NWPF

News ArchivesRead News

Doctors Unravel The Placebo Effect Of Fake Parkinson's Disease Treatment

Friday July 18, 2014

Ben Wolford

Medical Daily - In a new study examining patients with advanced Parkinson's disease, neurologists say they've identified parts of the brain that control placebo effect, raising hopes of singling out people most susceptible.

But they're still very much in the dark about underlying causes of one of medicine's great mysteries. Some people, when given fake treatment, actually get better, but others, for whatever reason, do not. Stranger still, some people improve at the mere suggestion of future treatment.

The placebo effect is a problem for clinical researchers because they need to know which treatments work and which don't. When people respond well to treatments they aren't actually given or that don't actually work, it skews the results. That's why, for years, doctors have been trying to figure out how placebo works and why.

"While they may appear to be mysterious, placebo responses have discernible neurophysiological mechanisms," wrote the authors of a companion commentary inThe Journal of Clinical Investigation. To learn more about those mechanisms, neuroscientists at the Feinstein Institute for Medical Research in New York chose 45 patients with Parkinson's disease for a double-blind study. All of them would receive brain surgery, but only 22 would receive actual treatment. The other 23 were given fairly routine operations designed to do nothing.

The doctors weren't looking for signs of placebo effect — they already knew it would happen. Patients with Parkinson's disease, the second most common neurological illness behind Alzheimer's, have previously shown an incredible sensitivity to the idea of treatment. A 2001 study illustrated that dopamine released at the expectation of possible healing had healing benefits by itself. "Expectations," doctors wrote in another study, "have a strong influence on the subsequent emotional experience of both" pain relief and reward processing.

Here's the interesting thing: Those 16 patients had very little activity before surgery in the parts of the brain that are activated by placebo. The other seven had more activity in the region all along. So that's the good thing — research doctors may now have something to look for when they want to weed out placebo-receptive test patients.

The bad thing is researchers still have no clue how a little dopamine and anti-depressant brain activity relates to improved motor function. "The final effector pathway remains obscure," wrote Mariya V. Cherkasova and A. Jon Stoessl in their commentary. But they say one thing is more clear from the study — expectation didn't have anything to do with it. The knowledge of participation in clinical trials did not induce placebo effect.

In a sad coda to the study, one year after their placebo brain surgeries, the Parkinson's patients were unblinded. That is, their doctors revealed that they had been in the sham surgery group and not the treatment group. Immediately, the parts of their brains that are activated by placebo reverted to their normal state. With that, their small gains in motor functioning disappeared, too.

Wolford, Ben. (18 July 2014). Medical Daily. Doctors Unravel The Placebo Effect Of Fake Parkinson's Disease Treatment. http://www.medicaldaily.com/doctors-unravel-placebo-effect-fake-parkinsons-disease-treatment-293760

Recent News

May 2 - What's Good For The Heart Is Good For The Brain
Apr 29 - Press Release: FDA approves first drug to treat hallucinations and delusions associated with Parkinson’s disease
Apr 28 - Dopamine-making neurons can be chemically controlled in animal model of Parkinson's
Apr 25 - Lifestyle: Dating with Disease
Apr 25 - Scientific breakthrough in fight against Parkinson's and Alzheimer's
Apr 20 - Breakthrough Parkinson's disease blood test
Apr 12 - Tissue biomarker for dementia with Lewy bodies and Parkinson’s disease
Apr 11 - Yoga for Every Body: Experts say yoga can ease pain and improve mobility for people with neurologic conditions
Apr 9 - Commonly prescribed Parkinson's drugs up risk of compulsive gambling, shopping, binge eating, hypersexuality
Apr 7 - Pfizer and IBM Launch Innovative Research Project to Transform Parkinson's Disease Care
Apr 7 - Parkinson's Drug Highly Effective for Resistant Depression
Apr 5 - Speech therapy program helps Parkinson’s patients regain speaking ability
Apr 4 - New research maps out pesticide exposure and Parkinson's disease in Nebraska
Apr 4 - The rogue immune cells that wreck the brain
Mar 28 - Chemists identify structure of protein that forms fibrils in Parkinson's patients
Mar 25 - UPDATE 1-FDA staff says Acadia's drug for Parkinson's disease psychosis is effective
Mar 23 - The virus that could cure Alzheimer's, Parkinson's and more
Mar 21 - Antipsychotic drugs may do significantly more harm to Parkinson's disease patients
Mar 21 - Rosacea Might Boost Parkinson's Risk: Study
Mar 21 - Apple CareKit Could Completely Change What It's Like To Live With Parkinson's Disease & Epilepsy