Study shows how liberals, conservatives think

This explains quite a bit: (emphasis added)

Exploring the neurobiology of politics, scientists have found that liberals tolerate ambiguity and conflict better than conservatives because of how their brains work.

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Participants were college students whose politics ranged from "very liberal" to "very conservative." Scientists instructed them to tap a keyboard when an M appeared on a computer monitor and to refrain from tapping when they saw a W.

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Each participant was wired to an electroencephalograph that recorded activity in the anterior cingulate cortex, the part of the brain that detects conflicts between a habitual tendency (pressing a key) and a more appropriate response (not pressing the key). Liberals had more brain activity and made fewer mistakes than conservatives when they saw a W, researchers said. Liberals and conservatives were equally accurate in recognizing M.

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Analyzing the data, Sulloway said liberals were 4.9 times as likely as conservatives to show activity in the brain circuits that deal with conflicts, and 2.2 times as likely to score in the top half of the distribution for accuracy.

So the net time you hear people bashing liberals...