The big novelty story in the news this week is the study that is being reported as showing that liberals’ brains are wired differently and are better able to “tolerate ambiguity and conflict” than conservatives. Of course no one should ever trust public interest science reporting like this so those of you who have access to Nature Neuroscience can find the original journal article here. While the original article is careful to say nothing that is technically wrong¹ it is almost totally without real content. In particular the original journal article throws together what are essentially two unrelated results.

The study subjected volunteers to a test which required them to quickly press a button in response to a ‘go’ stimulus (for instance a green light) but not to do so when presented with a ‘no go’ stimulus (maybe a red light) and measured their ability to avoid pressing the button when a no go stimulus was presented after they were conditioned with many go stimuluses. They verified as had previously been suspected (or even known) that performance on this test was correlated with activity in the anterior cingulate cortex (ACC). They also noted that liberals tended to perform better at this task (less frequently press the button in response to a no go stimulus) than conservatives. Of course in the absence of confounding factors this will likely mean that liberal political orientation will tend to correlate with higher activity in the ACC and the article presents this correlation rather than breaking it down into separate claims as I did.

Now the conclusion of the report that:

Taken together, our results are consistent with the view that political orientation, in part, reflects individual differences in the functioning of a general mechanism related to cognitive control and self-regulation

is technically true but then again the fact that I’m not a six foot tall intelligent spider is also consistent with that conclusion. Of course the fact that

At the behavioral level, conservatives were also more likely to make errors of commission. Although a liberal orientation was associated with better performance on the response-inhibition task examined here, conservatives would presumably perform better on tasks in which a more fixed response style is optimal.

While this might seems suggestive that liberals and conservatives attitudes might stem from (deep seated) brain differences it is such week evidence that it should barely budge one’s prior probability. No effort seems to have been done to recruit a random sample of subjects from any particular population nor was any regression run to determine if the correlation persisted once other factors were discounted. For instance at a fairly liberal college campus it might turn out that people with lots of friends are going to experience greater social pressure to call themselves liberal and that people who are quicker at go/no go tasks are also quicker whits or more socially apt. A hundred other possible correlations could explain this result. Besides, I think our prior probability that liberal and conservative viewpoints would be correlated with fairly general cognitive features should be quite high. For instance in this era I suspect that being more strongly affected by reactions of immediate sympathy would probably turn out to correlate with liberalism and it would be amazing to me if no broad cognitive feature correlated with political affiliation somehow.

Unfortunately, either do to poor wording or deliberate attempt to make boring research seem more interesting the journal article functions as the perfect template for an urban legend. The introductory statement in the journal article that said

Across dozens of behavioral studies, conservatives have been found to be more structured and persistent in their judgments and approaches to decision-making, as indicated by higher average scores on psychological measures of personal needs for order, structure and closure. Liberals, by contrast, report higher tolerance of ambiguity and complexity, and greater openness to new experiences on psychological measures.

May be technically correct but the media is unlikely to understand “higher tolerance of ambiguity and complexity” as a technical term. Indeed they didn’t saying things like

Previous psychological studies have found that conservatives tend to be more structured and persistent in their judgments whereas liberals are more open to new experiences. The latest study found those traits are not confined to political situations but also influence everyday decisions.

and

Sulloway said the results could explain why President Bush demonstrated a single-minded commitment to the Iraq war and why some people perceived Sen. John F. Kerry, the liberal Massachusetts Democrat who opposed Bush in the 2004 presidential race, as a “flip-flopper” for changing his mind about the conflict. Based on the results, he said, liberals could be expected to more readily accept new social, scientific or religious ideas.

This is just silly. We could describe the exact same thing by saying, “Conservatives are more principled than liberals.” Hell in the sense meant in the article I tend to think that tolerance of ambiguity, while pragmatically useful, is a logical flaw². Unsurprisingly the association of the pretty banal results about behavior correlation with neurological activity tended to result in the impression that whether one was liberal or conservative was the result of inherent properties. When will people learn that all behavioral differences can be traced to brain differences.