Sweet Dreams

You're in an airplane five miles above the earth, travelling 600 miles an hour toward nowhere in particular. Suddenly the plane cracks wide open. The captain tells you there's nothing to worry about, but all around you passengers are falling out of the plane. Now you're falling, too, twisting slowly end over end. A woman floats by waving to you as she opens her parachute. You look up and all the passengers are opening parachutes. You look down and suddenly the earth seems very close. You don't have a parachute. You wait helplessly for the ground to swallow you up...

Throughout history, dreams have remained some of the most talked about, written about and least understood human phenomena. Their bizarre manifestations are sources of comfort and pain, happiness and terror. Dreams temporarily permit us to escape the confines of our bodies, engage in private, surrealistic melodramas and awaken the next morning with no visible effects. But why do we dream? So far, all explanations have basically been conjectures.

For the first half of this century, Dr. Sigmund Freud's doctrine--which stressed dreams as mental catharsis and wish-fulfillment, with heavy emphasis on sexuality--was accepted almost verbatim by many psychiatrists. A Freudian analyst might say a man who had the above dream sub-consciously is worrying about his masculinity, resenting his father and coveting his mother. Although few psychiatrists today are Freudian purists, the concept that dreams represent fulfillment and mental catharsis remains a cornerstone of dream interpretation.

But Dr. J. Allan Hobson, professor of Psychiatry at the Medical School, says the psychological importance of dreaming has been overplayed. Hobson, who directs the Laboratory of Neurophysiology at the Massachusetts Mental Health Center in Boston, says dreaming is more physiological than psychological. He refutes much of Freud's reasoning: "Freud says if you didn't have emotional conflicts you wouldn't dream--this is ridiculous. I would be much less likely to regard dreams as psychological. Freud would describe a man who couldn't remember his dreams as repressing hidden guilt feelings. I would say that he simply couldn't remember his dreams."

Hobson and co-researcher Dr. Robert W. McCarley, professor of Psychiatry, have been investigating the physiological aspects of dreaming for 12 years at the mental health center, by focusing on the relationship between Rapid Eye Movement (REM--the active dreaming stage of sleep) and a "dream center" in the brainstem. Since 1953, when REM was discovered, most psychiatrists have believed that dream images from the frontal brain cause these quick, darting eye movements. Hobson and McCarley's "activation-synthesis," theory maintains that the opposite is true.

This theory, presented three years ago in the American Journal of Psychiatry, maintains that periodically during sleep REM activates a dream center in the brainstem. For example, if the eyes look to the left, the dream center may receive a message for the body to turn left. The dream center then relays this command to the body. Although the body does not actually move left, it sends a message to the frontal brain indicating that it moved. But the movement is not always so simple as turning left. Because the eyes are not actually seeing, the messages they transmit are garbled and incomplete, and often call for impossible movement such as flying. The bizarre images in dreams, says Hobson, are simply the brain's attempt to make sense out of nonsense.

Hobson rejects the Freudian notion that dreams are essential because they offer an outlet for suppressed emotions. Dreaming is simply the result of REM, Hobson says. "Babies for example, have much more REM than adults--this is not because infants have an abundance of suppressed emotions and hidden remorse; it is because they are learning very much very fast. Similarly, when REM falls off with old age, this does not mean old age, this does not mean old people have any less anxiety than any one else," he adds.

Hobson has conducted extensive research on cats, which he says confirms the existence of the independent dream center in the mammalian brainstem. "REM occurs in cats when the entire brain except the brainstem has been destroyed," he says. The cat research has shown that REM causes the brain to create the dream and not vice-versa, Hobson says. "Obviously, we cannot tell if a cat is actually dreaming, but by inserting a microscopic electrode into a cat's brain, we can measure the electrical signal as it passes along a single nerve cell--the impulse in the eye fires before the impulse in the brain." Hobson adds that because all mammals have roughly the same brain structure, it is fair to assume the basic REM process works the same in humans and cats.

Hobson's and McCarley's "activation-synthesis" theory provoked a heated controversy in the American Journal of Psychiatry. "The editor of the journal told us our article generated more letters than any in the history of the journal," Hobson says. Much of the response was negative, Hobson says, in part because many people misinterpreted the theory.

"A lot of people objected to our philosophical views--they thought we were saying that dreams don't mean anything. This isn't true. Our theory does not exclude psychological interpretation of dreams--it states that the basic process of dreaming is physiological," he adds.

Hobson says another reason for the criticism is that, "people would rather not have you rock the boat." Even though few psychiatrists still adhere to strict Freudian analysis, "it takes a lot of work to come out strongly against the established theories, and people who have practices are often reluctant to do so," he adds.

The controversy has died down since the fireworks three years ago. But Hobson and McCarley plan to take part in a debate next spring in New Orleans that Hobson says he hopes will stir up the controversy. "This type of thing is good for psychiatry," he says. When people refuse to revise their ideas, Hobson says, "psychiatry is in trouble."