Women tend to recall their dreams more than men do. Their dreams also focus more on people and clothing. Work, sex and physical aggression tend to be the stuff of men's dreams.

So concludes one of the papers collected in "The New Science of Dreaming," a three-volume anthology of scholarly studies of dreams.

"I've always been fascinated by the properties of REM [rapid-eye movement] sleep, where most dreams come from," says Patrick McNamara, co-editor of the recently published "The New Science of Dreaming" (Praeger Publishers). "You've got a paralyzed body, the sexual system is active, and on top of this, you're forced to watch these dreams. Why would Mother Nature do this? What could possibly be the function of that? And that's what got me interested."

McNamara, an assistant professor of neurology at Boston University School of Medicine, is part of a growing academic field focusing on dreams -- where they come from and how they serve us. His co-editor, Dierdre Barrett, is an assistant professor of psychology at Harvard Medical School. A recent review in Library Journal predicted their book will become "a seminal work on the science of dreaming."

Topics covered in the nearly 1,000 pages include "Drugs and Dreaming," "The Social Network of Characters in Dreams" and "A Neurobiological History of Dreaming." The last essay suggests there might be some truth to a centuries-old notion that dreams are a form of temporary madness; neuro-imaging studies indicate a connection between the mental processes of schizophrenia and REM sleep.

Pondering the meaning of dreams has probably been going on since we lived in caves, but it wasn't until Freud published his "Interpretation of Dreams" that scholars took on the subject in earnest. The next big break came in 1953, with the discovery of REM sleep. But eventually, Freud's dream theories lost favor and, in the absence of any new advances, dream research lost a lot of momentum in the 1960s.

Academia may have lost interest in dreams, but people didn't. The mantle was taken up by self-professed dream interpreters, often New Age-type authors claiming the ability to tell you what that talking fish in your dream last night represents. Theories abounded about dreams' being a window to the future or past lives. Telling people what their dreams mean is big business; a quick check at Amazon.com finds a horde of "dream dictionaries" and "dream encyclopedias" promising to unlock the mysteries of your nighttime visions.

Rosalind Cartwright, a researcher at the Sleep Disorder Service and Research Center in Chicago, says she understands why these books are popular; it's only natural to want to figure out these strange stories going on in your head. But the premise of dream dictionaries is flawed -- few dream images have a common meaning.

In the scholarly world, Cartwright says the field of dream science existed somewhere on the fringe for a long time. Fellow academics used to look at her askance when she told them of her work. But when technology came along and gave researchers the ability to monitor brain activity, dream analysis entered a new era, and the field picked up steam in the 1990s.

"It's taken a very interesting turn recently; it was really a dead area for a while," Cartwright says. "Federal funding had dried up for this kind of work. Nothing much was new until we got brain imaging going."

"Now everyone wants to be in on the act, now that we know the brain is active 24 hours," she says. "There's a heck of a lot more going on in the brain than we ever dreamed of."

McNamara says one of the ideas researchers generally agree on now is that dreams "are not a random chaotic series of images, or deep Freudian secrets. Instead, they're patterns and ideas and they're simulations of real-world affairs. The dreaming mind is setting its own patterns."

As to exactly what purpose they serve, though, there are still a lot of different theories. Among them:

• Mood Regulators: Cartwright has conducted several studies, including one of recently-divorced people, to see how dreams affect mood. The more highly emotional and vivid the dreams, the more the subject's unconscious is working out problems, she says. As a result, the vivid dreamers tended to get over their divorce woes quicker than the others.
  
  "A lot of it depended on it how well the stories were constructed," Cartwright says.
  
  Though the studies were conducted over periods of months, she said, it was often possible to predict on the first night in the lab who would emerge first from their depression.

• Evolution Evolutionary: Biologists have also thrown their hats into the ring and say dreams are our way of dealing with future threats before they happen.
  
  For instance, McNamara says, male strangers in dreams often represent danger. The link, he says, comes from the time when the appearance of male strangers actually did mean the threat of pillage, rape and murder.
  
  "So the code 'male stranger = threat' is not something unique to the dream; it came from our evolutionary history," he said in an e-mail.

• Memory: Cartwright says researchers can monitor the brain activity of a subject during REM sleep and tell how well the brain is absorbing and sorting out new information from the subject's waking hours.
  
  "Those who have really dense eye movements are going to be absorbing that new learning," Cartwright says. "We can tell from what's going on in the sleep whether or not it's taking and whether it's going to be used."

Contact William Weir at bweir@courant.com.

Source: The Hartford Courant, Conn. Distributed by McClatchy-Tribune Information Services. Powered by YellowBrix.

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