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How Neuroscience Supports Progressive Social Policy

Richard Nisbett’s new book, Intelligence and How to Get It SOURCE: W.W. Norton A raft of scientific evidence in recent years, along with a recent book, demonstrates that environment has a very strong impact on an individual’s brain development. The work effectively rebuts most of the lingering arguments over the controversial Bell Curve hypothesis.

Since the Bell Curve controversy of the mid-nineties, conservatives have often been quick to point out that the progressive commitment to science ends at behavioral genetics, since the evidence might point to some politically incorrect truths. These so-called “truths” usually concern the genetic basis for traits like intelligence and criminality. The thesis that Bell Curve, or “determinist,” conservatives have attempted to advance is that race or socioeconomic status can be correlated with genetics, and that this should inform social policies. If a trait is in the genes, their argument goes, then it must be immutable; therefore the social policies that are aimed at reducing crime or increasing educational attainment for certain racial or socioeconomic groups must be futile. In the words of Bell Curve co-author Charles Murray in a Wall Street Journal Op-Ed: “There is no reason to believe that raising intelligence significantly and permanently is a current policy option, no matter how much money we are willing to spend.”

For some time, the dialogue between conservatives and progressives on this issue has consisted of ad hominem charges. Consider John Derbyshire, writing recently at The Corner: “There is terrific social and political pressure on researchers, publishers, and commentators to put forward the most nurturist possible interpretation of every finding.” Some of the better-grounded discussions were able to delve into the empirical, methodological, and value-based assumptions as well as the statistical minutiae behind each side’s claims. (See William Saletan’s earnest, yet flawed, series on race and intelligence published last year in Slate and Stephen Metcalf’s critique of it.) Even though the connection between genes and IQ was subject to numerous caveats, the conservative genetic explanations for race and intelligence never really disappeared. This was due to the reductive appeal of genetic explanations for anything and the unfortunate persistence of educational inequalities.

For many years, it seemed the scientific jury was out and there was enough conflicting evidence to support any ideological bias. (This debate even makes for some strange ideological bedfellows, as it is easy, from the progressive vantage point, to agree with Leon Kass’s criticism of the Bell Curve. In this case, he is actually right about genetic explanations reducing the quality of human ability to mere quantity and the danger it poses to society by reinforcing prejudices.)

Fortunately, there has been a raft of scientific evidence in recent years demonstrating that environment matters much more than genes when it comes to an individual’s brain development and intellectual achievement. More importantly, this evidence has been making its way into the popular press and non-fiction, thus bringing digestible coherence to non-genetic explanations for intelligence. University of Michigan psychologist Richard Nisbett’s new book, Intelligence and How to Get It explains in rich yet accessible detail how myriad environmental stimuli can affect a person’s intelligence and educational achievement. This may seem obvious to many people, but the specific findings put forward by Nisbett and his colleagues demonstrate how policies, educational techniques, or environmental adjustments can improve the achievement of everyone from preschoolers mastering their ABCs to high schoolers taking the SATs. These findings are much more robust than the population-wide blanket correlations of the Bell Curve, which are used to advance the case for conservative “throw-in-the-towel” non-policies.

One of the best explanations Nisbett provides has to do with elucidating the concept of heritability, which many science popularizers misinterpret as the end-all-be-all calculation of nature versus nurture. In reality, heritability is about populations and the variability of the environment for the population being studied. Jim Holt draws attention to this in his review of Nisbett’s book in the New York Times:

Even if genes play some role in determining I.Q. differences within a population, which Nisbett grants, that implies nothing about average differences between populations. The classic example is corn seed planted on two plots of land, one with rich soil and the other with poor soil. Within each plot, differences in the height of the corn plants are completely genetic. Yet the average difference between the two plots is entirely environmental.

These claims are supported by research conducted by Eric Turkheimer of the University of Virginia, who has found that on measures of intelligence, middle-class and wealthy households are very similar; therefore differences within those groups are due more to genes. Poor households can vary widely, thus intelligence differences within that group are due more to the environment.

In a laudatory op-ed, the New York Times’ Nicholas Kristof runs off a list of Nisbett’s best recommendations about raising individual intellectual achievement: “Praise effort more than achievement, teach delayed gratification, limit reprimands and use praise to stimulate curiosity” —and collective intelligence. He goes on: “Professor Nisbett strongly advocates intensive early childhood education because of its proven ability to raise I.Q. and improve long-term outcomes…[and] suggests putting less money into Head Start, which has a mixed record, and more into these intensive childhood programs.” The Center for American Progress supports Head Start, but our education team feels it must be coordinated with high-quality state-supported early childhood programs and other federal and state programs for young children.

In a recent paper published in Proceedings of the National Academy of Sciences, Gary Evans and Michelle Schamberg from Cornell University find that poverty affects the physical and psychological health of poor teens through stress and inadequate nutrition. (The Washington Post and both covered the study.) With stress in particular, they were able to associate biological markers such as blood pressure and stress hormones with a decrease in working memory capacity. We employ working memory temporarily for remembering things like a phone number that we are about to dial. In their experiment, Evans and Schamber found that poor teenagers could remember an average of 8.5 items; better-off children could remember an average of 9.44 items. This is a significant difference and the differences remained when they controlled for variables such as parenting styles, maternal education level, birth weight, and parent marital status. The only time the differences were eliminated was when the stress indicators were controlled for.

Science Progress board member and University of Pennsylvania neuroscientist Martha Farah explained to me that greater cognitive stimulation in childhood creates more connections between neurons and that a more nurturing environment prevents abnormal development of the hippocampus, the region of the brain associated with forming long-term memories. These effects of stress on the brain are supported not just by hormonal and behavioral differences, but also by differences in brain shape, as evidenced by fMRI studies, and differences in brain electrical activity, as evidenced in event related potential, or ERP, studies, even when behavioral differences are absent. As detailed in Nisbett’s book, more qualitative social science research has shed light on the actual stress-inducing experiences of children who live in poor households, which can include more residential moving, greater neighborhood turmoil and disruption, or the lower levels of parental nurturance that result from parental stress. Farah mentions in the Washington Post article that for children, factors also include “having fewer trips to museums, having fewer toys, having parents who don’t…read to them or talk to them.”

Finally, it is only fair to mention that there has been some reluctance among progressive social scientists to focus on more than just the political and social aspects of educational achievement and poverty. The fear was that once scientists start to study the immediate environments or the neurobiology of poor people, it could be misconstrued as “blaming the victim” or, even worse, social Darwinism. However, when environmental and biological studies are done right, we see how they shed light on combining a top-down socio-political approach with a bottom-up bio-behavioral approach. This combined approach lies at the heart of evidence-based pragmatic progressivism. Already, the Obama administration has made a commitment of $10 billion to early childhood education, aimed at closing the achievement gap in public schools. The administration’s policy provides large-scale support for educators, community leaders, and parents who want to create a more supportive environment for their children so that they can succeed. Indeed, the science of the mind can further bolster the human-level empirical foundations for society-level public policies. From there, we can figure out how our educational system can both enhance our children’s abilities and point them in a successful direction, regardless of what those abilities might be.

Michael Rugnetta is a research assistant with the Progressive Bioethics Initiative at the Center for American Progress.


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