MONDAY, Aug. 2 (HealthDay News) -- The expectation of receiving an active drug increases the likelihood of a strong brain chemical response when Parkinson's disease patients are given a placebo, finds a Canadian study.
The study included 35 people with mild to moderate Parkinson's disease who were being treated with the drug levodopa. On the first day of the study the patients underwent an initial PET brain scan. They were then given levodopa and had another brain scan.
On the second day, the patients were told they had either a 25 percent, 50 percent, 75 percent or 100 percent chance of receiving levodopa before they underwent a third brain scan. However, all of them received a placebo.
Among patients who were told they had a 75 percent chance of receiving levodopa, the brain scans showed a significant release of the neurotransmitter dopamine in response to the placebo. This did not occur in the other patients, according to the report published in the August issue of the journal Archives of General Psychiatry.
http://news.yahoo.com/s/hsn/20100802/hl_hsn/expectationmayaffectplaceboresponseinparkinsonspatientsI heard this story on NPR today and found it kind of interesting.