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.

In other words, liberals are not as big a bunch of fuck-ups as conservatives. Case closed.

Study finds left-wing brain, right-wing brain - Los Angeles Times