"Previously, some psychological traits were known to be predictive of an individual's political orientation," said Ryota Kanai of the University College London. "Our study now links such personality traits with specific brain structure."
Kanai said his study was prompted by reports from others showing greater anterior cingulate cortex response to conflicting information among liberals. "That was the first neuroscientific evidence for biological differences between liberals and conservatives," he explained.
The study, entitled "Political Orientations Are Correlated with Brain Structure in Young Adults" (PDF), is online here.