Going by the findings of a brain-imaging study, published in the journal Pain, some people experience genuine physical reactions to the injuries of others - with almost one in three people actually feeling "functional" pain on seeing the physical discomfort of others.

The findings, based on functional magnetic resonance imaging (fMRI), revealed that people who say they feel vicarious pain actually undergo heightened activity in pain-sensing regions of their brain whenever they see someone else being hurt.

For the study, Dr Stuart Derbyshire, a psychologist at the University of Birmingham, UK, and colleagues observed the reactions of 123 university students who were made to watch video clips and photographs which showed patients and sportsperson getting hurt.

While all the students said that they experienced an "emotional reaction," that of sadness, disgust or fear, for at least one of the images or videos; one-third of them claimed that they felt real pain in the same part of the body as the injured person.

The researchers then used fMRI to scan the brains of 10 of these 'responders' and 10 'non-responders' - those who felt no pain. It was found that the responders showed increased activity in pain-related brain regions, vis-à-vis the non-responders.

Researchers said that the findings, which explain why some people are more compassionate of the suffering of others, would likely help in understanding, and probably even treating, the cases of the thus-far inexplicable "functional" pain.