As the first African-American president in United States history takes office, researchers have shown that it may be possible to scientifically reduce racial bias.

After being trained to distinguish between similar black male faces, Caucasian test subjects showed greater racial tolerance on a test designed to to measure unconscious bias.

The results are still preliminary, have yet to be replicated, and the real-world effects of reducing bias in a controlled laboratory setting are not clear. But for all those caveats, the findings add to a growing body of research suggesting that science can battle racism.

"Any time you can get people to treat people as individuals, you reduce the effect of stereotypes," said Brown University cognitive scientist Michael Tarr. "It won't solve racism, but it could have profound real-world effects."

Tarr's findings overlap with other results suggesting that the key to reducing racial bias — at least in a short-term, laboratory setting

— is exposure to people in personalized ways that challenge stereotypes. This is hardly a new notion: it's the essence of the contact hypothesis, formulated in the mid-20th century and the basis of integrated schooling.

But unlike carefully structured social mixing, with precisely controlled conditions of interdependence and equality, Tarr and others raise the possibility of a a lab-based shortcut to bias reduction.

Underpinning this research is the Implicit Association Test, used by psychologists to measure deep-rooted, often unconscious biases. During the test, subjects are measured on the time it takes to associate faces with positive or negative words. If, for example, someone more quickly associates negative words with minority rather than white faces, they're likely to have a bias — a bias that translates into a tendency to hire same-race workers, choose same-race partners, and find minority defendants guilty.

If the bias can be changed, perhaps the behavior will follow.

"The entire idea of neural plasticity is a new one. We didn't think that the brain was capable of change as we now know it to be," said Mahzarin Banaji, a Harvard University psychologist whose online Project Implicit has administered 4.5 million bias tests in the last decade. "The bias stuff we learn is heading in that direction, telling us that there is the ability to change."

"It's remarkable that our brain is so flexible that 10 hours of training will affect something that is the product of your whole life experience," said Tarr, who hopes his work will lead to race training for people working in potentially race-sensitive situations, such as police officers, social workers and immigration officials.

In a study published Tuesday in Public Library of Science ONE,

Tarr's team put 20 Caucasian college students through ten hours of face-identification training, testing their ability to discern previously-seen from unknown faces. Students with the largest improvements in face memory also showed significant improvements on a variation of the Implicit Association Test.

According to Banaji, a brief talk about working for women suffices to reduce gender bias. City University of New York psychologist Curtis Hardin showed that having black experimenters administer a test produced lower bias scores among white subjects.

In one of the few attempts to measure bias change and brain activity, Princeton University psychologist Susan Fiske simultaneously presented test subjects with pictures of black people and vegetables. When asked what the person in the picture liked to eat, activity in the amygdala — a brain region that modulates fear — subsided.

"Amygdala activation goes away as soon as you start to think of people as individuals," said Fiske.

These results are promising, but it's too soon to say whether they're long-lasting, or will translate to real-world improvements in behavior.

"Our biggest concern is that if we have participants come into a lab and do some exercises, then the context is so specific that it may only work if they see an African-American in a lab," said Bertram Gawronski, a University of Western Ontario cognitive scientist. "It's really important that it's done in different contexts, and that people are repeatedly bombarded with counter-attitudinal information."

For at least the next four years, however, the United States will collectively undergo a real-world experiment in stereotype defiance.

"The first black president — that's going to have a huge effect on things that come to mind," said Ohio State University psychologist Richard Petty. "Instead of just negative associations, there will be all sorts of positive associations."

Let's just hope they last.

Citation: "Perceptual Other-Race Training Reduces Implicit Racial Bias." By Sophie Lebrecht, Lara J. Pierce, Michael J. Tarr and James W. Tanaka. Public Library of Science ONE, Jan. 21, 2009.

Image: VizCogLab/University of Victoria

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