CAMBRIDGE, Mass. -- Psychologists have found that the amygdala, a subcortical region of the brain involved in emotional responses, is associated with a measure of unconscious race bias, especially when responding to faces presented subliminally. Their research also indicates that other higher areas of the brain that are involved in deliberative thought processes can moderate the amygdala activity. Their experiment, which suggests that the conscious brain can compensate for unconscious prejudices, assessed participants' reaction to faces displayed either subliminally, for three-hundredths of a second, or supraliminally, for slightly more than half a second.
The study, by authors at Harvard University, Yale University, and the University of Toronto, was conducted at Yale using functional magnetic resonance imaging (fMRI), and is reported in the December issue of the journal Psychological Science.
"Physical properties that make up a person cannot be disregarded in face-to-face interactions, and the imprint of culture is what's reflected in the response to a 30-millisecond subliminal exposure," says co-author Mahzarin R. Banaji, Richard Clarke Cabot Professor of Social Ethics in the Department of Psychology in Harvard's Faculty of Arts and Sciences and Carol K. Pforzheimer Professor at Harvard's Radcliffe Institute for Advanced Study. "However, seeing the face consciously, for as little as a half second, allows a more reasoned response to the face in view."
The researchers performed fMRIs on 13 white participants. During the scans, participants viewed a series of faces - some of which could be consciously seen and some of which were presented so quickly that participants did not report seeing them. The researchers found that for the ultra-brief subliminal images, amygdala activity was greater in response to black faces than to white faces, suggesting that at least initially, black faces provoked a stronger emotional reaction than white faces. Page: 1 2 3 Related medicine news :1
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