An observer feels more empathy for someone in pain when that person is in the same social group, according to a functional MRI (fMRI) study in the July 1 issue of the Journal of Neuroscience. The study shows that perceiving others in pain activates a part of the brain associated with empathy and emotion more if the observer and the observed are the same race.
According to the researchers, the findings may show that unconscious prejudices against outside groups exist at a basic level.
"Our findings have significant implications for understanding real-life social behaviors and social interactions," said study co-author Shihui Han, PhD, from the department of psychology at the Peking University in Beijing, China.
Recent brain imaging studies show that feeling empathy for others in pain stimulates a brain area called the anterior cingulate cortex. Building on these results, the study authors tested the theory that these empathic feelings increase for members of the same social group. In this case, the researchers chose race as the social group, although the same effect may occur with other groups.
Using fMRI, the researchers scanned brains in one Caucasian group and one Chinese group. The authors monitored participants as they viewed video clips that simulated either a painful needle prick or a non-painful cotton swab touch to a Caucasian or Chinese face.
Han and colleagues found that when painful simulations were applied to individuals of the same race as the observers, the empathic neural responses increased; however, responses increased to a lesser extent when participants viewed the faces of the other group. The authors concluded that their "findings uncover neural mechanisms of an empathic bias toward racial in-group members."
Martha Farah, PhD, a unaffiliated cognitive neuroscientist and neuroethicist at the University of Pennsylvania in Philadelphia, said learning how empathic responses influence behavior in many different situations is interesting both practically and theoretically.
"This is a fascinating study of a phenomenon with important social implications for everything from medical care to charitable giving," she said.
However, the finding raises as many questions as it answers, according to Farah.
"For example, is it racial identity per se that determines the brain's empathic response, or some more general measure of similarity between self and other?" she said. "What personal characteristics or life experiences influence the disparity in empathic response toward in-group and out-group members?"
The research was supported by the National Natural Science Foundation of China.