Subjects who professed liberal or left-wing opinions tended to have a larger anterior cingulate cortex, an area of the brain which, we were told, helps process complex and conflicting information. (Perhaps they need this extra grey matter to be able to cope with the internal contradictions of left-wing philosophy.) Conservatives, on the other hand, had a larger amygdala. This part of the brain was described as "very old, very primitive and to do with the detection of emotions". The take-home message was rather obvious: left-wingers are thoughtful, rational and able to cope with subtle ideas, while right-wingers are unevolved, instinctual creatures controlled by primitive emotions. One could almost hear the presenters' glee. As Gawker put it, here was the proof that "conservatism is a brain-disorder".
Professor Gereint Rees, who heads UCL's Institute of Cognitive Neuroscience, was heard declaring himself "very surprised" that there was such a clear-cut result, while the reporter, Tom Feilden, described it as "remarkable". But the write-up on the institution's own website hinted that the findings were not particularly new. In the case of the anterior cortex, "previous research" had "showed that electrical potentials recorded from this region during a task that involves responding to conflicting information were bigger in people who were more liberal or left wing than people who were more conservative." The amygdala result, meanwhile, was "consistent with studies which show that people who consider themselves to be conservative respond to threatening situations with more aggression than do liberals and are more sensitive to threatening facial expressions."
It's likely, then, that the researchers began looking at the data with some expectation of what they might find. A 2008 New Scientist article, indeed, contained this instructive pair of sentences:
Tasks that involve dealing with conflicting information, for example, are known to activate an area of the brain known as the anterior cingulate cortex (ACC). Since liberals are generally more open to conflicting ideas, activity in this area of the brain would be expected to differ between them and conservatives.
The same article mentioned other research into possible genetic influences on political opinions:
In a paper presented in April 2007 to the annual conference of the Midwest Political Science Association, held in Chicago, Ira Carmen, of the University of Illinois at Urbana-Champaign, discussed D4DR, a gene involved in regulating levels of the neurotransmitter dopamine. It is known that high levels of dopamine can cause obsessive-compulsive disorder. Carmen speculates that dopamine might therefore be linked to the need to impose order on the world. If so, variants of the D4DR gene that lead to higher levels of dopamine should be found more frequently in conservatives.
More recent work on the D4DR gene has pointed to a rather more subtle correlation: it appeared that those with a dopamine-suppressing version of the gene who have a wide circle of friends during adolescence were more likely to end up as liberals. Researchers speculated that such people would be more open to "different ideas" and, having many friends, would be more likely to encounter them. But it was not a large result. In any case, it's far from obvious that being open to unfamiliar ideas would turn someone into a left-winger. If you were, say, growing up in the Miliband household in the 1980s it would presumably be right-wing ideas that would strike you as new and exciting.
The stereotypes of both liberals and conservatives that feed into such studies make the results somewhat circular. If they reveal anything, it is about the roots of human personality rather than of political allegiance. It may well be that certain personality types naturally gravitate towards particular political parties or views: that authoritarian types are over-represented on the Right (though there are at least as many on the Left, in my experience) and social non-conformists look Left. But it would be dangerous as well as wrong to reduce the complexity of political debate to brain chemistry or genetics. There is, after all, no connection between the rightness or wrongness of a particular policy and the personality type most likely to find it appealing.
At the very least, there appears to be quite a bit of liberal self-congratulation on display in the reporting of these stories. Take the characterisation of the amygdala - supposed seat of conservatism - as a primitive and reptilian "fear centre". It is indeed an ancient part of the brain, but it is a fallacy to imagine that it hasn't evolved since the age of the dinosaurs, and an even greater one to assume (as the report invites us to) that the larger your amygdala the more primitive your psychology is likely to be. Actually, the reverse probably true. Also reported this week was a study into the relationship between the size of the amygdala and that of one's social network.
It was already known that primates with larger amygdalas tend to live in larger social groups. A Boston team led by psychologist Lisa Feldman Barrett measured the amygdala volume in 58 healthy adults using brain images gathered during magnetic resonance imaging sessions. After eliminating other possible factors such as age, social status or happiness, the researchers found - as they expected - that participants who had bigger and more complex social networks had larger amygdala volumes. This might, they suggested, be because those blessed with larger amygdalas were naturally more empathic and sociable.
If the UCL findings are to be believed, this new research suggests that far from being controlled by negative emotions, large-amygdala Conservatives are more socially-oriented and emotionally literate than the left-wingers whose organs are stunted and unevolved by comparison. This might explain why the Big Society has more natural appeal on the Right. Or perhaps it's just that Conservatives have more friends.
A very happy 2011 to all my readers, whatever the state of your amygdala.