People who buy "subliminal" audiotapes to help lose weight, stop smoking, have higher self-esteem and a better sex life are wasting their money, a new study suggests.
The self-help tapes had no significant impact on 78 volunteers who listened to them at home for five weeks, says a University of California-Santa Cruz psychologist.The tapes are called subliminal because they convey inaudible positive messages over and over - for example, "I like myself and others" and "I have enormous concentration ability." The conscious brain "hears" only pleasant sounds, say, ocean waves.
But the listener's unconscious brain can "hear" the motivational messages and be molded by them, tapemakers say.
For example, a tape available in San Francisco "New Age" stores says that "by saturating your subconscious mind with positive supportive affirmations, it's possible to change unwanted habits and beliefs and effect major positive changes in your life."
Is it good medicine - or mumbo-jumbo?
To test similar claims, UC-Santa Cruz psychologist Anthony Pratkanis got 78 volunteers, ages 18 to 60, to listen to subliminal tapes. First he subjected them to tests, including ones for memory and self-esteem. Then each participant received a commercially available tape labeled either "subliminal memory improvement" or "subliminal building self-esteem."
They listened to the tapes for five weeks at home. But Pratkanis tricked his volunteers: He deliberately switched the labels on half the tapes.
For example, many volunteers who thought they were getting tapes to boost memory were actually receiving tapes to raise their self-esteem. After the study Pratkanis repeated the psychological and memory tests, and gave the volunteers a questionnaire asking whether the tapes worked.
The result: thumbs down on subliminal tapes.
"Extensive statistical analysis of the results showed that listening to the tapes did not affect the subjects' performance on any of the 14 tests," said UC-Santa Cruz spokeswoman Noreen Parks.
Oddly, volunteers who received "self-esteem" tapes were almost three times as likely to say the tapes improved their self-esteem as those who got "memory" tapes.
Wishful thinking explains much of the multimillion-dollar subliminal tape industry, Pratkanis argues, saying: "People are always pulling me aside at cocktail parties and asking me in hushed tones, `What about this subliminal stuff?' They want to believe in it."
But makers, sellers and users of self-help tapes defend the products.
"Most people who use them feel they're effective," said George Thompson, owner of Mind Over Matter, a Portland company that markets about a dozen tapes on topics ranging from smoking to weight control. "We have lots of customers who write us testimonials and tell us the products work."
Kim Franz, 41, is a satisfied customer. She says the tapes gave her the "fighting attitude" she needed to handle serious illnesses and the death of her husband.
But Pratkanis is skeptical. He said, "Consumers should demand the same evaluation of self-help tapes as they would any other therapeutic product."