Perhaps the reason that liberals and conservatives have such a hard time seeing eye-to-eye is because when they're compared brain-to-brain, they're built quite differently.

A new study that analyzed the brain structures of peoples' brains based on their political affiliations has found some significant differences.

Essentially, they found that liberals have more gray matter in a part of the brain associated with understanding complexity, while the conservative brain is bigger in the section related to processing fear.

The study, which appears in Current Biology, was conducted by Ryota Kanai of the University College London. Kenai's team looked at 90 healthy young adults who were given a survey and then asked to report their political views on a scale of one to five, from very liberal to very conservative. Their brains were then scanned.

People who reported that their views veered to the liberal side of the political spectrum tended to have a larger anterior cingulate cortex, which is a brain area involved in processing conflicting information.

Those with conservative views were more likely to have a larger amygdala, a region important for recognizing threats and processing fear.

"Individuals with a large amygdala are more sensitive to fear," and might therefore be "more inclined to integrate conservative views into their belief system," Kanai and colleagues wrote.

"On the other hand, our finding of an association between anterior cingulate cortex volume and political attitudes may be linked with tolerance to uncertainty" -- which may allow people to "accept more liberal views."

What the study couldn't answer was whether the structural differences they noted in the brains cause the differing political views, or are the effect of them.

Kanai says it's possible that brain structure isn't set in early life, but rather can be shaped over time by our experiences, which would explain why some people have been known to change their views over the course of a lifetime.

Kanai cautioned against taking the findings too far, citing many uncertainties about how the correlations they see come about.

"It's very unlikely that actual political orientation is directly encoded in these brain regions," he said. "More work is needed to determine how these brain structures mediate the formation of political attitude."