Bias bites back: racial prejudice may sap mental control.

Racial bigotry creates undeniable hardships for its targets. Such prejudice may cut two ways, though. A provocative new study suggests that intolerance undermines the mental resources of biased individuals when they interact with those whom they deem inferior.

White people who hold biased feelings toward blacks have to work to control their thoughts and behaviors during interracial encounters, say psychologist Jennifer A. Richeson of Dartmouth College in Hanover, N.H., and her coworkers. This social strategy depletes the limited pool of mental resources available for monitoring and using various types of information, the scientists propose.

Their investigation appears in the December Nature Neuroscience.

The results "suggest that harboring racial bias may be maladaptive to optimal cognitive functioning," Richeson's group concludes. Further research will be needed to establish how such laboratory findings relate to racial attitudes and behaviors in real-world situations, the team adds.

The researchers measured 14 male and 16 female college students, all of whom were white, for unconscious, or implicit, racial attitudes. First, participants were instructed to press a certain computer key when they saw a name paired with a word with positive connotations and to press another key when they saw a name paired with a negative word.

Volunteers generally were slower and less accurate at reacting to combinations of typically black names, such as Lakisha and Tyrone, with positive words, such as health and beauty, than with negative words, such as filth and ugly. One-third of the volunteers exhibited strong implicit racial bias, indicated by a pronounced difficulty in pairing black names with positive words and white names with negative words.

Participants then briefly conversed with either a black or a white experimenter.

Next, the students performed a task that required considerable mental control. They had to indicate the ink color in which color words such as red and green were printed. This task requires a person to override the impulse to read the word and instead report the ink color.

After talking with a black experimenter, volunteers who had scored high on implicit racial bias performed more poorly on the color-naming task than the other people did, the researchers say. No such pattern appeared after participants talked to the white experimenter.

Finally, when shown pictures of black faces, the people rated high on implicit racial bias showed more activity in brain areas involved in controlling thoughts and actions than the others did.

Richeson's investigation remains open to alternative interpretations, say psychologist William J. Gehring of the University of Michigan in Ann Arbor and his colleagues in a comment published with the new study.

For example, a high score in implicit racial bias may occur when a person has been exposed to lots of racially biased information, even if he or she doesn't endorse it, Gehring and his coworkers hold. Moreover, participants may have monitored their thoughts and actions during testing because they figured out that the experiment concerned race and feared that they had been tagged as racists.

Racial bias may have a broad influence on thinking processes, remarks psychologist Elizabeth A. Phelps of New York University. The new results need to be confirmed with different measures of bias and mental control, she says.