This very interesting paper was just published online today in the journal Current Biology. See the abstract below. At least in young adults, political liberalism and conservatism appears to be correlated with brain structure. Conservatism correlated with bigger amygdala (the region that is responsible for fear), and liberalism was associated with increased grey matter volume in the anterior cingulate cortex. One of the functions of the anterior cingulate cortex is to monitor uncertainty and conflicts. The authors speculate that people with a larger anterior cingulate cortex may have a higher capacity to tolerate uncertainty and conflicts and that this would allow them to accept more liberal views. The finding about a bigger amygdala and conservative views seems in line with the observed fact that at least in America, the most conservative people also appear to be very susceptible to fear-mongering and to increased paranoia about out-groups.
Political Orientations Are Correlated with Brain Structure in Young Adults (link)
Current Biology, 07 April 2011
Copyright © 2011 Elsevier Ltd All rights reserved.
- Political liberalism and conservatism were correlated with brain structure
- Liberalism was associated with the gray matter volume of anterior cingulate cortex
- Conservatism was associated with increased right amygdala size
- Results offer possible accounts for cognitive styles of liberals and conservatives
Substantial differences exist in the cognitive styles of liberals and conservatives on psychological measures [1
]. Variability in political attitudes reflects genetic influences and their interaction with environmental factors [2
]. Recent work has shown a correlation between liberalism and conflict-related activity measured by event-related potentials originating in the anterior cingulate cortex [4
]. Here we show that this functional correlate of political attitudes has a counterpart in brain structure. In a large sample of young adults, we related self-reported political attitudes to gray matter volume using structural MRI. We found that greater liberalism was associated with increased gray matter volume in the anterior cingulate cortex, whereas greater conservatism was associated with increased volume of the right amygdala. These results were replicated in an independent sample of additional participants. Our findings extend previous observations that political attitudes reflect differences in self-regulatory conflict monitoring [4
] and recognition of emotional faces [5
] by showing that such attitudes are reflected in human brain structure. Although our data do not determine whether these regions play a causal role in the formation of political attitudes, they converge with previous work [4
] to suggest a possible link between brain structure and psychological mechanisms that mediate political attitudes.