Human behavior, where it intersects with neuroscience, has the potential to be highly contentious. The concept of free will is central, at least in monotheistic cultures, to most people's understanding of behavior. And no one likes being told that what they quite naturally consider to be their own ideologies or beliefs are a result of neurophysiological predestination. There are other pitfalls associated with delving into the neurocognitive roots of behavior; assume a genetic factor is discovered to be central to a behavior we deem aberrant? How long before the spectre of eugenics is raised?

On the other hand, can we reasonably expect science to simply ignore what is a fascinating and highly complex field? Because some might find the results challenging to their world view or unpalatable, ought we not ask the questions? Such research is conducted however, and thankfully we currently find ourselves living in a society where no one is being genotyped for behavior just yet.

An example of the research in question is published in Nature Neuroscience this week, and it's one that's making headlines. The study in question, from psychologists at NYU and UCLA, looks at how political self-identification relates to how the brain handles conflict. Volunteers rated their political affiliation on a scale from -5 to +5, and then had their brain activity measured as they performed a Go/No-Go test.

This involved being shown either a letter M or W on a screen. When they saw the M, they were to press a button (Go), but when they saw the W they were to refrain (No Go). To begin with, almost all of the signals are Go, resulting in a habitual effect where subjects instinctively press the button when they see the signal. When a No Go appears, the brain has to process the conflict between the habitual response to press the button and the knowledge that the letter is actually a W.

The researchers measured brain activity corresponding to an incorrect response, and discovered that political liberals showed significantly greater brain activity in the anterior cingulate cortex, and that liberalism, as compared to conservatism, was associated with greater sensitivity to cognitive conflict.

Now, that’s not to say that liberals have better brains than conservatives, regardless of how it might be spun, but the results of previous studies show that liberals show higher tolerance for ambiguity and complexity on psychological tests, and that conservatives tend towards needing greater structure and order. When one thinks about it logically, conservatives, by their own label, are not disposed to change, and it appears that we can see the evidence of this in brain activity.

Of course, the results should not be taken as pejorative; they don't claim to show that conservatives have lesser brains or neurocognitive function, despite how such conclusions might be spun. It does show that the way our brains are hardwired affects the decisions we make, even in the voting booth.

Nature Neuroscience, 2007. DOI: 10.1038/nn1979