Broken heart hurts as much as physical pain

"These results give new meaning to the idea that social rejection 'hurts'," said University of Michigan social psychologist Ethan Kross, lead author of the article.

"On the surface, spilling a hot cup of coffee on yourself and thinking about how rejected you feel when you look at the picture of a person that you recently experienced an unwanted break-up with may seem to elicit very different types of pain.

But this research shows that they may be even more similar than initially thought."

The current study is the first known to establish that there is neural overlap between both of these experiences in brain regions that become active when people experience painful sensations in their body.

These regions are the secondary somatosensory cortex and the dorsal posterior insula.

For the study, the researchers recruited 40 people who experienced an unwanted romantic break-up within the past six months, and who indicated that thinking about their break-up experience led them to feel intensely rejected. Each participant completed two tasks in the study---one related to their feelings of rejection and the other to sensations of physical pain.

During the rejection task, participants viewed either a photo of their ex-partner and thought about how they felt during their break-up experience or they viewed a photo of a friend and thought about a recent positive experience they had with that person. During the physical pain task, a thermal stimulation device was attached to participants left forearm. On some trials the probe delivered a painful but tolerable stimulation akin to holding a very hot cup of coffee. On other trials it delivered non-painful, warm stimulation.

Participants performed all tasks while undergoing functional Magnetic Resonance Imaging (fMRI) scans. The researchers conducted a series of analyses of the fMRI scans, focusing on the whole brain and on various regions of interest identified in earlier studies of physical pain. They also compared the study''s results to a database of more than 500 previous fMRI studies of brain responses to physical pain, emotion, working memory, attention switching, long-term memory and interference resolution.