Have there been any studies comparing the brains of people who derive pleasure from pain vs people who don’t? I wonder if this could be related? Some people see

Have there been any studies comparing the brains of people who derive pleasure from pain vs people who don’t? I wonder if this could be related? Some people seem to have “trained” their brains not to recognize pain signals as unpleasant. Or (because I imagine they still feel pain) maybe they can even decide when and which pain signals are pleasant vs unpleasant? I wonder if people who enjoy BDSM are any more or less likely to suffer from chronic pain than the rest of the population.