The idea that how we vote in elections may be down to biology rather than conscience will surprise (and probably offend) many people. But a wealth of new research shows that where we place our cross in the polling booth may depend as much on subconscious cues from our brain as it does on free will...

...Studies suggest that on average, and even across national boundaries, people who opt for the Left, and people who opt for the Right, tend to be identifiable not only by their stated ideologies but by their personalities and quantifiable psychological traits.

Psychologically, “liberals” (using the American sense of the term to describe people who tend to vote for mainstream Left-wing parties and hold generally progressive views) can be defined as being open to new experiences and more comfortable with nuance and difference.

And those who self-define as “conservatives” tend to prize order, tradition and certainty, as well as being suspicious of novel ideas and more distrustful of difference – at the extreme, they are psychologically “authoritarian” and inclined to view the world in black and white.

Can these fundamental ideological differences have any basis in biology? If so, this would mean a radical rethink of how we view humans as political animals – and give pause for thought for those who dismiss their political opponents as irrational, stupid or even evil. Recent research conducted at the University of Nebraska’s political physiology laboratory provides perhaps the most compelling evidence that we are often not aware of our brain’s deep-seated political “choices”.

Studies using eye-trackers to monitor gaze and attention patterns, for instance, show very different responses among conservatives and progressives. Conservative eyes go straight to threatening images, and stay there longer; liberals look more at appealing and enticing images.

Not only do these simple “approach” versus “avoidance” strategies for navigating the world match up neatly with personalities: they may color everything about how we respond to life, not just our political views. Exploratory and defensive strategies have even been found in “liberal” and “conservative” styles of videogame play.

More fundamental brain processes and even anatomical differences may also be involved. For example, a recent study by neuroscientists at University College of London found that the self-described conservatives had a larger-than-average right amygdala, the brain’s region for processing fear and threat.

Troublingly, this “psychology of ideology” research seems to remove our political views from the realm of conscious choice and free will. Neuroscience findings are backed up by genetic studies, which show a substantial heritability of core Left-Right ideology – 40 per cent or more of our differences seem to be rooted in genes. But it is important to emphasize that even if this figure is correct, that still leaves plenty of wiggle-room for people to develop and change over their lifetimes, based on the experiences they have.