Study Verifies Power of Positive Thinking

[Guest guest]

Source: http://www.livescience.com/humanbiology/ap_051128_placebo.html

 

Study Verifies Power of Positive Thinking By Lauran Neergaard Associated Press

WASHINGTON (AP) -- Your medicine really could work better if your doctor

talks it up before handing over the prescription. Research is showing the

power of expectations, that they have physical -- not just psychological --

effects on your health. Scientists can measure the resulting changes in the

brain, from the release of natural painkilling chemicals to alterations in

how neurons fire. Among the most provocative findings: New research suggests

that once Alzheimer's disease robs someone of the ability to expect that a

proven painkiller will help them, it doesn't work nearly as well. It's a

new spin on the so-called placebo effect -- and it begs the question of how

to harness this power and thus enhance treatment benefits for patients.

" Your expectations can have profound impacts on your brain and your health,''

says Columbia University neuroscientist Tor

Wager. " There is not a single placebo effect, but many placebo effects,''

that differ by illness, adds Dr. Fabrizio Benedetti of Italy's University of

Torino Medical School, who is studying those effects in patients with

Alzheimer's, Parkinson's disease and pain. The placebo effect is infamous

from studies of new medications: Scientists often given either an

experimental drug or a dummy pill to patients and see how they fare.

Frequently, those taking the fake feel better, too, for a while, making it

more difficult to tease out the medication's true effects. Doctors have

long thought the placebo effect was psychological. Now scientists are

amassing the first direct evidence that the placebo effect actually is

physical, and that expecting benefit can trigger the same neurological

pathways of healing as real medication does. Among them: --University of

Michigan scientists injected the jaws of healthy young men with salt water to

cause

painful pressure, while PET scans measured the impact in their brains.

During one scan, the men were told they were getting a pain reliever,

actually a placebo. Their brains immediately released more endorphins --

chemicals that act as natural painkillers by blocking the transmission of

pain signals between nerve cells -- and the men felt better. To return to

pre-placebo pain levels, scientists had to increase the salt-water pressure.

" Our brain really is on drugs when we get a placebo,'' says co-researcher

Christian Stohler, now at the University of Maryland. More remarkable, some

especially strong placebo responders suggest " many brains can actually

stimulate that (pain-relief) system more.'' Italy's Benedetti gave

Parkinson's patients a placebo and measured the electrical activity of

individual nerve cells in a movement-controlling part of the brain. Those

neurons quieted down, a decrease in firing of about 40 percent that

correlated with

a reduction in patients' muscle rigidity -- they moved more easily. To

further prove the power of belief, Benedetti hooked pain patients to a

computerized morphine injection system. Sometimes the computer administered a

dose without them knowing it; sometimes a nurse pretended to give it. The

morphine was up to 50 percent more effective when patients knew it was

coming. Likewise, Parkinson's patients moved much better when they were told

that doctors had turned on a pacemaker-like implant in their brains, which

blocks tremors, than when it was turned on covertly. But in a similar

experiment with Alzheimer's patients suffering pain, Benedetti found no

difference between covert or expected dosing. The results are preliminary, he

cautioned a meeting of the Society for Neuroscience last month. But it

appears that because Alzheimer's robs patients of the cognitive ability to

expect a benefit, they need higher doses of painkillers to get as

much relief as non-demented patients. Placebos aren't a substitute for real

medicine. But the research suggests maybe doctors should try to manipulate

patients' treatment expectations, for at least some hard-to-treat conditions.

" The bigger question is how do we capitalize on the placebo effect,'' said

Dr. Helen Mayberg of Emory University, whose studies suggest some

antidepressants have a " placebo-plus'' activity in the brain. " There may be a

phenomenon we all have access to.'' Study: Optimists Live Longer

 

 

 

 

Shopping

Find Great Deals on Holiday Gifts at Shopping