Rather than try and paraphrase the science, I'm sure Tom won't mind me quoting him directly (and nicking his diagram - sorry!):
"It turns out that the right ventrolateral prefrontal cortex (RVLPFC) - shown in the little graphic above - is the bit that lights up in the Catholics who felt less pain as a result of their Madonna-induced rapture. Because the RVLPFC is known to play a role in the reassessment of the emotional evaluation of experiences, the researchers propose that the religious state leads to a reassessment of the pain, giving it new more positive meaning and so making it less, well, painful.As a non-scientist, I smelled Templeton cash, silly-sounding methods (giving 12 Catholics and 12 atheists electric shocks while looking at paintings) and a quote from the Bishop of Durham claiming the research as a justification for his own religion, and jumped to conclusions. But here we have the truth -the experiment wasn't that dodgy and, as far as pain's concerned, religious faith can be a handy placebo. But so can many other things.
"No doubt that's true. But before any religious believers ... get too excited about the wonders of religious belief, it should be pointed out that the RVLPFC is in fact the bit of the brain that drives your response to any kind of placebo - including, for example, your common-or-garden sugar pills ... In other words, as far as pain relief goes, you can substitute the mystery of the trinity with a good old-fashioned sugar pill and some kind words from the GP. They work the same way."