Music has charms?

From a May 2006 Slate article by Dr. Sydney Spiesel: "The ideal analgesic would diminish pain perception without increasing the risk of harm to patients. How about … music? A recent study, led by Dr. M.S. Cepeda of Javieriana University in Bogota, Colombia, and Tufts-New England Medical Center, put together the results of 51 different papers (involving more than 3,500 patients) that evaluated the value of music for pain relief. The studies examined the effect of music on chronic or cancer pain, acute pain following surgery, labor pain, and the pain produced by medical or experimental procedures. The amelioration of pain was measured in two ways, one subjective and the other objective. Did patients hearing music report a substantial decrease in the pain they felt? And did they require less opiate medication than similar patients who didn't hear music? The results Cepeda found were positive but not powerful. In most of the studies, listening to music modestly decreased patients' reported perception of pain (no matter what its cause) or was associated with somewhat less need for opiate medication. But the differences weren't strong enough to make clear whether music is clinically useful. Perhaps the most interesting results came from the studies in which patients were allowed pick the music they wanted to listen to. Contrary to what one might expect, freedom to choose pretty much killed the benefit for pain relief. Which leaves another question crying out to be answered: Would people feel more relief if they were made to listen to music they hate? We could try this out by playing, say, Metallica for a classicist in a dental chair, or a late Beethoven quartet for a biker about to get a tattoo."

I find the last part of this, in particular, fascinating. Why the counterintuitive, *better* result with music not of the patients' choosing? Did it function as a counterirritant? Or is there some some of "novelty effect" at work? I have noticed that listening to unfamiliar songs on the car radio often seems to kick-start my creative process where listening to a favorite CD will not. As Dr. Spiesel implies, it would be interesting to know if the selections played in the study were entirely unfamiliar to the patients, as opposed to known but not preferred.