Scientists in the United Kingdom have observed increased brain responses to faces of people of a different ethnicity. The new study, which was published in the journal Psychological Medicine, demonstrated for the first time that amygdala reactivity to white faces was increased in black ethnic minorities.

“Research from around the world has shown that being a member of a minority group is associated with an increased risk of some mental illnesses but the reason why is not known. We wanted to know if this could involve differences in how the brain responds to people from minority or majority groups,” explained study author Oliver Howes, a professor of molecular psychiatry at Imperial College London.

In the study, 20 black individuals and 20 white individuals viewed photos of black and white male faces while their brain activity was observed with a MRI.

Howes and his colleagues were particularly interested in the amygdala, a brain structure important for the regulation of fear and stress.

The researchers found an increased amygdala activation in response to viewing white faces among the black participants, and an increased activation to black faces among the white participants.

“We found that the brain’s response to seeing people from a different group was increased in an area involved in emotional processing, but this was less marked in people who lived in areas where populations were more integrated,” Howes explained to PsyPost.

But it is unclear whether living in a more ethnically diverse environment leads to reduced neural responses to faces of a different ethnicity — or whether people who already have reduced neural responses are more likely to move into ethnically diverse areas.

“We were not able to test the direction of the links,” Howes said. “The next step would be to test if moving to a more integrated area led to a reduction in the brain’s response to seeing people from different groups.”

“This study suggests that our social environments and psychological responses to it are linked to how the brain processes information.”

The study, “Amygdala reactivity in ethnic minorities and its relationship to the social environment: an fMRI study“, was co-authored by Robert McCutcheon, Michael A. P. Bloomfield, Tarik Dahoun, Marina Quinlan, Sylvia Terbeck, and Mitul Mehta.