Deep-seated political differences aren't simply moral and intellectual: They're also biological.

In reflex tests of 46 political partisans, psychologists found that conservatives were more likely than liberals to be shocked by sudden threats.

Accompanying the physiological differences were deep differences on hot-button political issues: military expansion, the Iraq war, gun control, capital punishment, the Patriot act, warrantless searches, foreign aid, abortion rights, gay marriage, premarital sex and pornography.

"People are experiencing the world, experiencing threat, differently," said University of Nebraska political scientist John Hibbing. "We have very different physiological orientations."

The study, published today in Science, has not yet been duplicated, but adds a potentially troubling piece to the puzzle of biology, behavior and politics.

Earlier studies have linked reflexive responses to threats – which for testing purposes take the form of loud noises and graphic images – with existing states of heightened anxiety.

Though the Science study's authors cautioned against an overly broad interpretation of their findings, the results suggest that fear leads to political conservatism.

"Threatening situations do indeed seem to increase people's affinity for politically conservative opinions, leaders, and parties," said New

York University psychologist John Jost.

Study co-author Kevin Smith, also a University of Nebraska political scientist, demurred at making such a connection. "Historically speaking, politicians have appealed to the 'be afraid' response in the electorate in an attempt to mine votes," he said. "But in terms of going from campaigning to what we did in the laboratory, that's a large leap."

But even Smith agreed that "people with stronger responses are more sensitive to potential threats in their environment."

Asked whether the findings imply a fearmongering strategy for conservatives, New York University psychologist David Amodio responded, "Yes.

And some people believe that they are actively using this strategy."

The Bush administration has been accused of exploiting fears, though it's hardly a new approach.

"The whole aim of practical politics," wrote journalist gadfly H.L. Mencken,

"is to keep the populace alarmed (and hence clamorous to be led to safety) by menacing it with an endless series of hobgoblins."

Jost condemned such tactics. "From an ethical standpoint, conservative campaigns should not exploit feelings of fear in the general population," he said.

Of course, ethics tend to be forgotten during election seasons – but fear-mongering may be counterproductive.

"From a practical standpoint, I think that there will eventually be a backlash against those tactics as it becomes more obvious how exploitative they are," said Jost.

Darren Schreiber, a University of California, San Diego political psychologist, contends that a candidate "who merely tries to trigger fear simply can't be successful in the long run. Joe McCarthy had his run, but now his name is synonymous with a vile form of politics."

Exploitation aside, there may be a gentler side to the findings.

"Instead of political opponents thinking their opposite party is simply being willfully bullheaded," said Hibbing, "you can say, 'Well, they see a little differently than I do.'"

Political Attitudes Vary With Physiological Traits [Science] [not yet online]

Images: A terrorism awareness poster in London, circa 2002, courtesy of ToastyKen; differences in automatic responses to threatening stimuli, from Science.* *

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