(3 of 11)
Medical interest in the phenomenon began on the battlefield, where the devastating effects of chronic stress are unmistakable. During the Civil War, for example, palpitations were so commonplace that they became known as "soldier's heart." During World War I, the crippling anxiety called shell shock was at first attributed to the vibrations from heavy artillery, which was believed to damage blood vessels in the brain. This theory was abandoned by the time World War II came along, and the problem was renamed battle fatigue. By then the great Harvard physiologist Walter Cannon, along with Selye, had proved that psychological strain itself could cause dramatic hormonal changes and hence physiological symptoms. Selye showed that when the fight-or-flight response becomes chronic, as it does in battle, long-term chemical changes occur, leading to high blood pressure, an increased rate of arteriosclerosis, depression of the immune system and a cascade of other problems. "Humans have a fairly robust capacity to withstand a massive dose of acute stress," says Dr. Fred Goodwin, director of intramural research at the National Institute of Mental Health (NIMH). "Where we fall down is in our ability to mobilize for recurrent stressful episodes." Today the physiology of stress is being worked out in extraordinary detail. Says Neurochemist Jack Barchas of Stanford: "We have learned that even subtle behavior can markedly influence biochemistry" (see box).
War makes everyone anxious. But because most other kinds of stress are subjective, researchers have found it difficult to say just why a given situation is threatening. "I would die if I had to sit in a space capsule," says Boston University Psychiatrist Sanford Cohen. But while working with the early astronauts some 20 years ago, Cohen observed that "John Glenn just saw it as a job and went about it in a businesslike manner." Notes Benson: "A snowstorm is not stressful to a skier, but it is to someone who has an appointment across town."
In the early 1950s, University of Washington Psychiatrist Thomas Holmes determined that the single common denominator for stress, even for an astronaut, is "the necessity of significant change in the life pattern of the individual." Holmes found that among tuberculosis patients, for example, the onset of the disease had generally followed a cluster of disruptive events: a death in the family, a new job, marriage. Stress did not cause the illness, Holmes emphasizes—"It takes a germ"—but tension did seem to promote the disease process. Holmes discovered that merely discussing upsetting events could produce physiological changes. An experiment in which sample biopsies were taken before and after discussions of certain subjects showed that "we caused tissue damage just by talking about a mother-in-law's coming to visit," says Holmes. The example, he notes, is not facetious: "A person often catches a cold when a mother-in-law comes to visit. Patients mentioned mothers-in-law so often that we came to consider them a common