Blue Brain Red Brain: Science predicts political preference

Which way does your moral compass point? When you read the news and suddenly feel a sense of injustice. Or outrage. Or more rarely, objectivity? When you write a check supporting the party of your choice. When you confidently select a box come election time. Why do you feel so strongly you have made the right choice? Science suggests we don’t have much choice, after all.

In 2011, Kanai and colleagues measured that grey matter volume (concentration of neurons) in three brain regions showed positive correlations with either liberalism or conservatism.  Indeed, they could predict with 71.6% accuracy which side participants preferred. The anterior cingulate cortex (ACC), amygdala and insula revealed distinctly different patterns when participants were asked to indicate their political orientation on a scale of very liberal to very conservative.  The brain of a liberal and that of conservative are very different, results showed.

If you lean left.

A liberal brain’s ACC is as noticeable as Barack Obama’s birth certificate. The ACC modulates tolerance to uncertainty, conflict and emotion monitoring and action selection. In other words, the larger this brain region – you will be less fearful of the unknown, you will have better control over emotions and you will tend to manage conflicts with poise.   The insula is also very active, which is responsible for interceptive perception and social processing.  That is to say, liberals are better at knowing the internal state of others so as to avoid cognitive conflict.

If you lean right.

A conservative brain’s amygdala and insula are as obvious as Donald Trump’s comb over. The amygdala governs reward, fear-response, pleasure, emotional information, risk and positive stimuli. Indeed, a 2013 study showed that

Conservatives have an intense physical reaction to threatening stimuli compared to liberals that conversely, have an intense physical reaction to cognitive conflict.

In the same study, participants were asked to complete a simple-risk taking decision-making task during which they were presented with three numbers in ascending order (20, 40, 80) for one second each. They were told pressing a button during the presentation of the number 20 would earn them 20 cents, but waiting to select 40 or 80 was associated in either gaining or losing 40 or 80 cents.  So, they could definitely win 20 cents, or wait and risk gambling with more money.   The study built on the previous one by adding the element of behavior and its relationship to partisanship. Republicans more strongly activated in their right amygdala, associating with orienting attention to external cues. Democrats showed activity in the insula, associated with perceptions of internal physiological states. So,

Republicans focus on external things when taking risks while Democrats look inside for guidance. 

The study also surpassed its parent study by accurately predicting the participants’ party preference 82.9% of the time.

Chicken or Egg.

 So is your moral compass a product of genes or environment?  Science has not definitively decided. The brain can change and grow in accordance to its environment, i.e. the study that proved that London cab drivers have larger hippocampi (region related to memory formation).  However, the brain also dictates political choice evidenced thus far, by the amygdala and insula being larger in respective political parties. 

Whether you lean left or right, understanding our behavior will be essential in advancing our political attitudes and indeed as a result, make us more compassionate to the other side. Kanai, R., Feilden, T., Firth, C., & Rees, G. (2011). Political Orientations Are Correlated with Brain Structure in Young Adults Current Biology, 21 (8), 677-680 DOI: 10.1016/j.cub.2011.03.017 Schreiber, D., Fonzo, G., Simmons, A., Dawes, C., Flagan, T., Fowler, J., & Paulus, M. (2013). Red Brain, Blue Brain: Evaluative Processes Differ in Democrats and Republicans PLoS ONE, 8 (2) DOI: 10.1371/journal.pone.0052970
Kanai R., Colin Firth & Geraint Rees (2011). Political Orientations Are Correlated with Brain Structure in Young Adults, Current Biology, 21 (8) 677-680. DOI: