Is America's red-blue divide based on voters' physiology? A new paper in the journal Science, titled "Political Attitudes Are Predicted by Physiological Traits," explores the link.

Rice University's John Alford, associate professor of political science, co-authored the paper in the Sept. 19 issue of Science.

Alford and his colleagues studied a group of 46 adult participants with strong political beliefs. Those individuals with "measurably lower physical sensitivities to sudden noises and threatening visual images were more likely to support foreign aid, liberal immigration policies, pacifism and gun control, whereas individuals displaying measurably higher physiological reactions to those same stimuli were more likely to favor defense spending, capital punishment, patriotism and the Iraq War," the authors wrote.

Participants were chosen randomly over the phone in Lincoln, Neb. Those expressing strong political views -- regardless of their content -- were asked to fill out a questionnaire on their political beliefs, personality traits and demographic characteristics.

In a later session, they were attached to physiological measuring equipment and shown three threatening images (a very large spider on the face of a frightened person, a dazed individual with a bloody face and an open wound with maggots in it) interspersed among a sequence of 33 images. Similarly, participants also viewed three nonthreatening images (a bunny, a bowl of fruit and a happy child) placed within a series of other images. A second test used auditory stimuli to measure involuntary responses to a startling noise.

The researchers noted a correlation between those who reacted strongly to the stimuli and those who expressed support for "socially protective policies," which tend to be held by people "particularly concerned with protecting the interests of the participants' group, defined as the United States in mid-2007, from threats." These positions include support for military spending, warrantless searches, the death penalty, the Patriot Act, obedience, patriotism, the Iraq War, school prayer and Biblical truth, and opposition to pacifism, immigration, gun control, foreign aid, compromise, premarital sex, gay marriage, abortion rights and pornography.

The paper concluded, "Political attitudes vary with physiological traits linked to divergent manners of experiencing and processing environmental threats." This may help to explain "both the lack of malleability in the beliefs of individuals with strong political convictions and the associated ubiquity of political conflict," the authors said.

Source: Rice University

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