With Election Day coming up, you might already know how you're voting, and now research shows that others might be able to predict which way you tend to lean, too. According to a new study, why you identify with a certain political party is influenced by biology.

To be described in an upcoming issue of the journal Current Biology, an international team of researchers found that the strength of a person's reaction to repulsive images can forecast whether they are liberal or conservative.

"Disgusting images generate neural responses that are highly predictive of political orientation even when those neural responses don't correspond with an individual's conscious reaction to the images," Read Montague of Virginia Tech, the study's lead author, said in a press release. "Remarkably, we found that the brain's response to a single disgusting image was enough to predict an individual's political ideology."

Montague and his colleagues showed study participants various disgusting images, such as dirty toilets or mutilated carcasses, mixed with neutral and pleasant images like landscapes and babies, all while hooked up to a brain scanner. Then, the subjects took a standard political quiz of sorts, answering questions having to do with controversial topics like gay marriage and abortion.

Astonishingly, the brain images revealed that responses to the sordid images could predict, with 95 to 98 percent accuracy, how a person would answer questions on the political survey.

"We pursued this research because previous work in a twin registry showed that political ideology - literally the degree to which someone is liberal or conservative - was highly heritable, almost as heritable as height," said Montague.

According to the results, for some unknown reason, conservatives tended to elicit a more magnified response to the ghastly images. The study demonstrates a clear biological difference between members of opposite political parties; however, the root of that difference has yet to be determined.

The researchers do believe though that these findings may one day help to bridge the gap that divides liberals and conservatives and create a friendlier political environment.

"In the same vein," Montague said in a statement, "if we can begin to see that some 'knee-jerk' reactions to political issues may be simply that - reactions - then we might take the temperature down a bit in the current boiler of political discourse."