Brain's reward system helps drive placebo effect

"Want to maximize the placebo effect? A good way to do this, according to a new study, is to tell someone they have a decent chance of getting the real treatment instead of a fake pill, but keep them guessing. In the study, Parkinson's disease patients given a placebo after being told they had a 75 percent chance of receiving an active drug produced significant amounts of dopamine, a chemical key to the brain's reward system that is scarce in the brains of patients with this disease. But no d...