Depending on who you talk to, Sarah Palin is either a hard-talking breath of fresh air or a fear-mongering greenhorn. Now research suggests that such different reactions – and perhaps all political beliefs – might have a basis in biology.

“Traditionally, political scientists have focused on the environmental aspects: school, the media, the family, the church, as the things that lead to beliefs they have,” says Douglas Oxley, a political scientist at the University of Nebraska, in Lincoln.

However, his team discovered that social conservatives react more strongly to shocking images and sudden noises by sweating more and blinking harder, compared to liberals. Such innate threat responses point to a biological, and perhaps genetic, basis for our politics, he says.

To uncover this trend, Oxley and Nebraska colleagues Kevin Smith and John Hibbing, quizzed 46 people on their political views, on topics ranging from the war in Iraq to capital punishment and premarital sex. All the participants had strongly held beliefs that identified them as socially liberal or socially conservative.


Two months after the survey, the researchers showed the subjects random pictures, while measuring how imperceptible changes in their perspiration affected skin conductivity.

When an image of a bloodied face or maggot-filled wound appeared, conservatives sweated more than liberals, even after accounting for differences that might be due to sex, income, age or education.

Fear reaction

The same trend held for blinking in response to a loud, random noise. Conservatives blinked a little bit harder than liberals, an innate response to a threat, Hibbing says.

This might be expected, based on the nature of the survey. Although political, the questions split people into socially protective and socially permissive groups. For the conservative views on issues like gun control and immigration, “these are all things that would help me stay safer with my social group”, Hibbing says.

“Liberals will probably say conservatives are scaredy cats,” while conservatives might call liberals naive, he says. “The more important point is that people differ”.

Exactly why we differ is unclear, says Rose McDermott, a political psychologist at Brown University in Providence, Rhode Island.

“Where does this come from? Is it social? Is it genetic? Of course, it’s not one or the other. The question is to look at the ways our biology interacts with the environment.”

Pointless debate?

Oxley and Hibbing suspect that some genetic differences underlie our political leanings. Previous research has shown that certain mutations affect how a region of the brain called the amygdala reacts to fearful images.

Such innate differences might explain why convincing a staunch Democrat to vote Republican is almost impossible. And vice versa.

“When we have two talking heads screaming at each other, they’re not going to convince each other of what they believe if they are pre-disposed to have those beliefs,” Oxley says.

With six weeks of increasingly bitter presidential campaigning ahead, voters may start to weary of the rancour, but such deep-held convictions could serve an important role. “It’s probably a positive thing if we have a mix of people who have beliefs in politics that are protective of society and also politics that are more risk-taking,” he says.

Journal reference: Science (DOI: 10.1126/science.1157627)