I’d like to talk about two points that at first blush seem quite unrelated. One centers in hard biology and neuroanatomy; the other in the softest sort of social science. Yet both converge to undermine the scientific case for a primarily environmental explanation of the race gap in IQ. Together, they show how, over time, the ground that explanation has left to stand on shrinks inexorably.
The first topic is some relatively recent and ongoing work on the relation between features of white matter in the brain and IQ. The second is the so-called Obama Effect, which some have claimed has allowed some blacks to overcome the disadvantages they had had with respect to whites in performance on tests of cognitive ability.
I end by describing the contrived sort of counterarguments one now sees from advocates of basic genetic equality across races.
White Matter and IQ
An article in most recent Technology Review depicts some work that researchers at UCLA and elsewhere have in recent years conducted on the relation between the features of white matter in the brain and intelligence. (A previous article had discussed in some more detail the apparent heritability of some of the relevant features of the brain.)
From this latest article:
If white matter plays a key role in intelligence, is there a way to enhance it? Does it give us ways to make ourselves smarter, or to help people with neurological and psychiatric disorders that affect cognitive skills?
It’s likely that the quality of white matter is at least partly genetically determined and, therefore, difficult to change. The size of the corpus callosum, the thick tracts of white matter connecting the two hemispheres of the brain, is about 95 percent genetic. And about 85 percent of the white-matter variation in the parietal lobes, which are involved in logic and visual-spatial skills, can be attributed to genetics, according to Thompson. But only about 45 percent of the variation in the temporal lobes, which play a central role in learning and memory, appears to be inherited.
Thompson is now trying to identify specific genes that are linked to the quality of white matter. The top candidate so far is a gene for a protein called BDNF, which promotes cell growth. People with one variation have better-organized fibers, he says.
But environmental factors also play a role. Rodents raised in a stimulating environment have more white matter. And research suggests that the apparent IQ difference between people who were breast-fed and bottle-fed as babies may arise because breast milk contains omega-3s, fatty acids involved in the production of myelin; as a result, some baby formula now includes these compounds.
Now this passage bows to the notion that environment, in the form of intellectual stimulation, might play a major, perhaps dominant, role in IQ. The reader may choose, in the interests of comfort, to interpret this as providing the hypothesis of essential equality-for-all with an “out” — and no doubt that has much to do with why this verbiage was offered up. But it’s really hard to understand the facts described here as suggesting such equality is a likely outcome.
Consider an analogy. Most people seem to take it as pretty well established that races differ genetically in the quality of their muscle fibers, and other aspects of their musculature, so that, other things being equal, members of one race — blacks with sub-Saharan African ancestors — tend to be faster sprinters than others. Granted this, is it in any way implausible races might likewise differ in the size and quality of their white matter as it pertains to IQ?
Of course it is not unlikely that exercise of the brain, in the form of stimulation, alters the size and quality of white matter. Certainly learning must affect the brain in some physical way, otherwise how might it take place? Yet return to the analogy of sprinting. Dedicated practice will improve the muscle and sprinting performance of virtually anyone willing to engage in it. Yet no program, regardless of its intensity and design, has proved adequate to turn whites or Asians into world record sprinters against the inherent advantages of blacks, nor, one would expect, would any regimen of exercise much affect a gap between the average sprinting performance of blacks on the one hand and whites and Asians on the other.
Why believe, then, that brain stimulation will prove adequate to removing average differences between the races in terms of IQ, or the hypothesized physical substrate for IQ, the nature of the white matter?
Again, one can always find a way to salvage the thesis of basic equality between the races on this score. One can dismiss the study of white matter as simply off-base and wildly speculative. One can say that all relevant white matter differences might be entirely due to proper stimulation in the environment. One can say that while such differences might be highly genetic within a race, there’s no reason to believe that they are so between races. Most of these arguments can be advanced pretty much regardless of whatever science might find, now or for some significant time into the future.
Yet their plausibility at some point surely dies even in the eyes of those who might most ardently wish to believe them. As science uncovers more and more precise physical correlates for IQ, as those are shown to be inherited, as those differences are shown to be reflected across races, and, finally, as the particular genes that effect those differences are in the future both identified and shown to be differentially distributed across races, then the vice of science gets the truth in an inescapable grip. And it is a truth in which genetics is the key to IQ.
Even at this stage, I believe, the hope for ultimate equality here is pretty much a hope for a miracle. The brain science recounted above is doing no more than converging on the only truth we might reasonable expect, given what we already should know if we have an inclination to objectivity, just as the identification of the genes involved will simply flesh out facts by now well confirmed in other ways.
The Obama Effect
In the course of President Obama’s recent election campaign, some researchers (David M. Marx, Sei Jin Kob and Ray A. Friedman) devised a study that purported to show that there was a major “Obama Effect” on the performance of blacks on IQ-like tests of cognitive ability. This study, at the time, got major play in a number of high visibility media venues.
Here’s the abstract of the original research article:
Barack Obama, the first Black-American president, has been widely heralded as a role model for Black-Americans because he inspires hope. The current study was conducted to assess whether, beyond simply inspiring hope, this “Obama Effect” has a concrete positive influence on Black-Americans’ academic performance. Over a three-month period we administered a verbal exam to four separate groups of Black- and White-American participants at four predetermined times. When Obama’s stereotype-defying accomplishments garnered national attention – just after his convention speech, and election to the presidency – they had a profound beneficial effect on Black-Americans’ exam performance, such that the negative effects of stereotype threat were dramatically reduced. This effect occurred even when concerns about racial stereotypes continued to exist. The fact that we found performance effects with a random sample of American participants, far removed from any direct contact with Obama, attests to the powerful impact of ingroup role models.
Now even a number of those who are more than sympathetic to the idea that “stereotype threat” is a real phenomenon were not happy with the methodology of the study, which was indeed quite sloppy. And in fact a least one such researcher, Joshua Aronson of NYU, conducted a study in which the Obama Effect was not replicated (though at least from its description in its own abstract, it may have had a methodological issue of its own: the study was conducted in the context of Obama’s Presidency, and, if there were an Obama Effect, it might already have been fully in force for both the experimental and control groups of black students in the study).
But in the end it’s important to see how any Obama Effect might come out in the larger statistical wash — and in such matters there’s no statistical wash better than SAT scores. They apply to broad, nationwide swathes of the relevant student population, and in numbers so large that even the smallest effects should be readily detectable.
What do SAT scores tell us?
Here’s the comparison between the 2007, 2008, and 2009 total SAT scores.
Each year is for the graduating class of the specified year, and comprises scores from May of the previous year through March of the year of interest. (Thus 2009 results comprehend tests taken from May of 2008 through March of 2009). Obama’s campaign and Presidency clearly would have been most on people’s minds in the 2009 results, and rather little going back to 2008. I have also, however, included the 2007 results for comparison, if some might think that an Obama Effect might have already been working into the 2008 results. With regard to the 2009 results, it may be worth noting that at least some students took the test on Jan 24, 2009, merely days after Obama’s inauguration, when an effect against stereotype threat might have been especially powerful.
I think the truly remarkable thing about this data is the absolute dead on stability in the scores. Blacks may have lost a few points in 2009 (as well as in 2008 from 2007) — which is movement in the wrong direction, obviously — but that loss is quite trivial and perhaps explicable by a slightly larger number of black students taking the test. Yet if stereotype threat is a major factor in the always significantly depressed black scores, how can such an epochal event as the election of a black President — and one storied for his brilliance — fail to increase those scores in any measurable way? Bear in mind: these scores were for over 1.5 million students, 40% of which were minorities. At that scale, even the smallest real differences should be discernible. In contrast, the study Aronson conducted that failed to show an Obama Effect included only 119 students, who had to be distributed among experimental and control groups of both blacks and whites. In such a small study, even a real and important effect could easily be missed.
For someone who believes that stereotype threat accounts for a significant portion of gaps between groups on measures of cognitive ability, I don’t see how this SAT data might not shake their faith. The utter failure to find even the smallest effect in the SAT scores after a watershed moment such as the election of Obama could hardly be less in keeping with what they would seem to believe. If stereotype threat means anything, shouldn’t such a confidence booster and stereotype buster as the election and celebration of a black President of famous intelligence do something very real to affect a black student’s concentration and effort in a test of cognitive ability? Aren’t the very studies that seem to demonstrate such an effect so constructed that this sort of experimental manipulation is utilized, except in seemingly less consequential manner, in which the experimental subjects may be, for example, simply reminded of their race or gender? Shouldn’t so powerful a rebuttal of the stereotype under which a student labors improve his or her ability to think while taking a test, if it was that stereotype which exerted such a dramatic distracting and confusing effect to begin with? What’s left of stereotype threat if stereotype refutation is empty entirely of consequence?
While of course proponents of the theory of stereotype threat can always insist on making distinctions here to preserve their hypothesis, doesn’t continued assertion of that theory start to feel a trifle, well, desperate? (One is struck by how often such explanations as stereotype threat and “caste mentality” appear to take on the logical role of being a factor X that essentially saves the environmental thesis against any and all possible counterevidence; they appear to get asserted with greatest vehemence exactly when all other environmental accounts seem to fail, for all practical purposes rendering the environmental hypothesis unfalsifiable.)
Equality of the Gaps
The belief in inherent equality across races in IQ has been derided as “Liberal Creationism”. The jibe is certainly well deserved. But perhaps the analogy might be even more on point were it described as “Liberal Intelligent Design”. For the defense of equality posed by more sophisticated liberals tends to be far more elaborate than the mere invocation of dogma which constitutes Creationism. It is much more akin to the detailed, if utterly strained, arguments of Intelligent Design (ID) proponents.
To every scientific difficulty in their views, liberal advocates of equality have some answer: all physical correlates of IQ can be induced by environment; differences within groups tell us nothing about differences across groups; IQ tests are culturally biased; race is a construct; it’s the “caste mentality” or “stereotype threat” in blacks that depresses their IQ scores; etc.
The problem is, as science has progressed, the ability to maintain the relevance of these counterarguments becomes more of an act of deep faith in a contrary proposition than anything resembling rational inference.
ID proponents might be regarded as adopting a God-of-the-Gaps argument. ID mostly focuses on those biological or chemical facts lying behind evolution that scientists have not yet adequately explained, and trumpets that lack of resolution or understanding as “proof” that only an intelligent designer might have brought about such a phenomenon. Likewise, liberals who insist that there is no scientific evidence of genetic differences between races in IQ seek out aspects of the scientific case for such differences which are not fully understood, and insert their belief in equality in those gaps. Their view can, I think, aptly be named “Equality of the Gaps”. Under this approach, if studies show that black children adopted into families register IQs far more similar to the average of blacks in the larger population than to the IQs of white children adopted into the same families, then the explanation must lie elsewhere than genetics. It must be that black children suffer in all cases from a “caste mentality” brought about their very identification as black, or that they, as blacks, are punished by peers for “acting white” when they seek to excel at school. If white matter in the brain appears to play a crucial role in IQ, then either the relevant differences in size and quality are in all cases brought about entirely by environment, or the differences between races on this score are so engendered. And if science is not yet fully clear as to which sets of genes differentiates between races, and in what manner they do so, then race is a mere social construct, not a category grounded in biology.
Each individual response may possess some kind of plausibility (or not). In aggregate, however, it’s impossible not to notice the pattern. These moves are quite completely predictable. They appear to be driven by beliefs that have absolutely nothing to do with science or the truth, but rather spring from a fragile and ill-conceived moral system — one far too rigid to accommodate important facts of human nature.
Where does this leave the ongoing argument over IQ and race?
Over time, as science has closed in on the underlying truths, the gaps in explanation have narrowed dramatically; they continue to do so. Yet those gaps never entirely disappear. For the Equality-of-the-Gaps people, that is all they require: they live on to fight another day, and another day after that. For the rest of us, we can only wait it out until they dwindle into irrelevance.
A true paradigm shift is probably never a pretty thing seen up close.