The Placebo effect has long been recognized as a factor in determining the efficacy of various medical intervention therapies. A newly published study, "Direct Evidence for Spinal Cord Involvement in Placebo Analgesia"*, by Eippert, Finsterbusch, Bingel and Buchel of the Departments of Systems Neuroscience and Neurology, University Medical Center Hamburg-Eppendof in Germany finds quantitative-observable physical evidence of the effects of suggestion.
Albeit, the study involves only 15 healthy male volunteers with a mean age of 25 years and a range of 21 to 30 years. A series of systematic and highly suggestive tools were used to trick the volunteers into believing they had been administered a potent analgesic during the manipulation and test phase of the experiment. The suggestions involved the use of color coding for the fake creams and verbal suggestions relating to the anticipation of pain including the introduction of extreme heat on the forearm of the volunteers.
An MRI was utilized to scan the dorsal horn region of the spinal cord during the test phase of the experiment. In analyzing the findings, the Eippert team of scientists caution the size of experimental group may have influenced the study. However, the physical manifestations of the deceptive suggestions including "fake" creams, packaging and verbal suggestions could be detected on the fMRI as reducing pain. The scientists agree, the so-called placebo effect or psychological effect opens up numerous paths of study in reducing chronic pain and related treatments.
*More information: "Direct Evidence for Spinal Cord Involvement in Placebo Analgesia", Science 16 October 2009, Vol. 326. no. 5951, p. 404, DOI: 10.1126/science.1180142
• See also Supporting online material (PDF)
© 2009 PhysOrg.com
Explore further: Scientists discover brain's anti-distraction system