Parkinson’s Disease Patients Show Improved ‘Reward Learning’ From Placebo Effect, Researchers Say

A placebo used in a study about Parkinson’s disease treatment stimulated learning-related brain activity just as well as the actual Parkinson’s medication, according to researchers from Columbia University and the University of Colorado at Boulder. The details of the new Parkinson’s disease research have been published in the journal Nature Neuroscience. The study’s findings hold up results from previous studies that found that patients with Parkinson’s disease who have positive expectations of their treatment demonstrate greater improvement in their brains.

Medical News Today calls the findings of the Parkinson’s disease study, “a clear example of how psychology and medicine interact” that demonstrates “the powerful effect of expectation on the brain.”

Known as “the placebo effect,” people can sometimes respond to treatment that includes no medication if the patient believes they are taking medication. Tor Wager, an associate professor of psychology and neuroscience, and co-author of the study, believes that the new Parkinson’s research, which was funded by the Michael J. Fox Foundation for Parkinson’s Research,”highlights important links between psychology and medicine.”

Parkinson’s disease is a motor disorder. It is believed to occur when a person’s brain loses dopamine-producing cells. Dopamine is a naturally occurring brain chemical that controls reward and pleasure and regulates emotional responses, as well as bodily movements. Because of the loss of dopamine-producing cells, Parkinson’s disease sufferers have difficulties with “reward learning,” according to the study’s authors, since this form of learning requires a dopamine release in response to positive rewards offered after particular actions.

One of the ways physicians treat patients with Parkinson’s disease is to give them dopamine-boosting medication, according to the authors. For the study, Wager and his team compared using this medication against using a placebo. Parkinson’s disease patients were tasked with playing a computer game that centered around reward learning. While playing the game, the participants had functional magnetic resonance imaging (fMRI) scans taken of their brains.

The participants in the Parkinson’s placebo-based study had their learning measured as they discovered, by trial and error, which of two symbols would lead to a reward. The rewards that were offered were receiving money and “avoiding the loss of money,” according to Medical News Today. The patients with Parkinson’s disease played the computer game three different times. One time, orange juice was given and acted as a placebo. Another time, orange juice with medication was given. The participants with Parkinson’s disease did not know which was which. On another try, they were given neither a placebo, nor medications.

The researchers compared the results of the game to the fMRI results. They found that the dopamine-rich areas of the participants’ brain were just as active when they took the placebo as when they took the medication. Some holistic practitioners are questioning whether or not the researchers took into account any effect the nutrients in the orange juice itself might have had on the positive results recorded from the placebo part of the study.

The researchers found the results of their placebo-based study significant and full of potential.

“Recognizing that expectation and positive emotions matter has the potential to improve the quality of life for Parkinson’s patients, and may also offer clues to how placebos may be effective in treating other types of diseases,” Wager said.

[Photo via Pixabay]