The seemingly subjective nature of pain always proves problematic for doctors, who have to use a woefully imprecise chart to gauge a patient's suffering. But by using a new interpretation of fMRI scans, doctors at King's College London have found a way to measure the brain's pain response in a quantitative way. Aside from providing a more precise tool for doctors, this technology may also enable doctors to measure pain in people with locked-in syndrome, people in vegetative states, pre-verbal children, animals, and fetuses.
The doctors monitored the brains of 16 men after they had their wisdom teeth removed. In the study, the intensity of brain activity in certain regions correlated directly with the intensity of pain reported by the men. In other experiments, the researchers pricked the fingers of volunteers with a needle, or had them touch a hot plate, while measuring brain activity.
However, some critics believe that the study's emphasis on short-term, localized agony oversimplifies the concept of pain to the point of uselessness. Since pain involves the complex interplay of emotions and memory -- for instance, the phantom limb pain of amputees -- fMRI scans for pain may not provide any more guidance to doctors than the smiley face chart already in use.
But the applications of this technology for fields beyond medicine, such as animal rights, may prove more transformative than any medical use. Using the fMRI on animals could quantify the pain levels of veterinary and slaughter procedures, potentially changing the way we both heal and kill animals.
And then there's the possibility of finally answering the question of whether or not fetuses feel pain. If this technology can accurately answer that question, either a positive or a negative result is sure to spark a wave of controversy and political action.