A unique new study done at Dartmouth sheds light on the mental energy exhausted in interracial interactions.
A team of professors and Ph.D. students used functional MRI imaging to study racial bias, exposing Caucasian subjects to African-American individuals and measuring their brain activity. The research showed that the mental effort of suppressing racial bias actually inhibited the white subjects' ability to perform cognitive tasks.
Jennifer Richeson is an assistant professor of psychological and brain sciences and was the lead author of the paper published Nov. 16 in "Nature Neuroscience." She told the College's Office of Public Affairs that she was "surprised to find that brain activity in response to faces of black individuals predicted how research participants performed on cognitive tasks after actual interracial interactions."
The study measured a group of 30 white individuals for racial bias using a computer-based test. The test determined the subjects' ability to associate black or white individuals with positive or negative characteristics. Bias was assessed by measuring how much longer it took the subjects to associate white people with negative attributes and black people with positive attributes.
The participants then completed other tasks, like interacting with or looking at pictures of black or white individuals, and their responses were measured by the research team. The results were striking, Richeson said.
"We found that white people with higher scores on the racial bias measure experienced greater neural activity in response to the photographs of black males [in] an area in the front of the brain that has been linked to the control of thoughts and behaviors," Richeson said.
The research ultimately found that even unintentional racial bias causes a mental exhaustion, similar to muscle fatigue, that makes cognitive tasks more difficult. The team's summary states that harboring racial bias in an increasingly diverse society may be bad for one's cognitive performance.