They release a bath of chemicals that induces the nerves to carry the pain message to the brain. Even with general anesthesia, a patient's central nervous system remains alert and ushers pain messages back and forth from the nociceptor, through the nerves, into the spinal cord, and on to the brain. The brain responds by washing the spinal cord with glutamate, a chemical that rewires the central nervous system and creates a physical memory of pain. But in financial terms it certainly will be worthwhile. Approximately 25 million Americans suffer from acute pain due to injuries or surgery.
Laboratory studies show a clear difference in pain tolerance levels between men and women.
When healthy men and women are subjected to heat and other types of pain tests, women almost always report feeling discomfort first. The laboratory studies show rather convincingly that women have a lower pain threshold and pain tolerance than men. That has been fairly consistently shown in the experimental studies that have been done. To measure the differences in pain tolerance between men and women, Fillingim uses something called effective size, which compares the differences between the groups to the differences within each group. On a scale of small, moderate, and large, the pain tolerance difference between men and women is considered moderate.