From the Washington Post:

New brain science shows poor kids have smaller brains than affluent kids

By Lyndsey Layton April 15 at 7:27 PM

New research that shows poor children have smaller brains than affluent children has deepened the national debate about ways to narrow the achievement gap.

Neuroscientists who studied the brain scans of nearly 1,100 children and young adults nationwide from ages 3 to 20 found that the surface area of the cerebral cortex was linked to family income. They discovered that the brains of children in families that earned less than $25,000 a year had surface areas 6 percent smaller than those whose families earned $150,000 or more. The poor children also scored lower on average on a battery of cognitive tests.

Over the years, I’ve observed that your hat size correlates pretty closely with whether you believe brain size correlates with intelligence. I wear a 7 and 5/8ths hat, which is Extra Large, so the notion that brain size and intelligence are correlated always seemed pretty plausible to me.

My guess would be that head size is a tradeoff with running speed, via the mechanism of your mother’s pelvis width. The fastest runners tend to have very narrow hip bones, but that makes birthing babies with big heads dicier. I’ve always been an extremely slow runner, while the Kenyan Olympic champion runners looks to me like they have remarkably narrow heads.

I wonder, though, what Stephen Jay Gould’s hat size was? Gould got himself highly agitated in his 1981 bestseller The Mismeasure of Man over a 19th Century scientist who measured a sample of skulls of different races and found racial differences in skull volume. Gould accused the scientist of unconscious bias, but when the 19th Century experiment was redone recently, it turned out that old guy was right and Gould was in the wrong due to his flagrant bias. (See the 2011 New York Times Editorial “Bias and the Beholder” for details.)

The region of the brain in question handles language, memory, spatial skills and reasoning, all important to success in school and beyond.

The study, published last month in Nature Neuroscience, is the largest of its kind to date. It was led by Kimberly Noble, who teaches at both Columbia University’s Teachers College and the university’s medical school. Elizabeth Sowell, of Children’s Hospital Los Angeles, was the senior author.

“We’ve known for so long that poverty and lack of access to resources to enrich the developmental environment are related to poor school performance, poor test scores and fewer educational opportunities,” Sowell said. “But now we can really tie it to a physical thing in the brain. We realized that this is a big deal.” …

The research comes at a time when a majority of U.S. public school students come from low-income families and the academic achievement gap between poor and more-affluent children is growing. Policymakers are increasingly concerned about ways to reduce the gap, which is apparent as early as kindergarten.

In the last few years, there appears to have been a decision to blame racial differences in intelligence on differences in income level, although, of course, that’s not very plausible. That’s what people said way back in 1965, but then the federal Coleman Report of 1966 showed that affluent black students weren’t setting the world on fire academically on average, and vast amounts of data have accumulated validating the Coleman Report ever since.

But a half century later we’re back to asserting the same untested theories as in 1965.

In another study that has been accepted for publication in Psychological Science, a team led by neuroscientist John Gabrieli of MIT found differences in the brain’s cortical thickness between low-income and higher-income teenagers. The study linked that difference for the first time to standardized test scores: Fifty-seven percent of the poor children scored proficient in math and reading tests given annually in Massachusetts, compared with 91 percent of the higher-income students.

“The thing that really stands out is how powerful the economic influences are on something as fundamental as brain structure,” Gabrieli said. “It’s just very striking.”

Or perhaps brain structure has influences on economic performance? Or some of both?

The new research does not explain possible reasons for the brain differences. And that has created concern that the findings will harden stereotypes and give an impression that children who are born into poverty lack the physical capacity to succeed academically.

“Some people feel if you show these brain differences, you’re politically condemning the poor,” Gabrieli said. “Which is the opposite, I think, of what we need to do. I think we want to understand adversity and minimize adversity.”

Noble and Sowell have two theories about why poor children have smaller brains. One is that poor families lack access to material goods that aid healthy development, such as good nutrition and higher-quality health care.

That’s why there aren’t any poor blacks in the NBA. Their height and athletic abilities are stunted by poverty.

The other is that poor families tend to live more chaotic lives, and that stress could inhibit healthy brain development.

Could be. A more refined theory would be the one that Harpending and Draper put forward in 1982: father-absence causes kids, especially girls, to reach physical/sexual maturity faster, which stunts the final development of higher cognitive functions in favor of the development of low cunning. I don’t know if the evidence is there for this idea, but it’s not utterly implausible. I had a stable, organized childhood and grew up to be an unworldly intellectual.

Noble has embarked on a new study to try to answer that question.

She’s doing MRIs on the parents of her subject to see if it’s hereditary?

Nope.

She has begun a pilot study to investigate whether giving low-income mothers a small or large monthly sum of cash impacts the cognitive development of their children in the first three years of life. She plans to recruit 1,000 low-income mothers from around the country, half of whom would receive $333 a month, while the other half would receive $20 a month for three years. That research is expected to take five years.

Strikingly, the Steveosphere is given a chance to sound off on this study:

But James Thompson, a psychologist at University College London, has a third theory.

“People who have less ability and marry people with less ability have children who, on balance, on average, have less ability,” he said. Thompson noted that there is a genetic component to intelligence that Noble and Sowell failed to consider.

“It makes my jaw drop that we’ve known for years intelligence is inheritable and scientists are beginning to track down exactly how it happens,” Thompson said. “The well-known genetic hypothesis has not even had a chance to enter the door in this discussion.”

Charles Murray, a conservative political scientist who argues there is a relationship between intelligence and economic class in his book “The Bell Curve,” said genetics cannot be ignored.

“It is confidently known that brain size is correlated with IQ, IQ measured in childhood is correlated with income as an adult, and parental IQ is correlated with children’s IQ,” Murray wrote in an e-mail. “I would be astonished if children’s brain size were NOT correlated with parental income. How could it be otherwise?” …

Good question.

Allow me to point out that a national newspaper has asked a couple of guys who know what they are talking about to punch holes in the latest bit of goodthink and, as of press time, the American public hasn’t dug up Hitler’s DNA and elected it President. So maybe we’re actually mature enough to discuss reality rather than lie all the time?

… The Obama administration has increasingly promoted the idea that the country should provide early childhood education for low-income 3- and 4-year-olds to give them a boost before they get to kindergarten. Last week, Education Secretary Arne Duncan said if he had one more federal dollar to spend on education, he would funnel it to early childhood.

Six decades from now, the Education Secretary of the hereditary Bush-Clinton Administration will be declaring the key periods for federal intervention are the eight months and 29 days before birth … but not a day sooner!