Your brain’s response to vile images says a lot about your politics

Who’s she voting for, again?
Who’s she voting for, again?
Image: NBC
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Less than a week from Election Day in the US, a team of researchers has proved that your political leanings have a lot to do with biology—in, perhaps, a very strange way.

Scientists led by Read Montague at the Virginia Tech Carilion Research Institute showed a series of disgusting images—maggot infestations, rotting carcasses, mutilated bodies, and dirty toilets—to 83 participants, scanning their brains with an fMRI machine as they looked.

Then, the participants took a political ideology test, answering questions about issues like gun control, gay marriage, and illegal immigration. They also wrote down their reactions to the disgusting images.

The results? The brain’s response to disgusting images could predict with 98% accuracy whether someone leaned liberal or conservative. The participants’ written responses often did not match up with what their brains were showing. The brains of conservatives, on the whole, tend to react more intensely to gross stuff than the brains of their liberal counterparts. The brain, it seems, knows all.

“Remarkably, we found that the brain’s response to a single disgusting image was enough to predict an individual’s political ideology,” Montague said in a release for the study.

Political ideologies could be the biological progeny of the responses humans had long, long ago to contamination, disease, and other environmental threats. This discovery is part of a growing catalog of research that shows politics are not only biological, but often hereditary. That’s not to say your politics can’t change or adapt, but it’s very likely that your brain is already wired to think one way or the other.

The research is published in the latest issue of Current Biology.