The neuroscience of political orientation

The new issue of Nature Neuroscience carries work from David Amodio’s group at New York University titled “Neurocognitive Correlates of Liberalism & Conservatism.” It’s a solid piece of basic cognitive neuroscience. The study’s claim to fame is that it “is the first study connecting individual differences in political ideology to a basic neuro-cognitive mechanism for self-regulation.” The paper is on very solid empirical grounds and makes very limited claims.

This did not stop William Saletan of Slate from publishing a sarcastic rebuke (“Liberal Interpretation: Rigging a study to make conservatives look stupid“) that is misleading, irresponsible and simply a bad piece of reporting. To find out what the research really says — and to understand what makes Saletan’s article such an embarassment to him, to Slate and to its readers — read on.

(Caveat: For a long time, Saletan was my favorite writer on Slate. I read his column religiously. As fantastic as John Dickerson is, I mourned when he replaced Saletan on Slate’s politics beat. Saletan’s recent science writing is another story.)

I won’t blame Saletan for his provocative title (“Rigging a study to make conservatives look stupid” — fighting words if there ever were any). I have my own penchant for catchy, over-the-top titles. However, Saletan wastes no time in setting up a straw man: “Are liberals smarter than conservatives? It looks that way, according to a study published this week in Nature Neuroscience.” These are his words, not Amodio’s. The study never discusses intelligence nor even uses the word.

The heart of Saletan’s article is meant to be a refutation of what he claims are the study’s central tenants: conservatives get stuck in habitual ways of thinking, are less responsive to information and less able to deal with complexity and ambiguity. He then proceeds to argue that the experiment outlined in the paper tests none of these things. His star witness: the paper itself:

“[E]ither the letter “M” or “W” was presented in the center of a computer monitor screen. … Half of the participants were instructed to make a “Go” response when they saw “M” but to make no response when they saw “W”; the remaining participants completed a version in which “W” was the Go stimulus and “M” was the No–Go stimulus. … Responses were registered on a computer keyboard placed in the participants’ laps. … Participants received a two-minute break halfway through the task, which took approximately 15 minutes to complete.”

Fifteen minutes is a habit? Tapping a keyboard is a way of thinking? Come on.

Well, when you put it that way, it does sound a little silly. But only if you put it that way. Saletan quoted directly from the paper’s methods section, and it comes across as faintly ridiculous when reproduced within a chatty Slate-style article. It would come across very differently if he had written:

In this experiment, participants watched letters flash on a computer screen. When they saw the target letter appear, they pressed a button. Otherwise, they did nothing. This is called a ‘go/no-go’ task and is heavily used in psychology and neuroscience as a test of attention and cognitive control. A quick PsychINFO database for ‘go’ & ‘no go’ finds 674 published papers, research covering everything from children with ADHD to baseball players.

It is a very simple task far removed from what most of us would consider ‘thinking,’ but scientists have found it to be very useful, precisely because it is so simple and easy to use. A major component of an IQ exam is a test where you have to repeat back a list of numbers. It may not sound like much, but performance on that task turns out to be very predictive of general intelligence. Plus, it’s a simple, easy-to-administer task, very much unlike trying to derive quantum mechanics from scratch, which is arguably a more common-sense test of intelligence.

That’s a crime of omission. Here’s the crime of commission: Saletan is arguing that the experiment fails to support the claim that conservatives get stuck in habitual ways of thinking, are less responsive to information and less able to deal with complexity and ambiguity.

What the paper actually says is that

Political scientists and psychologists have long noted differences in the cognitive and motivational profiles of liberals and conservatives in the USA and elsewhere. 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. Given that these associations between political orientation and cognitive styles have been shown to be heritable, evident in early childhood, and relatively stable across the lifespan, we hypothesized that political orientation may be associated with individual differences in a basic neurocognitive mechanism involved broadly in self-regulation.

In other words, previous studies have suggested that conservatives are less responsive to information, etc. The purpose of this study is to see whether conservatives and liberals differ on a “basic neurocognitive mechanism.” The paper goes on to show that the brain waves recorded when conservatives and liberals do the go/no-go task (a basic test of this neurocognitive mechanism) do in fact differ. (Strangely, although the paper’s focus is brain waves, this gets mostly lost in Saletan’s description.)

There is so much more fault to find with Saletan’s mistake, but I’ll finish with just one more. He writes, “The conservative case against this study is easy to make. Sure, we’re fonder of old ways that you are. That’s in our definition… If you studied us in real life, you’d find that while we second-guess the status quo less than you do, we second-guess putative reforms more than you do, so in terms of complexity, ambiguity, and critical thinking, it’s probably a wash.”

The Amodio study, as already pointed out, never claimed that conservatives are dumb or that their behavior is per se maladaptive. However, it does say this:

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.

It appears that Saletan’s conservative case was already made for him, by Amodio & co. It would be tempting to say that Saletan never read the paper, except that he quotes from it so much.

Slate has made its mark by putting news into context. Legal experts parse the latest supreme court rulings, putting them into historical and legal context so that we know what they really mean. Ex-corporate hot-shots interpret business news. Politicos give us a feel for what it’s really like on a campaign.

Saletan is the closest Slate comes to a full-time science writer, but he consistently fails to put science news into perspective. Often, he seems to completely misunderstand it. In this case, he should have explained exactly what the study was and what it wasn’t. He might have explained why the scientists used the methods that they did. He could have discussed how the study has been received in the media and pointed out mistakes and misreadings.

Basically, his post should have looked more like this one.