Researchers at Stanford University used functional MRI to detect when people were experiencing pain by detecting changing blood flow patterns in the brain. Because pain, almost by definition, has always been a subjective phenomenon, judging its true nature is difficult as some people are more tolerant of it than others.
The scientists hope a more objective tool may one day be developed, but they caution that the latest research is at a very early stage of this endeavor.
Researchers took eight subjects, and put them in the brain-scanning machine. A heat probe was then applied to their forearms, causing moderate pain. The brain patterns both with and without pain were then recorded and interpreted by advanced computer algorithms to create a model of what pain looks like. The process was repeated with a second group of eight subjects.
The idea was to train a linear support vector machine — a computer algorithm invented in 1995 — on one set of individuals, and then use that computer model to accurately classify pain in a completely new set of individuals.
The computer was then asked to consider the brain scans of eight new subjects and determine whether they had thermal pain.
Press release: Does that hurt? Objective way to measure pain being developed at Stanford
Full article in PLoS ONE: Towards a Physiology-Based Measure of Pain: Patterns of Human Brain Activity Distinguish Painful from Non-Painful Thermal Stimulation
Image: Stanford Office of Communication & Public Affairs