Prometheus 6

How Harvard students perceive rednecks: The neural basis for prejudice
From Mind Matters

Stephen L. Macknik

Laboratory of Behavioral Neurophysiology
Barrow Neurological Institute
Phoenix, Arizona

The source of many of the world's woes might be tracked to a specific brain area responsible for identifying people that are not of our ilk. If so, a study on the neural bases of prejudice and its modulation (read abstract or download the pdf), by Jason Mitchell and Mahzarin R. Banaji, of Harvard University, and C Neil Macrae, at the University of Aberdeen in Scotland, published in Neuron in May 2006, could be as important to the burgeoning field of social cognitive neuroscience as Martin Luther King Jr.'s "I have a dream" speech was to the American civil rights movement.

Like-minded

How does the brain differentiate those who are similar to us from those who are different? Does it analyze differences in skin color, language, religion, height, eye color, foot size? Does it discriminate cat versus dog lovers, Pepsi versus Coke drinkers, Shiite versus Sunni, Crips versus Bloods?

In a way, the brain does all this and more by simply distinguishing those who don't meet various definitions of who we are. Specifically, a forebrain area called the dorsal medial prefrontal cortex (mPFC) appears to predict the behavior of members of outgroups by employing prejudices about their presumed background -- assumptions we make, in other words, based on what groups their various traits and contexts seem to put them in or out of. In this sense, outsiders, or those in outgroups, include humans of dissimilar cultural or ethnic identities or any other perceived stereotyped dissimilarity from your own self-identified groups, as well as non-human agents such as cartoons and animals and even inanimate moving objects. We distinguish otherness by all sorts of indicators, from the seemingly obviously, like sex or race, to the more obviously cultural, such as whether a person is wearing, say, a Yankees cap, a Dodgers cap, or a tee-shirt that says Baseball Sucks.

The focus of the paper under review here focuses less on the cues than on the brain areas that respond to them. The authors detailed the function of a particularly important brain area while studying the neural correlates of "mentalizing." Mentalizing is the ability to predict how other people will behave in a given situation. It combines the powers of theory of mind (our ideas about what other people know and do not know) with the presumptions that we hold about people with dissimilar backgrounds. Some researchers believe that mentalizing is a function of the brain's mirror neuron system, allowing us to predict the behavior of others by simulating how other people may feel in a given situation.