The Washington Post did not put this story on page one.
>New research that shows poor children have smaller brains than affluent children has deepened the national debate about ways to narrow the achievement gap.
Most of the story goes with the assumption poverty causes smaller brain size. But amazingly enough, the story also includes this alternative interpretation:
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.”
The story also quotes Charles Murray.
“I would be astonished if children’s brain size were NOT correlated with parental income. How could it be otherwise?”
The politically correct presumption would be that the brain size of poor children can be increased using some government programs. Can we verify that by comparing brain sizes of identical children raised apart? Or by comparing brain sizes of children randomly chosen for pre-school programs with children from a control group?
Murray has more commentary here, including a historical scientific controversy over whether there even exists a relationship between brain size and intelligence among humans.
I kind of get how we partake of useful collective delusions in mass media. I have trouble accepting it in academia.
(With the caveat that brain size would be a poor proxy for intelligence. I would think little would stop an elephant or whale from evolving larger brains. Compactness and architectural efficiency (akin to miniaturizing electronic circuits) and plasticity are possibly better evolutionary correlates with intelligence.)
It’s more about brain size relative to body size, not absolute brain size.
It seems to be about cortical surface area and relative size within species as a proxy for something that might matter like IQ.
Problem is genetics becomes a crutch to explain everything and absolve us from responsibility or initiative, becoming a just so story when variation is at least as important, not that it should be neglected but that separating it from nurture, culture, and the rest is difficult.
Lord’s comment illustrates why the right resists genetic explanations (we already know why the left dislikes them). Butts up against notions of free will and just dessert.
So that’s an experiment which tested a thousand or so American children. It ought to be possible to replicate in rats. More to the point, if there’s actually some connection between children’s brains and their environment, we ought to see interesting results from studies of French and Scandinavian youngsters on the one hand (childhood subsidies) and children raised in North and South Korea. We might also want to examine whether the brain-size gaps become increasing serious as the length of childhood exposure to poverty increases, We ought to have a handle in 4-5 years over whether this is a real effect or hand waving.
And then American liberals and conservatives can spend the rest of the century debating whether the federal government ought to have programs that address the issue.
Rosenzweig, M. R.; Krech, D.; Bennett, E. L.; Diamond, M. C. (1962). “Effects of environmental complexity and training on brain chemistry and anatomy: A replication and extension”. Journal of comparative and physiological psychology 55 (4): 429–437.
It should be possible to do a follow up comparing further down to adopted or natural children, rich and poor. That way you can isolate the genetic component.
Alternatively, look at adopted siblings and twins, similarly to what Bryan Caplan talks about in his book.
Nice
To segue onto a related hobby horse of my own–within twenty or thirty years, it will be generally accepted that Neanderthals were on average more intelligent than modern humans, only less social and less aggressive. Cranial capacity isn’t everything, but it does matter.