The brain draws on a range of pain-fighting options when people receive sham treatments for pain, a new brain-imaging study suggests.
People who experienced pain relief after receiving fake acupuncture treatments displayed pronounced activity in certain brain areas, says a team led by neuroscientist Jian Kong of Massachusetts General Hospital in Charlestown. This pattern of brain activity differed from that reported in 2004 by another team, directed by neuroscientist Tor D. Wager of Columbia University.
In that work, a placebo cream applied to the skin diminished pain. In both experiments, the researchers induced volunteers' pain by applying heat to the forearm.
"There may be multiple brain mechanisms underlying placebo [pain relief]," Kong says. He and his colleagues describe their findings in the Jan. 11 Journal of Neuroscience.