How many psychologists does it take to change a light bulb? One.
But it has to want to change very, very much.
It turns out that this old joke brings more than chuckles. It is the rationale for the hottest research in motivational psychology.
Scientists are beginning to take more seriously the idea that there is a relationship between good health and good thoughts. Some think that optimism may be a potent treatment for a variety of ailments.
"The only person who should do research on optimism is a born pessimist like me," said Martin Seligman, a professor of psychology at the University of Pennsylvania in Philadelphia, who is exploring whether a sunny disposition can enhance physical health. "We are teaching people to dispute their own catastrophic thoughts."
Seligman, who wrote Learned Optimism (Alfred A. Knopf), is only one of many who are exploring the interface of the mind and body. They range from those who believe that good thoughts can ease the pain of cancer to those who have linked bad thoughts to a decrease in the body's immunity to disease.
For example, researchers in the past decade have found that depression alters the effectiveness of key cells that fight disease, yet no one is quite sure what, if anything, that means.
Seligman says research shows that pessimistic people have weaker immune systems, are more prone to colds and flu and have more major health problems after age 50. Their bodies are also less likely to fight off killer diseases such as cancer.
Can people worry themselves sick?
University of Pennsylvania researcher Gregory Buchanan believes so. He gathered decade-old video footage from another study that looked at the effects of anxiety-ridden type A behavior on heart attack victims. Of the 122 subjects studied, 61 were still alive. Buchanan, a colleague of Seligman's, then used a technique called Content Analysis of Verbatim Explanations _ a linguistic analysis of the taped comments _ to determine whether an individual was a pessimist or an optimist.
According to Buchanan, more of those who were identified as pessimists had died. Those who ranked within the top 25 percent of the most negative had the highest death rate: 26 of 31 had died. By contrast, only 10 of the 31 who ranked as the most optimistic had died.
Buchanan said that while the findings were exciting, they needed more work. He said there are many ways to explain why optimists seem to live longer. For example, pessimists often are less likely to change their lifestyles even if activities such as smoking put them at greater risk of heart attack. Or, Buchanan said, pessimists' dire outlook may put added stress on the heart. Or it may be that pessimism triggers some yet-to-be-explored biochemical reaction that plays havoc with the body's hormones.
There is also some evidence that a positive outlook may have a healthy effect on the body. Sandra Levy and fellow psychologists at the University of Pittsburgh studied 40 seriously ill cancer patients who received chemotherapy and radiation. Half the group also went through a 12-week course of cognitive therapy designed to improve attitudes by getting them to modify their thoughts. Months later, scientists found the patients who underwent therapy had much higher levels of natural killer cells, one of the main soldiers of the immune system, than those who did not get the therapy. The group also lived, on average, a few months longer than the one that didn't receive therapy.
Whether optimism really breeds good health is anybody's guess, but experts are sure that pessimism breeds pessimism. Seligman and others believe that a person learns very early whether to view the glass as half full or half empty. Very often the lesson is taught by parents. And how a person thinks about life changes little as the person grows older, they say.
Still, can a pessimist change her spots?
Yes, says Seligman and argues that his experiment shows two things: People who feel they have control tend to be optimistic. They also tend to be mentally healthier.
He's always eager to turn a pessimist into an optimist. If you can't achieve real control, he says, there are ways at least to minimize bad thoughts. In his book, he describes two techniques. The first is simply to distract yourself. If that doesn't work, start disputing your beliefs. In time, a more positive way of thinking may emerge.