Altered States

It's well known that some people are more responsive to hypnosis than others. Hypnotizability, experts say, is a trait, like eye color. As a rule, the more "absorbed" a person is able to get in things--movies, sunsets, daydreams--the more hypnotizable he is. (Researchers use standardized measures to screen subjects.) People who describe themselves as more trusting of others tend to be more hypnotizable, says Spiegel, while those who are very logical and never take anything at face value tend to be less so.

Several studies using positron emission tomography (PET) have looked at what goes on in the brain during hypnosis. In one, hypnotized subjects had their hands immersed in "painfully hot" water but were told it was comfortably warm. This not only altered their perception of the pain but also altered blood flow in pain-related parts of the brain. In another study, highly hypnotizable people were shown a black-and-white pattern and asked to see color. The results: the regions of the brain normally activated during color perception were activated in the hypnotized subjects. "It's not just a fantasy," says Spiegel. "It's not just telling people things because that's what you think they want to hear. If you think you are seeing color, you actually see it, and your brain acts as though it's seeing it." It's easy to see why, in the field of hypnosis these days, nobody is getting sleepy.

WITH SARAH SENNOT IN LONDON

© 2004