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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, said the study on Thursday in Current Biology.

People with a large amygdala are “more sensitive to disgust” and tend to “respond to threatening situations with more aggression than do liberals and are more sensitive to threatening facial expressions,” the study said.

Liberals are linked to larger anterior cingulate cortexes, a region that “monitor(s) uncertainty and conflicts,” it said.

“Thus, it is conceivable that individuals with a larger ACC have a higher capacity to tolerate uncertainty and conflicts, allowing them to accept more liberal views.”