In a set of recent studies, researchers were able to determine whether individual subjects were feeling pain — simply by observing scans of their brain activity. As detailed in The New England Journal of Medicine, the studies involved 114 different individuals, who had their brains scanned using functional magnetic resonance imaging. During the scans, they were exposed to heat of varying degrees while being asked to rate their pain level on a scale of one to nine. The researchers then looked at the resulting brain scans, and discovered a common pattern of activity.

By keying off this signature, they were able to differentiate between which subjects were simply feeling heat and which ones were feeling pain from the exposure. In the first study, the technique was successful 94 percent of the time, while the second study yielded a 93 percent success rate. The intensity of the signature pattern also decreased when pain medication was administered to subjects. In a third study, some subjects that had recently gone through relationship break-ups were shown pictures of their former partners to add emotional pain to the mix. In that case, the signature was able to determine which subjects were feeling pain 85 percent of the time, and was able to determine which were simply feeling emotional distress 73 percent of the time.

The study has enormous potential benefits in both pain management and helping treat those who may be unable to express whether they're feeling pain for one reason or another. It could also be of use for doctors that are trying to objectively determine whether patients are in pain, whether they say they are or not. That said, further research will need to be done. The researchers note that different kinds of pain felt in other parts of the body could result in their own distinct pain signatures, and the studies as conducted did not address chronic pain that individuals may have to deal with over the course of a lifetime due to illness or other maladies.