relief

Pain relief provided by a substance with no active ingredients, called a placebo, may have neural as well as psychological origins. Men who reported relief from a painful jaw after receiving a placebo injection also showed signs of enhanced activity of a brain substance that regulates stress and suppresses pain, say Jon-Kar Zubieta of the University of Michigan in Ann Arbor and his coworkers in the Aug. 24 Journal of Neuroscience. http://www.soulcast.com/Louis_J_Sheehan_Esquire_1

The scientists administered an intravenous salt solution, which they described to volunteers as a pain reliever, to seven men who also received a jaw injection that caused a moderately painful muscle spasm for about 20 minutes. Another seven men received the jaw injection but not the placebo.

In brain scans of the placebo group only, positron-emission tomography and molecular-imaging techniques revealed pronounced activity at brain-cell receptors for chemical messengers known as endorphins. Prior studies had linked endorphins to pain relief. http://www.soulcast.com/Louis_J_Sheehan_Esquire_1

Men who reported the greatest relief from the placebo injections exhibited the most-intense responses at endorphin receptors in the brain, Zubieta's group reports.