, according to J. Christian Gillin, a professor of psychiatry at the University of California at San Diego, is that Hartmann "is a more independent thinker." Hartmann has not just modernized Freud's theory, he has rebuilt it.

Hartmann goes along with neurophysiologists who say that dreaming is chemically activated; he's done some experiments along those lines himself. He just doesn't think that's very interesting. He wants to understand why we dream and what those dreams mean, and what the answers imply for a new model of the mind.

Hartmann spent years as a researcher and a psychoanalyst working with traumatized people, and over time he collected 40 dream series containing from six to a thousand dreams each. The dreams were collected in the weeks or months after a trauma or, in some cases, over five years.

The nightmares of traumatized people, he found, had certain common features: there was a strong feeling, often expressed in metaphor, and there were bits of the dreamer's past woven in.

Traumatized people often dreamed not so much about the facts of what had happened as about the way the event made them feel. This was particularly true as time went on. Sometimes people dreamed of the trauma itself -- say, a rape -- but the details, the setting, or the characters would be different. Later, people would dream about other traumas they hadn't experienced -- tidal waves, for instance -- but the dream rape and the dream tidal wave would engender a common feeling of terror.

Big losses triggered similarly metaphoric dreams. Hartmann writes of a man whose powerful mother had just died. In his dream, "This huge mountain has split apart and there are pieces lying around. I am supposed to make arrangements to take care of it." In the dream of a woman who had just lost her mother, "There was an empty house, empty and barren. All the doors and windows were open and the wind was blowing through."

These dreams, Hartmann theorized, were driven by emotion, but the content was metaphoric, and the metaphors were important. The metaphors, he writes, were a way of showing the dreamer, "It is a terrible event, yes, but is it unique? Let's look at . . . other catastrophes. . . . Awful, yes, but it's part of a whole catalog of human disasters, . . . [and] sometimes people survive." Dreams, in other words, are a way of healing the dreamer.

Many of the nightmares he studied drew on previous experience. Hartmann cites an example of a World War II vet who had a recurrent nightmare of a severed human head lying on the side of the road. He'd awaken horrified and angry. The dream puzzled the vet: for all the atrocities he'd witnessed, he couldn't recall having seen a severed human head. Then, after some therapy, he remembered an event from childhood that had conjured the same feelings. His pet guinea pig had disappeared, and some time later he found the guinea pig's head in the evening's stew. His mother was trying to supplement their poor diet.

Hartmann believes this sort of dream, the kind that draws on past experience, is an example of the brain saying, "Let's look at other times you felt terrified. Not quite the same? No, but let's keep looking; wasn't there some similar feeling? And you survived."

Dreams, in this conception, may be the mind's equivalent of fibroblasts. After a cut, fibroblasts knit together the edges of the skin. If trauma similarly rips the mind, then dreams, by making connections to other traumas and to past experience, help knit the psyche back together.

Hartmann collected another type of dream, too: those of scientists and artists. Among them is the story of inventor Elias Howe, who for five years had tried to invent a sewing machine. Howe could visualize most of the machine, a needle piercing fabric over and over, but he couldn't figure out how to get the machine to hold and knot the thread. Then one night he dreamed he was a missionary caught by natives carrying spears. The spears, he noticed, had holes in the tips. When he woke, he had the solution to his problem: a hole through the tip of the needle to hold and knot the thread.

Robert Louis Stevenson claimed to have dreamed the entire plot of The Strange Case of Dr. Jekyll and Mr. Hyde. More than 50 percent of mathematicians answering a survey said they had solved a problem in their dreams at least once. Hartmann lists famous artists, ranging from Albrecht Dürer to William Blake to Frida Kahlo, who recorded a dream as the source of their inspiration.

Hartmann began to think about the common properties of these two sorts of dreams: nightmares that made metaphors of trauma, and dreams that found solutions to problems. He began to think of dreaming as "hyperconnective," a state of mind in which we are able to make more associative leaps than we can in the waking state. And then, appropriately, he dreamed a visual representation of such a connective sort of brain. He dreamed of "a pile of Persian carpets loosely tied together."

As he developed the theory, Hartmann began to visualize the mind as composed of "neural nets" lying one on top of another. Imagine a pile of tiny electrified fishing nets. The spot where one rope knots with another is a neural connection. In the conscious mind, dreams are more likely to stay within a net; in dreams, they are more likely to leap from net to net. The mind, Hartmann believes, makes connections all the time, whether awake, asleep, or dreaming -- but the dreaming mind connects "more broadly, more widely."

"The waking mind is on a hunt," says Hartmann. It is goal-directed. "The dreaming mind is on an exploration." The dreaming mind's spreading connections help people think associatively, creatively, as Howe did with the sewing machine, and Stevenson did with Jekyll and Hyde.

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Allan Hobson will have none of it. "My challenge to the metaphor merchants," he says, rolling close in his office chair, "is, prove it! Show us scientifically! The whole point of science is to check belief. Rhetoric? I'm not interested. Literature? I'm not interested. Science is insurance against being fooled."

Hobson rolls around in his chair a lot, often aggressively, to emphasize a point or to ask a question. It is easy to imagine his delight nearly 30 years ago over that lecture title, "The Brain as Dream Machine," the title that tweaked establishment psychoanalysts and launched his career.

Hobson has graduated from a home lab to the neurophysiology department of Harvard Medical School, but in some sense he is still, at 60-plus, the boy who cut up snakes to challenge local wisdom. He spends his nights experimenting: he sometimes wears a "nightcap," a device made of a modified tennis headband with sensors for eye and body movement, to record his own REM sleep.

Then again, the man is not quite the boy. When he was around 40 he began keeping a dream log because, he says, he realized that he was going to die. Pressed on the subject of why a dream researcher, after nearly two decades of investigating dreams, finally starts recording his own, he has a variety of answers, ranging from "it's fun" to "it's an existential benefit." In 20-some years, he's recorded five or six thousand dreams in 102 volumes. And his published books are full of accounts of his own dreams.

Nonetheless, as a scientist he's not persuaded that he is recording messages from his unconscious. Hobson thinks that the science necessary to prove Hartmann and other psychoanalysts right is missing. In some cases, such as his "dream splicing" experiment, he believes the evidence flat-out contradicts their dream theories.

Dream splicing was an experiment designed by Hobson and Robert Stickgold, an assistant professor of psychiatry at Harvard Medical School, in which assistants took a variety of written dream reports, cut them up where the scenes shifted, and spliced them together at random. They left an equal number of dream reports whole. They then asked a panel of judges, all psychiatrists, to determine which dream reports had been spliced and which had been left whole.

His theory is that if dreams were truly individual, psychiatrists should be able to identify dreaming styles and thereby piece dream reports together accurately. The psychiatrists on the panel couldn't do it, and neither could Hobson. He concluded that dreams don't tell a coherent or useful story: that the metaphoric content dreamers find in their dreams, and the insight some dreamers gain upon waking, is false.

"Psychoanalysts' dream theory," says Hobson, "is the most fanciful, delicious, absurd theory that anyone's taken seriously for 100 years." And they've taken it seriously, Hobson believes, because it's so seductive. So comforting. How thrilling, after all, to believe that your subconscious creates while you sleep, that your subconscious heals psychic wounds, that something wiser than your conscious self is in charge.

In place of Freud's theory and Hartmann's theory and all the other psychoanalysts' theories, Hobson offers his own: a purely physiological theory that he calls "activation-synthesis."

In its simplest form, activation-synthesis, originally formulated by Hobson and his colleague Robert McCarley, another psychiatry professor at Harvard, comes down to this: we dream because of two processes, one called activation and the other called synthesis.

In the "activation" phase, the brain stem -- the lower, more primitive part of the brain -- blocks most incoming sensory data (smell, touch, sound) and also blocks motor impulses (the impulse to run, for instance). This is why someone dreaming about monsters does not physically react by running away. A dreamer is effectively paralyzed.

The cycles of REM sleep are governed by the balance of three neurotransmitters: serotonin, norepinephrine, and acetylcholine. (Neurotransmitters are chemicals that communicate messages from nerve cell to nerve cell.) While the body sleeps, the brain stem's production of serotonin and norepinephrine decreases almost to the point of inactivity. This raises the level of acetylcholine, which induces REM sleep -- and excites the visual, emotional, and motor centers that may be responsible for flooding the sleeping brain with images. Certainly, Hobson believes, there is a correlation between increasing acetylcholine and dreaming, but he can't yet say definitively that the one causes the other.

"Synthesis" takes place in the cortex, the seat of thinking and the higher part of the brain. The brain responds to the incoming flood of images by knitting them together as best it can, turning the random bits of data into a story, or what we know as a "dream." The reason dreams seem coherent to the dreamer -- at least at the time -- is because serotonin and norepinephrine, the chemicals that shut down to trigger the dreaming process, are also the chemicals that govern judgment. In other words, Hobson and McCarley believe, the very mechanism that enables dreaming prohibits us -- at least while we are dreaming -- from realizing how arbitrary our dreams really are.

In some sense this sounds anti-humanist. The process is automatic, the content random. Still, Hobson sees dreaming as a possible agent of creativity. We are nightly visited with spectacular visions -- "literary productions," as he puts it -- which, if we are good editors, we can transform into something else: a dream log, maybe even art.

Besides, Freud's theory of dreaming, says Hobson, is boring. Psychoanalysis is so limited. Everything is self-referential. "There are more things," he says, "than are dreamt of in your philosophy, Mr. Freud."

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But the frontiers of brain science are rapidly expanding, and even as Hobson distances himself from Freud's theories, others are distancing themselves from Hobson's. Cognitive scientist David Foulkes, in a 1996 article for the journal Sleep, reviewed the last 40-plus years of dream research and concluded that dreaming happens not just in REM sleep, but also in other phases.

That idea may challenge some of Hobson's most fundamental principles. "What I'll conclude for you," says Gerald Vogel, a critic of Hobson and director of the sleep-research laboratory at Emory University, "is that REM sleep is not a necessary condition for dreaming, and it is not a sufficient condition for dreaming. So therefore, unique physiological events can not explain dreaming. That's it in a nutshell, kid."

And if REM's "unique physiological events" cannot explain dreaming, then certainly, says Alfred Margulies, an associate professor of psychiatry at Harvard Medical School, "it's untenable to say that [neurophysiology] proves Freud wrong. Dream physiology is a lot less clear than folks would have it."

Still, most experts believe Hobson has made a significant contribution to our understanding of REM sleep. J. Christian Gillin believes that Hobson and other neurophysiologists have also strengthened traditional psychoanalysis. "In the '40s and '50s," says Gillin, "there were virtually no clinical trials ever conducted to determine the effectiveness of psychoanalytic theory. Today, nearly every theory is being tested empirically." So it seems that each side is at long last building a new methodological bridge, one that spans the conundrum of the brain-mind.

However, the two camps are still divided over content. Neurophysiologists believe that understanding the brain is our best shot at explaining the mind. Psychoanalysts believe the neurophysiologists are focused on the least interesting part of the story.

As an illustration, Ernest Hartmann claps loudly, startling a visitor. "There," he says, "I activated your cortex."

What's important at such times, he insists, is not that your brain was activated, but what you were thinking. What images came into your mind? To Hartmann, those questions are the key to understanding the cortex, the higher-level brain, and, ultimately, human nature. And that's where Hartmann thinks pure neurophysiology is lacking.

"All we can say now [about dreaming from a biological perspective]," says Hartmann, "is that [the brain] lights up differently during waking and dreaming. We can say the amygdala (the center of emotion) lights up during dreaming, but. . . . " He shrugs as if to say, So what?

Margulies agrees. Studying neurophysiology to the exclusion of psychology "is like a deaf Martian studying . . . how the human auditory system works. But the Martian could never understand Mozart."

Gillin has another metaphor: If dreaming is a drama, then "[neurophysiologists] have discovered where the house manager sits, and who turns on the lights, but they don't tell you what play will go on tonight, or who the actors will be."

"Psychology is a higher level of biology," says Hartmann. "Maybe someday biology will be able to describe what's happening in the cortex. But it will take 10,000 statements to say `defense mechanism.' Psychology is the shorthand way, and at the moment the best way, to describe what's going on in the cortex."

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In the end, many researchers in both fields believe that the overriding goal of dream theorists is not to pick sides, but to find one unifying theory that explains both brain and mind. That job may very well take professionals working from both the lab and the couch.

For all their differences, Hobson and Hartmann exemplify the trend toward unification. Each expresses a kind of intellectual joy upon hearing the other's theory of creativity. When Hartmann learns that Hobson believes dreaming allows for a random recombination of data that "opens up the system for creativity," the psychoanalyst sits back, looks skyward, and says, "I like that."

When Hobson is told of Hartmann's theory of dreaming as a "hyperconnective" state, he pauses, quieted, as if rolling the concept around his mind. "It's a genial theory," he says.

The argument between them is a central question in our age. Biology or metaphor? Science or art? Which discipline better explains the "truth" of dreaming? The debate being conducted here in Boston, in our heads and often over them, is a debate not only over dreaming, but over how we should be thinking about the big questions.

"I suspect in the long run," says Gillin, "we'll have to reconcile both theories." But in the meantime, the two camps are still a long way apart.

At the very end of one long interview, Hobson told me thoughtfully, maybe even wistfully: "All complex systems are noisy. Why shouldn't the brain be noisy?" He meant that dreams might be the static in a complex system, not the music. Hobson is still going into the woods, confronting the local wisdom, chopping up the snakes to figure out what makes them wiggle and what makes them stop.

Hartmann, in one of his last calls to me, said, "You left your scarf here," and then he paused. "You know what Freud would say? Freud would say you didn't want to leave." And metaphorically speaking, he was right.

Lisa Birk is a freelance writer living in Cambridge.