BEIJING, Nov. 11 (Xinhuanet) -- Do you believe placebo effect? Can a dummy pill or a faked treatment make people feel better? The answer is yes. Two words explain how it works: "I believe." It's the mind's power to change physical symptoms, such as pain, anxiety and tiredness, according to medical experts.

    Placebo's healing effect has been demonstrated in just the past few weeks. In tests of a new drug to relieve lupus symptoms, about a third of patients felt better when they got dummy pills instead of the drug.

    In 1955, H.K. Beecher, found that 32 percent of patients responded to a placebo, which is viewed as groundbreaking.

    Later studies found that dummy pills could raise pulse rates, blood pressure and reaction speed when people were told they had taken a stimulant; the opposite occurred when people were told that a drug would make them drowsy.

    Scientists do not always know how it works. But there are many possible ways. Brain imaging shows that beliefs can cause biological changes and affect levels of chemical messengers and stress hormones.

    Emotions also can trigger physical changes. Take the case of a child with croup. Crying tightens the airways and makes it tougher to breathe.

    (Agencies)