The Associated Press is running a story covering the positive effects of positive patient expectations. Among the findings at various universities:
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.
Italy’s [Dr. Fabrizio] 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.
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.
The article repeatedly tries to specify that the placebo effects observed weren’t just psychological, but also physical. However, there is a physical electro-chemical embodiment of all psychological activity. The distinction disregards links between neural activity and it’s body-wide effects. However, all-in-all, it highlights the importance of patient perception on mediating the known effects of a drug or technology.