Pain stimuli?

All I can say is this. Pain is two things: sensation and emotion. That's why doctors sometimes prescribe a drug like Xanax when the patient is about to undergo something painful, to deal with the emotional aspect. Two psychiatrists, Brown and Gerbarg, say a 10 or 20 min slow breathing exercise - 5 breaths a min - is good and 20 min twice a day is a therapy for anxiety. The exercise is inhale and exhale gently, 6 seconds each. This may be why mindfulness meditation helps with some kinds of pain. Mindfulness apps are very popular. A reviewer says his favorite is Mindful Life Project, which is easy to use and free. Other apps have monthly fees but they are still very popular.