If you've ever thought that you literally feel other people's pain, you may be right. A brain-imaging study suggests that some people have true physical reactions to others' injuries.
Using an imaging technique called functional MRI, UK researchers found evidence that people who say they feel vicarious pain do, in fact, have heightened activity in pain-sensing brain regions upon witnessing another person being hurt.
The findings, published in the journal Pain, could have implications for understanding, and possibly treating, cases of unexplained "functional" pain.
For the study, the researchers first had 108 college students view several images of painful situations -- including athletes suffering sports injuries and patients receiving an injection. Close to one-third of the students said that, for at least one image, they not only had an emotional reaction, but also fleetingly felt pain in the same site as the injury in the image.
The researchers then took functional MRI scans of 10 of these "responders," along with 10 "non-responders" who reported no pain while viewing the images.
Functional MRI charts changes in brain blood flow, allowing researchers to see which brain areas become more active in response to a particular stimulus. Here, the researchers scanned participants' brains as they viewed either images of people in pain, images that were emotional but not painful, or neutral images.
The investigators found that while viewing the painful images, both responders and non-responders showed activity in the emotional centers of the brain. But responders showed greater activity in pain-related brain regions compared with non-responders, and as compared with their own brain responses to the emotional images.