Reviewed by John M. Grohol, Psy.D. on April 11, 2011
Emerging research suggests personality traits and even political orientation are linked to preferred use and corresponding size variance of different areas of our brain.
A new study suggests individuals who call themselves liberals are more likely to have brains that have a larger anterior cingulate cortex while conservatives have larger amygdalas.
According to what is known about the functions of those two brain regions, the structural differences are consistent with some reports showing a greater ability of liberals to cope with conflicting information and a greater ability of conservatives to recognize a threat.
The study is found in the online version of Current Biology.
“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.
Prior research has suggested that conservatives are more sensitive to threat or anxiety in the face of uncertainty, while liberals tend to be more open to new experiences.
Kanai’s team suspected that such fundamental differences in personality might show up in the brain.
Nevertheless, researchers cannot determine if the size of our brain structures shape personality, or if brain structures are shaped by what an individual experiences and believes over the course of a lifetime.
Further, things are usually more complicated with political views spanning a large spectrum rather than simply liberal or conservative.
“In principle, our research method can be applied to find brain structure differences in political dimensions other than the simplistic left- versus right-wingers,” Kanai said.
Perhaps differences in the brain explain why some people really have no interest in politics at all or why some people line up for Macs while others stick with their PCs. All of these tendencies may be related in interesting ways to the peculiarities of our personalities and in turn to the way our brains are put together.
Still, 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.”
Source: Cell Press