The Wall Street Journal:
Perceptions of pain can be changed by distorting the view of the affected body part, a new study finds, opening a fresh window onto the psychological side of pain.
Researchers affixed a heat-producing device to the left index fingers of 18 volunteers. A mirror was set up so that when the subjects looked toward their left hand what they saw was really a reflection of their right hand. (To complete the effect, the right index finger got its own non-functioning thermode.) Then they started turning up the heat, slowly.
Read the whole story: The Wall Street Journal