Naomi L. Eisenberger of the University of California at Los Angeles and her colleagues recruited 13 college students to play a virtual game of catch while their brains were scanned using functional magnetic resonance imaging (fMRI). At first, the students were told they could only observe the game. Their computer-generated playmates, which the subjects believed were controlled by unseen people, then began throwing to them. But after about 40 throws, the other players began ignoring the subject with no explanation. The researchers found that this exclusion caused activity in a region of the brain known as the anterior cingulate cortex, or ACC. In addition, students who reported feeling the most distress from being snubbed showed the greatest activity in this brain region, which is also involved in pain processing.
The authors note that although similar brain processes are involved in both rejection and pain, differences between the two experiences remain. Still, they conclude, better understanding the underlying commonalities that physical and social pain share may help explain "why it 'hurts' to lose someone we love."