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Almost everyone is afraid of something—snakes，heights，public speaking and so on.
It is normal and can even be helpful to experience fear sometimes. In dangerous situations，fear can keep our bodies alert（警醒的） so that we can act quickly to protect ourselves.
But for some people，fear develops into a"phobia"which is a strong and unreasonable fear of something. For example，the majority of us feel a little scared when looking down from a tall building. But people with height phobia may have trouble breathing, feel dizzy or turn down a great job just because the company is on the 20th floor.
Phobias can prevent you from living a normal life. "People with spider phobia would stay out of their home or dormitory room for days if they thought a spider was present，" Katherina Hauner，a researcher at Northwestern University US, told ABC news. This is why scientists have been trying to find a cure for this disease.
Since fear comes from experience—from what we are told，what we see others experience and what happens to us ﹣ some scientists think if they can"rewrite"these unpleasant memories，they might be able to help people overcome their phobias.
In a study by Hauner and other scientists participants with spider phobia were asked to first touch a spider with a paintbrush. Seeing that it was not actually dangerous，they then tried touching it while wearing a glove. Finally，they could hold it with their hands.
Certain medicine has also been found to be helpful. Back in 2010，researchers at the University of Hiroshima Japan injected（ 注射） a special medicine into a fish—who was afraid of light—to turn off the fear center in its brain. From then on, the fish no longer feard light.
While the search for solutions to phobias is making great progress，it's an open question whether getting rid of fear is good. Some people want to use these methods to make soldiers fight harder in wars by taking away their sense of fear. Dave Smithson of the Charity Anxiety UK thinks that's a bad idea. "It's fear that prevents us from doing crazy things. "he says. "There's a name for people who don't have fear of consequences: psychopaths（精神变态）".
