I've noticed that some people are bothered by pain more than others. I seem to have a pretty high tolerance for pain. Is that just personality? A genetic trait or what?

Scientists studying pain and especially chronic pain are learning more and more all the time. It appears that people in chronic pain do have lower pain thresholds and higher pain sensitivities. But whether this was present before the injury or occurs as a result of trauma remains unknown.

New studies of brain patterns are helping us understand pain mechanisms. It seems that there is an actual brain network in charge of acute pain perception. Functional magnetic resonance imaging studies (fMRIs) are helping map out brain activity in people with acute and chronic pain. The results are compared to responses from normal, healthy adults without pain.

The role of chemicals and hormones in pain perception is showing a clear biologic basis for some aspects of pain. Some experts think that personality is a combination of biologic, chemical, and genetic traits. If this is true, then you are right in guessing both play a major role in how pain is perceived and handled.