Are Liberals and Conservatives Hard-Wired to Disagree?

New research from London suggests we have different brain structures based on our political leanings


Last week's Congressional brinksmanship over the budget illustrated, once again, just how polarized the different camps in Congress have become. Granted, some amount of the distance between the public stances legislators took can be explained by a combination of maneuvering for votes back home and posturing for political gain in the constant power struggle that is Washington. But still. Watching the two sides argue, it was clear that they didn't just differ on details. There are entirely different worldviews behind each camp's budget proposals ... different enough that one might wonder if they're really all experiencing the same reality.

Well, according to neuroscientists in Britain ... they might not be.

In a report published last Thursday, neuroscience researchers from the Institute of Cognitive Neuroscience at University College London announced that they had found evidence that liberals and conservatives actually have different brain structures.

Cognitive neuroscientist Dr. Ryota Kanai and colleagues conducted MRI scans of 118 college students whose self-reported political views ranged from "very liberal" to "very conservative."   Many areas of the subjects' brains showed no difference based on political orientation. But the subjects classifying themselves as "liberal" had a higher volume of gray matter in the anterior cingulate cortex of their brains than study participants who classified themselves as "conservative." The anterior cingulate cortex is believed to play a role in helping people cope with and sort through uncertainty and conflicting information, as well as affecting their levels of emotional awareness and empathy. The "conservative" participants, on the other hand, had a higher volume of gray matter in the right amygdala region -- which is thought to play a big role in identifying and responding to threats.

The brain is incredibly complex, of course, and we are still only in the baby stages of understanding how and why it works the way it does. But in theory, someone with a larger amygdala would very likely be quicker to see threats and feel fear, whereas someone with a smaller amygdala but larger anterior cingulate cortex, given the same stimuli, would be more likely to consider other possibilities or explanations for that stimuli. The "larger anterior cingulate cortex" group would also be more likely to look at people the first group saw as threatening and see, instead, people in need of a helping hand.

This is not the first time researchers have looked for physiological or psychological underpinnings for our political viewpoints or worldviews. In his 2009 Atlantic article about the longitudinal Grant Study that followed 268 Harvard students throughout their lives, Joshua Wolf Shenk reported that  "personality traits assigned by the psychiatrists in the initial interviews largely predicted who would become Democrats (descriptions included 'sensitive,' 'cultural,' and 'introspective') and Republicans ('pragmatic' and 'organized)."

Indeed, Kanai said the MRI research was sparked by other recent psychological studies that found correlations between participants' functional behavior (accurately sorting through conflicting information, recognizing threats) and their stated political beliefs. In the MRI-based study, Kanai said, "We show that this functional correlate of political attitudes has a counterpart in brain structure."

But what does that mean? Are we hard-wired to disagree with each other from birth, because our brains process data from the world in fundamentally different ways? That question remains to be answered. It's possible that brain structure is set early, but it's also possible that it's influenced by experiences and environment. Kanai and his colleagues note in the report that other research efforts have already shown that brain structure "can exhibit systematic relationships with an individual's experiences and skills," and "can change after extensive training." And people certainly have been known to change their worldviews as they get older.

Clearly, Kanai and his colleagues are just scratching the surface of a very complex subject. But their research does raise some interesting questions. If experience does, in fact, influence brain structure, could a person exposed to high levels of legitimate threats over time develop a larger right amygdala to better respond to them? In other words, if you took someone who was a professed liberal and sent them to the front lines in Afghanistan for three years, would they return with a larger right amygdala, developed from an urgent need to identify and respond to threats every day? And along with that change in brain structure, would their political views shift to the right, as well? And what about children raised in a war zone? Do a great number of them end up with large right amygdalas? And, in turn, does that make them more likely to see the world in terms of threats and more absolute answers, with less tolerance for conflicting explanations or information, and less ability to feel empathy? If so, it might go a long way to explaining some of the entrenched positions in, say, the Israeli-Palestinian conflict.

Of course, that still doesn't explain people who've lived fairly secure lives but still see the world in terms of threats to be defended against, or people who've grown up in the middle of chaos and conflict and become peacemakers, overflowing with empathy and tolerance of conflicting complexity, even to a fault. What's more, few of us in mid-life see the world in as absolutely black-and-white clear terms as we did when we were 20. So another interesting follow-up would be to do a longitudinal study of brain structure over people's lifetimes, to see how those areas change. In fact, Kanai and his colleagues say as much in their report. "It requires a longitudinal study," the researchers conclude, "to determine whether the changes in brain structure that we observed lead to changes in political behavior or whether political attitudes and behavior instead result in changes of brain structure."

In any event, the University College study provides some biological proof for an important point: namely, that all of us see the world through lenses. None of us has a completely objective view of reality or truth -- a point that all of us would do well to remember. Imagine, for example, the difference in tone the debates in Congress might have if every legislator began by saying, "I recognize that I may view the same data differently than my colleagues because of the particular lenses or biases I have. But this is what I believe..."

Would it make a difference in the outcome? Possibly not. But somewhere in the recognition that our take on any given situation is not the only view, or the "right" or "obvious" or "logical" or "objective" view, but only our point of view ... lie the seeds for a more open, civil, and productive discussion.

But then, of course, that's just my point of view.

Image: melanieburger/flickr