Tuesday, October 13, 2009

Did my genes make me do it?

David Brooks of the New York Times seems to be heavily into neuroscience these days. Having dismissed evolutionary psychology some time ago, he's apparently not going at this to understand the genetics behind why some people vote Republican and others Democratic (though there are people doing just this), but perhaps instead in the hopes of understanding how people can be taught to vote Republican. He tells in today's column of his recent attendance at a conference on neuroscience, to his surprise a conference of and by the young. He says
Young scholars have been drawn to this field from psychology, economics, political science and beyond in the hopes that by looking into the brain they can help settle some old arguments about how people interact.

These people study the way biology, in the form of genes, influences behavior. But they’re also trying to understand the complementary process of how social behavior changes biology. Matthew Lieberman of U.C.L.A. is doing research into what happens in the brain when people are persuaded by an argument.

Examples he gives of the kinds of studies being done include:

Reem Yahya and a team from the University of Haifa studied Arabs and Jews while showing them images of hands and feet in painful situations. The two cultures perceived pain differently. The Arabs perceived higher levels of pain over all while the Jews were more sensitive to pain suffered by members of a group other than their own.

Mina Cikara of Princeton and others scanned the brains of Yankee and Red Sox fans as they watched baseball highlights. Neither reacted much to an Orioles-Blue Jays game, but when they saw their own team doing well, brain regions called the ventral striatum and nucleus accumbens were activated. This is a look at how tribal dominance struggles get processed inside.
Brooks' point seems to be that people are malleable, and can be socialized to overcome tribalism or anti-social behaviors -- he has been writing about this for years, contending that poor Americans need to emulate the behaviors of middle and upper class families to have any chance of success. Once we understand how the brain works, he suggests, then policy wonks will "see people as they really are".

But how will that help, really? Even if neuroscientists show us that culture is taught, and people are teachable, who gets to decide who's the best role model? David Brooks thinks he knows, but so do Glen Beck and Rachel Maddow--and the rest of us. So, even if we ever do understand how the brain works, the politics won't get any cleaner or easier.

To us, though, the point is deeper than this. What it takes for major league pitchers to learn to throw a baseball so skillfully, and for violinists to learn to play the violin, and for anthropologists to learn to age and sex skeletons is practice--maybe 10,000 hours of practice. We didn't evolve 'to' do calculus, or play the violin, or throw a baseball or to agree or disagree with Rush Limbaugh, but instead to be able to learn how to do these things (although Alfred Wallace, the co-discoverer of evolution, became quite spiritual in later life, certain that humans were above nature because we could do calculus; he couldn't imagine how our ability to do math could have evolved).

The brain is plastic--learning changes synapses. Indeed, physiological changes in the brain from learning new tasks are measurable, as reported in a recent Nature Neuroscience paper on changes in the density of gray and white brain matter in subjects learning to juggle, described here. And, CNN is reporting on their website today about a woman who apparently had a stroke prenatally which destroyed half of her brain; many of the functions stereotypically performed by the missing part of her brain have been taken over by the active side.

It is natural, especially within western culture with its focus on cause and effect, to seek (or hunger for) simple causes for 'effects' we are interested in. We put the word in quotes because from the inquiry point of view what constitutes an 'effect' is often quite subjective. Is the party you vote for a meaningful effect, or is your vote based on deeper issues that, at present, you find affiliated with some particular party?

It is easy to think about finding the gene 'for' some specific effect, especially if you define the effect meaningfully. It's the view that evolution has hard-wired us for the effect, DNA being the prescriptive cause. But that may have things quite backwards. It makes more evolutionary sense that organisms be programmed to be facultative in sensing, assessing, and responding to the environment. If the human brain is anything it is like that rather than hard-wired for voting this way or that. Even ants, as Darwin observed, seem quite intelligent if we shed our anthropocentric biases.

However, it is much, much more difficult to think of understanding the genetic basis of facultative assessment and response, than of hard-wiring. We don't have good ways to define the trait, much less to find its genetic basis. Yet, clearly, that is the trait we should be trying to understand.


Holly Dunsworth said...

Nice link between today's Op-Ed and the white matter news in Nature Neuroscience and nice synthesis of present, past and prehistory.

Anne Buchanan said...

Thanks, Holly. Since I'll never be a pitcher, guess I'll go practice my juggling now.