June 28, 2005
by Orrin Schonfeld
Los Angeles-- Is it possible to have racial biases without even knowing it? Research on a primitive part of the brain suggests that it is. But a new experiment shows that simply putting biases into words may help us overcome them.
MRI scanners let neuroscientist Matthew Lieberman peer deep inside the brain to observe a region called the amygdala. It reacts to perceived threats, and studies have shown it may be involved in expressing unconscious racial biases.
"White Americans tend to show greater activity in a part of the brain called the amygdala when they’re looking at African American faces, compared to when they’re looking at Caucasian American faces," said Lieberman.
But the amygdala also responds to unfamiliar things in the environment, so researchers couldn’t be sure if this increased activity actually showed racial biases.
To find out, Lieberman scanned the amygdalas of African American subjects while they looked at African American faces. It turned out their response was the same as that of Caucasian subjects. "African Americans, unlike Caucasian Americans, are not likely to find other African American faces to be novel. It may have something more to do with the sort of learned associations."
The results, published in the journal Nature Neuroscience, suggest that amygdala activity does reveal subtle racial biases.
But Lieberman also found that when subjects from both races matched words to the images, the amygdala response to African American faces disappeared. "Putting our reactions at least into words in our own minds may be something that allows us to sort of engage in interactions that are more free of bias."
Lieberman stresses that these findings are only a first step in exploring the biology of racial biases.
Columbia University Neuroscientist Joy Hirsch agrees. "This study actually raised more questions at the end than they provide answers." She adds that racial bias may be too complex-- and personal-- for neuroscience to fully explain.
Future experiments on the amygdala may include people of other ethnicities.