Red Brain, Blue Brain: Politics and Gray Matter

The following findings have nothing whatsoever to do with the fact that they come from scientists at New York University, which is situated in what is arguably one of the bluest neighborhoods (Greenwich Village) of the bluest borough (Manhattan) in the bluest city (New York) of one of the country's bluest states (New York). What they've found, basically, is that political conservatives don't, won't and can't change their minds, reverse a decision or revise a judgment no matter how much contradictory evidence stares them in the face. Liberals? They, say the scientists, "report higher tolerance of ambiguity and complexity, and greater openness to new experiences." The study appears today in the online edition of Nature Neuroscience.

In all fairness, the study is rigorous in its design and execution. It is also the next beat in a series of advances in understanding what underlies political beliefs. In round one, psychologists took the lead: they studied the behavior and personalities of self-described liberals and conservatives. (Let me add a cautionary note here: in most of these studies, people place themselves along the political spectrum from right to left, typically from +5 for very conservative to -5 for very liberal. Obviously, how you rate yourself is not only subjective but relative to those around you. Someone in red-state Idaho who considers herself a liberal -3 because she doesn't think gay men should be fired from their jobs because of their sexual orientation might be more like a conservative +3 in, say, Greenwich Village because she also regards gay marriage, civil unions and adoptions as abominations.)

OK, but let's say the self-ratings have some validity. Psychologists repeatedly find that conservatives are "more structured and persistent in their judgments and approaches to decision making," and have greater "personal needs for order, structure and closure," as the new paper puts it. Liberals, on the other hand, are more tolerant of "ambiguity and complexity," and more open to new experiences.

Round two is being waged by neuroscientists wielding the latest in brain-imaging toys. For the current study, led by David Amodio of New York University, the scientists used a technique called event-related potentials, which measures electrical activity due to the concerted firing of neurons. They had their 43 subjects play a game of Go/No-Go, in which they have to quickly respond to a stimulus that means "go" (such as seeing a red triangle on the computer monitor, which means "press a button"). The go stimulus appears over and over and over, so you get used to pressing the button. Then, out of the blue, comes a no-go stimulus, such as a green circle. You have to stifle your button-pressing habit.

When their brains needed to recognize the conflict between their habitual response (press button) and the new information (a no-go stimulus), liberals and conservatives looked as different as, well, red and blue. Liberals showed much greater activity in the part of the brain called the anterior cingulate cortex, which recognizes conflicting information or signals; they were also more accurate at repressing the button presses. The more liberal they were, the more accurate they were. The brains of conservatives, on the other hand, showed less activity in response to a signal (no-go) that conflicted with their expectations (go) and habits of thought.

Liberalism, conclude the scientists, "is associated with greater neurocognitive sensitivity to cognitive conflict" between, say, what they believe and the evidence before their eyes.

The reader is referred to the correlation between political ideology and the belief that, for instance, after the 2003 invasion weapons of mass destruction were discovered in Iraq. A 2004 poll in Britain, for instance, found that "Labour supporters (58%) are more likely than Conservatives (42%) or Liberal Democrats (41%) to believe that Iraq had weapons of mass destruction"; see also here and here.

Does this mean some people are hard-wired for liberalism and others are hard-wired for conservatism? No. Not only is the very idea of hard wiring passe, but there is a growing recognition among neuroscientists that experiences and thoughts act back on the physical stuff of the brain that produces them. In other words, resist the easy interpretation that some innate pattern of activity in the anterior cingulate makes you fall in a particular spot on the political spectrum. More likely, thinking and believing a certain way affects the conflict-detecting circuitry in the anterior cingulate. What and how you think alter the structure and function of the brain.

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