Racial homogeneity in early childhood may affect brain

Kids who lived in orphanages have difficulty interpreting emotions on faces with foreign features

Seeing people of different races early in life may sculpt the developing brain, a new study suggests. Children who spent infancy in Chinese or Russian orphanages with little contact from outsiders had difficulty perceiving emotions on faces of people of unfamiliar races. These children also showed heightened brain responses to faces of unfamiliar races. 

“This new study is unique in that it for the first time tells us that early exposure to faces of different races is important,” says psychologist Kang Lee of the University of Toronto. “The lack of such exposure can have long-lasting effects.”

Although the results, published in the Aug. 14 Journal of Neuroscience, suggest that race shapes the brain during infancy, the study can’t say what such a brain change might mean, says study coauthor Eva Telzer of the University of Illinois at Urbana-Champaign. “Our findings do not say anything about children’s behavior in their daily life.”

Telzer and her colleagues studied one of the few populations that could help reveal these effects: orphans who the researchers believe lived amid a single race of people early in life. Most of these 36 children spent time in Russian or Chinese orphanages and were later adopted by American families of European descent. On average, the kids were adopted when they were 2 to 3 years old and were between 6 and 16 years old at the time of the study.

The children looked at a computer screen with a face showing a happy or angry expression. The kids then had to find that same expression on one of two new faces. Overall, the orphans performed just as well as 13 kids from Los Angeles, who presumably grew up seeing lots of people of other races. But the adopted kids were worse at matching emotions of faces of different races. The Asian kids were worse at matching expressions when the faces were European, and the European kids were worse at matching expressions of Asian faces.

Among the adopted kids, brain scans revealed a heightened level of activity in the amygdala while looking at faces of unfamiliar races. The amygdala is a brain region sensitive to surprising events and threats. The longer the children had spent in an orphanage, the team found, the greater the amygdala response.

Telzer thinks the children’s early racial environment tuned their developing brains. “Individuals are not born with biases to their own races,” she says. Instead, exposure to a particular racial group early in life primes the brain to become expert at recognizing faces of that racial group. This expertise may come at a cost, though, leaving the brain worse at handling faces of other races.

It’s well known that adverse environments—such as those found in some orphanages—can cause profound brain and behavioral deficits. So a hard orphanage life, and not necessarily a lack of racial diversity, could have influenced the results, says neuroscientist Charles Nelson of Harvard Medical School. And the scientists don’t know for sure the specifics of the orphans’ early environments. Volunteers of other races frequently travel to such orphanages, and the effects of seeing another race might take hold within minutes, Nelson says.

Laura Sanders is the neuroscience writer. She holds a Ph.D. in molecular biology from the University of Southern California.

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