THE MIND'S POWER AND THE PLACEBOAn article in the New Scientist caught my attention. It listed 13 things that do not make sense, and the first was the placebo effect. The article described a research experiment at the Torino Medical School in Italy in which several times a day, for up to five days, pain was induced in 229 volunteers. The pain was controlled with morphine for the second and third day of the experiment when the morphine was replaced in some groups with a saline solution. The saline solution also reduced the pain! In some of the groups the experimenter used naloxone on the fourth day, a drug that blocks the effects of morphine. The researchers concluded that the pain relieving power of the placebo saline solution "could be blocked completely by naloxone." In my view our body is like a chemical factory. For the placebo the body could be producing a morphine-like chemical. The question is "who" chooses which chemicals our bodies will produce after we have been exposed to conditioning, cognitive, and motivational factors such as expectations? We know that placebos can be as powerful as the best modern medicine. Studies show that between 30 and 40 percent of patients report feeling better after taking dummy pills for conditions ranging from depression, to high blood pressure, to Parkinson's. What fascinated me most was that placebo shave been shown to work for problems that were addressed by surgical intervention. In the 1940's and 1950's, thousands of patients underwent a painful procedure known as internal mammary ligation. The procedure involved cutting into the chest and tying knots in some of the arteries supplying blood to the heart. Most were happy because the procedure appeared to work. Three-quarters of all patients who underwent the operation improved. Then in the late 1950's a research experiment using a sham operation was tried. It involved cutting into the chest but not tying knots in any arteries. The results of the sham operation were just as impressive as the real procedure. Doctors have now abandoned the use of internal mammary ligation operations. However, the question of how mere belief could be so effective in reducing chest pain was not addressed! In 2002 the New England Journal of Medicine reported on sham surgery for osteoarthritis of the knee. The research was a very well designed study of 165 patients over two years. Doctors at a Houston VA Hospital performed arthoscopic knee surgery on one group of patients with arthritis, scraping and rinsing their knee joints. On another group, the doctors made small cuts in the patients' knees to mimic the incisions of a real operation and then bandaged them up. The pain relief reported by the two groups was identical. Approximately 650,000 arthoscopic procedures for knee osteoarthritis are performed yearly in the United States at a total cost of about $3.25 billion. New insight into how the brain works and hence how the placebo works is resulting from functional imaging techniques. Functional imaging depicts what the brain is doing over a certain period of time ranging from seconds to minutes. These techniques are based on the principle that brain activity leads to changes in blood flow, electrical discharges, and magnetic fields. Placebo experiments with Parkinson's disease measured the activity of neurons in the patients' brains. When a saline placebo was administered, individual neurons in a common target area that are used for surgical attempts to relieve Parkinson's symptoms began to fire less often. There were also fewer "bursts" of firing, which is a feature associated with Parkinson's disease. Since the neuron activity decreased at the same time as the symptoms improved, it was clear that the placebo was doing something -- the mind was affecting the body! This and other brain research has shown that people have the capacity to affect the electrochemical dynamics of their brains by changing the nature of their mind process. Change your thoughts and you change your brain; change your brain and you change your feelings. The placebo represents an unconscious positive change due to a mental belief. The question is whether we can produce such positive changes with conscious intent. What are the limits? We can not be sure and the topic is very controversial. However, we know that: Without "belief" the placebo will not work; and likewise without "belief" conscious intent will not work.
William C. Gough, FMBR Chairman of the Board;
MARCH
, 2007
REFERENCES:
Amanzio, Martina and Fabrizio Benedetti, "Neuropharmacological Dissection of Placebo Analgesia: Expectation-Activated Opioid Systems versus Conditioning-Activated Specific Subsystems," The Journal of Neuroscience, January 1, 1999, 19(1): pp.484-494. Updated Mar 8, 2007. |