03/28/2008 02:44 am ET Updated Nov 17, 2011

The Placebo Effect, Explained: Pain Relief Is One Part Drugs And One Part Hope

When volunteers were convinced they were receiving pain medicine, their brains actually released natural relief, or opioids.

"It is the first time we have been able to directly observe placebo-induced pain relief," said neuroscientist Tor Wager of Columbia University, whose findings also showed that drug effectiveness is enhanced by the power of the mind.

"We usually think a drug does something to you, but there are examples in which the drug doesn't do anything unless we have the correct belief," he said. "You need both the chemical and faith that the drug will work."

"We're not there yet," said Wager, but this discovery could change the treatment of pain and disease.

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