Pain, considered to be subjective and without objective measurement, is being demystified by the use of brain imaging. Oral health researchers at King's College London Dental Institute have shown with a small study that pain can be seen in the brain.

According to the New Scientist, international science and technology site and magazine, Tara Renton, professor of oral surgery at King's College London Dental Institute, "has used an alternative way of analyzing fMRI [functional magnetic resonance imaging] scans called arterial spin labeling (ASL) to measure how much oxygenated blood is flowing through particular areas."

"The definition of pain is that it is subjective, and until now an objective measurement has remained elusive," said Morten Kringelbach, author and neuroscientist at the Oxford Univeristy, to the New Scientist.

Renton and fellow researchers analyzed the brains of 16 male dental patients who just had their wisdom teeth removed and the results showed specific areas of the brain fired up in direct relation to the pain described by said patients.

According to the New Scientist, Renton described the findings at King's College London on February 24 and said the ASL technique is the first objective measure of ongoing pain intensity.

Popsci, an online companion to Popular Scientist magazine, noted "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."