A Placebo Can Work If You Have The Genes For It

摘要

For the first time, a gene is being linked to increased susceptibility to the placebo effect, the mysterious capacity some people have to benefit from sham treatments.rnThe gene might not play a role in our response to treatment for all conditions, and the experiment involved only a small number of people. Nonetheless, the discovery is a milestone in the quest to understand this phenomenon, which often blurs the results of clinical trials "To our knowledge, it's the first time anyone has linked a gene to the placebo effect," says Tomas Furmark of Uppsala University in Sweden.rnHe and his colleagues recruited 25 people with an exaggerated fear of public humiliation, otherwise known as social anxiety disorder.rnParticipants had to give a speech at the start and end of an eight-week treatment - which unbeknownst to them and their doctors, was actually a placebo.rnTen volunteers responded to the placebo much better than the rest. By the end of the experiment, their anxiety scores had halved, whereas the others' stayed the same. Brainrnscans also showed that activity in the amygdala, the brain's "fear" centre, had dropped by 3 per cent.