These include faster heartbeat, a quick look for an escape route, and the loosening of the bowels meant to lighten an animal for quick flight. Ploghaus said experiments on rats have shown a similar pattern, so the response is something that is probably common to most animals. It would make sense from an evolutionary point of view for a creature to respond quickly to pain and be prepared to avoid it. Ploghaus, who experimented on himself before subjecting any of his volunteers to his pain machine, said the heat was bad enough to be distressing but not enough to cause a burn. He hopes to use this research to help people with chronic pain.
Recent studies suggest that the fear of pain is much worse than the pain itself for such patients.
Patients will, for example, contort their bodies to avoid pain, thus causing even more. We want to screen drugs and psychotherapy for their ability to reduce the anticipation activation. If that activity is abolished, that shows us these treatments can be effective in reducing pain in chronic pain patients. The theory would explain why narcotics, antidepressants and antianxiolytics work for pain. None actually addresses the pain itself but rather make the patient less anxious about it.