[olsen]

Study to determine whether one would respond to a placebo or not in relieving pain was reported in Journal of Neuroscience. Reporting on 2 prior studies, Researchers looked at studies in which individuals were given a painful stimuli and underwent brain scanning and then were given a cream to apply to decrease pain. In both studies a placebo cream was used. In each of the studies, one group of individuals was told the cream was a placebo; in the other group, the participants were told the cream was an analgesic. For those who had a placebo effect, the researchers were able to "map" the areas of the brain that were active and responsive. It was discovered that the areas of emotion increased activity while the areas of processing pain decreased activity in placebo responders. The differences in activity were interpreted in placebo responders as an ability to "re-evaluate" the meaning of pain before it happened. The activity was most increased for expectation of pain, with the placebo responders able to change how the pain would be interpreted even before it happened.
The authors developed a "map" of the brain areas involved, and were able to predict which individuals would experience decreased pain. It is suggested that this "map" could be used to determine how much of a drug's effect is due to placebo response and also to identify individuals who are the most receptive to placebo therapy.


https://auth.telegraph.co.uk/sam-ui/...6-528c164bac6d

Placebos can work if your brain reinterprets pain, Jessica Hamzelou, New Scientist, January 15, 2011, p 15.


The above study is further investigation into the findings reported much earlier:
That placebo punch
Scientists are learning to harness the power of sham treatments -- without the trickery.
December 12, 2005
By Emily Singer


http://www.bri.ucla.edu/bri_weekly/news_051212.asp


"...For example, in two studies published in 2002, clinically depressed patients who responded to placebos showed dramatic changes in activity in the same areas of the brain that respond to antidepressants: the prefrontal cortex and the cingulate cortex. (The nature of these changes wasn't identical in those who took medicine versus placebo.)

Other imaging studies have shown that the prefrontal cortex is active during the placebo response. This is the same part of the brain that lights up when you try to make yourself feel better or worse — rather as if the placebo response is similar to your ability to cheer yourself up, to regulate your mood if you've had a bad day by telling yourself that things aren't so terrible.

"Things like pain don't just happen to you; your brain has to interpret the meaning and value to you," says Tor Wager, a psychologist at Columbia University in New York and author of some of the brain-scanning research. "Those circuits are partly under our control. The placebo is a way to [control] it beyond what we can do voluntarily."

Studies are also revealing the chemical changes that occur when placebos are given to people. A study... showed that sham injections of pain medicine blocked pain by activating the brain's natural painkillers, known as endorphins...

In a report by University of British Columbia researchers published in 2001, Parkinson's patients given a fake treatment (and who experienced improvements in tremors and other symptoms) exhibited a change similar to that seen with drugs used to treat the condition: an increase in the brain chemical dopamine.

Scientists don't know how placebos trigger the release of these substances. One theory holds that we learn to respond to placebos much like Pavlov's famous dogs learned to salivate at the sound of a bell signaling dinner.

Initially, our bodies may respond to a specific pain medication by releasing molecules — such as endorphins in the brain. But as we begin to associate the pill or doctor with that analgesic response, our brains may learn to respond to these factors rather than to the medication..."

[paula_w]

sounds like bedside manner is all important and there are many doctors with poor interaction. patients often leave an office feeling foolish rather than better.