In a clear example of how psychology and medicine interact, a new study of Parkinson’s disease shows the powerful effect of expectation on the brain. In the study, participants’ learning-related brain activity responded as well to a placebo as it did to real medication.

Share on Pinterest Expectation of treatment can boost the brain as strongly as dopamine drug in Parkinson’s – a disease that gradually diminishes ability to get on with normal daily life.

Researchers from the University of Colorado at Boulder (CU-Boulder) and Columbia University, New York, NY, report their findings in the journal Nature Neuroscience.

Previous studies have suggested that the brain systems affected by Parkinson’s disease can respond to patients’ expectations about treatment.

The new study explains how the placebo effect – where people believe they have received the active drug – works by activating dopamine-rich areas in the brain of people with Parkinson’s disease.

Study co-author Tor Wager, an associate professor of psychology and neuroscience at CU-Boulder, says the study “highlights important links between psychology and medicine.”

Parkinson’s disease is a motor disorder that occurs when the brain loses cells that produce dopamine – a brain chemical that helps control reward and pleasure and also regulates movement and emotional responses.

The disease has four main symptoms: trembling in the hands, limbs, jaw and face; stiffness of the trunk and limbs; slowness of movement; and problems with balance and coordination. The symptoms of Parkinson’s disease, which rarely strike before the age of 50, gradually worsen to the point where doing normal everyday things like, walking, talking, eating and taking care of oneself becomes very difficult.