Wednesday, November 28, 2007

Your brain on politics: the bad and the better

The bad
A disturbingly bad article, entitled "This is Your Brain on Politics", appeared recently in the New York Times. It presented purported "research" about the brains of swing voters in the 2008 US Presidential Elections but, unfortunately, the article does little but illustrate the dangers of circumventing the peer-review process and the shocking state of science journalism in the mainstream media. Luckily, the NYT published an angry letter by a group of cognitive neuroscientists condemning the article and the blogosphere responded forcefully, among the blogs that attacked the piece were: Bad Science, Neurocritic, Mindhacks, Brainethics and Natural Rationality. Subsequently, Nature published an editorial also condemning the article and even Slate joined in.

The better

Blogging on Peer-Reviewed ResearchThankfully there has also been some better recent research concerning 'the brain on politics' and good media coverage thereof to boot. The subject of last week's edition of ABC Radio National's fantastic radio show/podcast, All in the Mind, was "The Political Brain" and the show discussed, among other things, an interesting study in Nature Neuroscience entitled "Neurocognitive correlates of liberalism and conservatism" (see also the supplementary materials). The study, led by NYU assistant professor of psychology David Amodio, evoked considerable interest and was widely discussed by the science blogging community. (See links below). I suspect the study has been somewhat misunderstood, so, despite it being stale by web standards, I'll look at it in some detail.

The hypothesis the authors defend is that political orientation (conservative vs. liberal) is "associated with individual differences in a basic neurocognitive mechanism involved broadly in self-regulation" (Amodio
et. al., 2007: 1246). They go about testing this proposition in a somewhat tortuous way: previous research had shown that conservatives are "more structured and persistent in their judgments and approaches to decision-making" whereas liberals "report higher tolerance of ambiguity and complexity, and greater openness to new experiences". Other research showed that psychological differences between liberals and conservatives "map onto the... self-regulatory process of conflict monitoring" (the system that detects a mismatch between habitual responses and the response required in the current situation) which in turn has been "associated with neurocognitive activity in the anterior cingulate cortext"(ACC). So, to test whether liberals and conservatives differ in their patterns of self-regulation, the authors measured the acitivity of the ACC in a situation requiring conflict-monitoring.

Amodio
et. al. conducted this test by using an electroencephalogram to record the ACC activity in 43 subjects who were asked to complete a go/no-go association task (Nosek & Banaji, 2001). For the task, participants were placed in a sound-proof room, in front of a computer screen in the center of which either an "M" or a "W" appeared. Half the subjects were instructed to "go" (i.e. hit a key) when they saw an "M" and do nothing ("no-go") when they saw a "W", while the other half were asked to do the opposite. The task consisted of 500 trails, 80% of which consisted of the "go" stimulus and 20% of the "no-go" stimulus. This meant that for half the subjects "M" became a habitual response (which needed to be inhibited when they saw a "W") and for the other half "W" became habitual (which needed to be inhibited when they saw an "M"). Additionally, before the task was administered, subjects reported their political attitudes confidentially on a scale ranging from -5 (very liberal) to +5 (very conservative).

The results were very suggestive. Firstly, however, it is important to note that there are in fact two types of finding in this study: the behavioral findings (which the authors do not focus on) and the cognitive neuroscience findings (which the authors emphasized and most of the subsequent discussion revolved around). The behavioral finding - which is interesting all by itself - is that liberals were more accurate than conservatives on the no-go trails (r(41) = 0.30, P less than 0.05) which "suggests that a more conservative orientation is related to greater persistence in a habitual response pattern, despite signals that this response pattern should change".

The neurocognitive findings were (among other things) that the response-locked error-related negativity (ERN) - a measure of conflict between a habitual tendency and an alternative - was strongly correlated (r(41) = 0.59, P less than 0.001) with political attitudes:

Additionally, liberalism was strongly associated with greater conflict-related neural activity when a habitual response had to be inhibited:


Subsequently, localization analysis was performed, which confirmed that the above mentioned ERN activity originated from the ACC. Amodio
et. al. conclude that "taken together, our results are consistent with the view that political orientation, in part, reflects individual differences in the functioning of a general mechanisms related to cognitive control and self regulation".

A couple of observations. The study is clearly preliminary and a good deal of the reporting of it in the lay press went far beyond the evidence. The authors, however, obviously cannot be blamed for this - they were careful not to stray from the evidence in their paper. Furthermore, only 43 subjects took part in the study and, worse, only 7 of those self-reported as conservative. The findings would have to be replicated by a different team in a different part in the US with a larger number of participants before too much stock can be placed in them. For now this can be filed under "interesting and suggestive but preliminary". We'll have to wait and see how the literature develops.


Links

Bibliography

Amodio, D.A., Jost, J.T., Master, S.L., Yee, C.M. (2007). Neurocognitive correlates of liberalism and conservatism. Nature Neuroscience, 10, 1246-1247. DOI: 10.1038/nn1979

Nosek, B. A., & Banaji, M. R. (2001) "The go/no-go association task,"
Social Cognition, 19(6): 161-176.

2 comments:

  1. For "P less than 0.05" (etc.) please read "P < 0.05". There was some nightmarish issue in HTML (something to do with the less-than sign interfering with the italics [], interfering with the image). I could find no other way of fixing it.

    ReplyDelete
  2. Remember padawan.

    Only the Sith deal in absolutes...and they're EEEEVIL

    ReplyDelete