A placebo is a tablet or a liquid with no medical qualities that physicians will give to calm the anxieties of patients who insist upon receiving drugs when none are deemed necessary. In other instances, pharmacologists who wish to test the effects of a new drug may give placebos to a control group and the real drug to another as a method of gaining a more accurate determination of the effectiveness of the drug under development.
On April 30, 2002, researchers at the University of Texas Health Science Center announced their findings that depressed people given a placebo exhibited changes in their brain that were nearly identical to those produced by a popular antidepressant. The leader of the research group, Dr. Helen Mayberg, University of Toronto Professor of Neurology and Psychiatry, said that patients who responded to the placebo and those who responded to the actual antidepressant showed similar metabolic changes in cortical (thinking) and limbic-paralimbic (emotional) regions of their brains. Of the 15 men who completed the study at the health center, eight had experienced a noticeable improvement in their symptoms. Four had been administered the drug, and four had been given a placebo.
Volunteers in a pain relief experiment conducted by the Neurophysiology Research Group in Stockholm, Sweden, also demonstrated that both placebos and powerful painkilling drugs activate the same areas of the brain. Brain scans indicated that both the true painkilling drug and a salt water placebo activated the same two areas of the brain—the rostral anterior cingular cortex and the brain stem.
Ingvar said that perhaps the most unexpected finding of the experiment was that those individuals who responded most strongly to the true drug also responded most positively to the placebo injection. Such a discovery may indicate that certain people have "stronger pathways in the brain for pain relief." According to the researchers, pain relief may often literally be a case of mind over matter.
Czerner, Thomas B.What Makes You Tick? The Brain in Plain English. New York: John Wiley & Sons, 2001.
Fox, Maggie. "Placebo, Drugs Both Activate Brain in Pain Relief."Yahoo! News/Reuters, February 7, 2002. [Online] http://story.news.yahoo.com/news?tmpl=story&u/nm/20020207/sc_nm/science_pain_dc_1.
Moore, Oliver. "Placebo Can Fool the Brain, Study Finds."Globe and Mail, April 30, 2002. [Online] http://www.globeandmail.com/servlet/RTGAMArticleHTMLTemplate?tf=tgam/realtime/ful.
Shapiro, Arthur K., and Elaine Shapiro.The Powerful Placebo: From Ancient Priest to Modern Physician. Baltimore, Md.: Johns Hopkins University Press, 2001.