One way to alleviate the pain of banging your shin while on a hike is to encounter a grizzly bear—a well-known phenomenon called stress-induced analgesia. Now, researchers have elucidated a key mechanism by which the stress hormone noradrenaline—which floods the bloodstream during grizzly encounters and other stressful events—affects the brain’s pain-processing pathway to produce such analgesia.Pankaj Sah and colleagues published their findings in the December 6, 2007, issue of the journal Neuron, published by Cell Press.
