In one startling drug study in the 1980s, a young woman who had been virtually homebound by the energy-sapping effects of chronic fatigue syndrome had a miraculous recovery.
But, it wasn't the drug that cured the patient – she was in the trial group that was taking sugar pills. It was the "placebo effect," — a well-documented phenomenon that has intrigued doctors for decades.
When patients believe a drug will help them, they sometimes heal themselves.
"She and her parents were so excited about her profound improvement," said Janet Dale, a staff scientist at Clinical Investigation at the National Institute of Allergy and Infectious Diseases. "And she sustained her health and continued to be well."
It's human nature, explained the study scientists, who reported nearly 50 percent of the participants on placebos got better.
But now, with advances in neuroscience, researchers at Columbia University and the University of Michigan have been able to see how the placebo effect works.
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.
One day doctors might be able to determine which patients are more responsive to placebos and use lower doses of powerful medicines that can cause side effects and allergies.
The study, which was published in Proceedings of the National Academy of Sciences, "is another piece of evidence that the person is not just changing the way you say you feel, but how it is processed in the brain," said Wager.
The word "placebo" is Latin for "I will please." Placebos like sugar pills, distilled water or saline solutions have been used for decades in drug research and by doctors.
In a 1955 ground-breaking paper, "The Powerful Placebo," researcher H.K. Beecher concluded that one-third of all patients responded to a placebo.
In later studies, when patients were told they were taking stimulants, their blood pressure and pulse rates rose; when they thought they were taking sleeping pills, they fell.
But the most significant research in placebos has been seen in the treatment of pain relief. In some studies up to 75 percent of patients responded to sugar pills, according to the Food and Drug Administration.
"Placebo groups are included in virtually every major clinical trial, which is a testament to their importance," said Wager. "Only in the past few years have scientists developed the tools to directly investigate how placebos work in the human brain."
Doctors have used the chemical opiate morphine to treat pain for two centuries, so scientists like Wager have theorized that if morphine "mimics what the brain does naturally, the brain must have its own internal chemical."