Antworten für [Recent Tests-Bộ VOL] - The Placebo Effect

With the right encouragement, your mind can convince the body to heal itself. What is the mysterious force that can do this?

Want to devise a new form of alternative medical treatment? No problem. Here's the recipe. 1As a practitioner, be warm, sympathetic, reassuring, and enthusiastic. Your treatment should involve physical contact, and each session with your patients should take at least half an hour. Encourage your patients to take an active part in their treatment and understand how their disorders relate to the rest of their lives. Tell them that their own bodies possess the power to heal. Get them to pay you well. 2Describe your treatment in familiar words, but embellish with a hint of mysticism: energy fields, energy flows, energy blocks, meridians, forces, auras, rhythms, and the like. Refer to the knowledge of an early age: wisdom carelessly swept aside by the rise of blind mechanistic science. Oh, come off it, you're saying. Something like that couldn't possibly work, could it?

3Well yes, it could - and often well enough to earn you a living. And a very good living if you are sufficiently convincing or, better still, really believe in your therapy. 4Many illnesses get better on their own, so if you are lucky and administer your treatment at just the right time, you'll get the credit. But that's only part of it. Some of the improvement really would be down to you. Not necessarily because you'd recommend acupuncture rather than chamomile tea or used this crystal as opposed to that pressure point. Nothing so specific. Your healing power would be the outcome of a paradoxical force that conventional medicine recognizes but remains oddly ambivalent about: the placebo effect.

Placebos are treatments that have no direct effect on the body, yet still work because the patient has faith in their power to heal. Most often the term refers to a dummy pill, but it applies just as much to any device or procedure, from a sticking plaster to a crystal. The existence of the placebo effect implies that even a complete fraud could make a difference to someone's health, which is why most practitioners of alternative medicine are sensitive about any mention of the subject. 5-6In fact, the placebo is a powerful part of all medical care, orthodox or otherwise, though its role is often neglected and misunderstood.

7At one level, it should come as no surprise that our state of mind can influence our physiology: anger opens the superficial blood vessels of the face; sadness pumps the tear glands. But exactly how placebos work their medical magic is still largely unknown. Most of the scant research to date has focused on the control of pain, because it's one of the commonest complaints and lends itself to experimental study. Here, attention has turned to the endorphins, natural substances produced in the brain that are known to help control pain. "Any of the neurochemicals involved in transmitting pain impulses or modulating them might also be involved in generating the placebo response," says Don Price, an oral surgeon at the University of Florida.

That case has been strengthened by the recent work of Fabrizio Benedetti of the University of Turin, who showed that the placebo effect can be abolished by a drug, naloxone, which blocks the effects of endorphins. Benedetti induced pain in volunteers by applying a pressure cuff on the forearm. He did this several times a day for several days, using morphine each time to control the pain. On the final day, without saying anything, he replaced the morphine with a saline solution. This still relieved the subjects' pain: a placebo effect. But when he added naloxone to the saline and blocked the endorphins, the pain relief disappeared. Here was direct proof that the relief of pain by a placebo is carried out, at least in part, by these natural opiates.

8Though scientists don't know exactly how placebos work, they have accumulated a fair bit of knowledge about how to trigger the effect. 9A London rheumatologist found, for example, that red dummy capsules made more effective painkillers than blue, green, or yellow ones. Research on American students revealed that blue pills make better tranquilizers than pink, a color more suitable for stimulants. Even branding can make a difference: 10If Aspro or Tylenol are what you like to take for a headache, their chemically identical generic equivalents may be less effective.

11It matters too how the treatment is delivered. Decades ago, when the major tranquilizer chlorpromazine was being introduced, a doctor in Kansas categorized his colleagues according to whether they were keen on it, openly skeptical of its benefits, or took a "let's try and see" attitude. 12His conclusion: the more enthusiastic the doctor, the better the drug performed. A recent survey by Ernst on doctors' bedside manners turned up one consistent finding: Physicians who adopt a warm, friendly, reassuring manner are more effective than those whose consultations are formal and do not offer reassurance.

"Warm, friendly, and reassuring" are precisely what alternative treatment is all about, of course. 13Many of the ingredients of that opening recipe - the physical contact, the generous swaths of time, the strong hints of supernormal healing power - are just the kind of thing likely to impress patients. "It's hardly surprising then, that complementary practitioners are generally best at mobilizing the placebo effect," says Arthur Kleinman, professor of social anthropology at Harvard University.