Poor people have I.Q.’s significantly lower than those of rich people, and the awkward conventional wisdom has been that this is in large part a function of genetics.
After all, a series of studies seemed to indicate that I.Q. is largely inherited. Identical twins raised apart, for example, have I.Q.’s that are remarkably similar. They are even closer on average than those of fraternal twins who grow up together.
If intelligence were deeply encoded in our genes, that would lead to the depressing conclusion that neither schooling nor antipoverty programs can accomplish much. Yet while this view of I.Q. as overwhelmingly inherited has been widely held, the evidence is growing that it is, at a practical level, profoundly wrong. Richard Nisbett, a professor of psychology at the University of Michigan, has just demolished this view in a superb new book, “Intelligence and How to Get It,” which also offers terrific advice for addressing poverty and inequality in America.
Professor Nisbett provides suggestions for transforming your own urchins into geniuses — praise effort more than achievement, teach delayed gratification, limit reprimands and use praise to stimulate curiosity — but focuses on how to raise America’s collective I.Q. That’s important, because while I.Q. doesn’t measure pure intellect — we’re not certain exactly what it does measure — differences do matter, and a higher I.Q. correlates to greater success in life.
Intelligence does seem to be highly inherited in middle-class households, and that’s the reason for the findings of the twins studies: very few impoverished kids were included in those studies. But Eric Turkheimer of the University of Virginia has conducted further research demonstrating that in poor and chaotic households, I.Q. is minimally the result of genetics — because everybody is held back.
“Bad environments suppress children’s I.Q.’s,” Professor Turkheimer said.
One gauge of that is that when poor children are adopted into upper-middle-class households, their I.Q.’s rise by 12 to 18 points, depending on the study. For example, a French study showed that children from poor households adopted into upper-middle-class homes averaged an I.Q. of 107 by one test and 111 by another. Their siblings who were not adopted averaged 95 on both tests.
Another indication of malleability is that I.Q. has risen sharply over time. Indeed, the average I.Q. of a person in 1917 would amount to only 73 on today’s I.Q. test. Half the population of 1917 would be considered mentally retarded by today’s measurements, Professor Nisbett says.
Good schooling correlates particularly closely to higher I.Q.’s. One indication of the importance of school is that children’s I.Q.’s drop or stagnate over the summer months when they are on vacation (particularly for kids whose parents don’t inflict books or summer programs on them).
Professor Nisbett strongly advocates intensive early childhood education because of its proven ability to raise I.Q. and improve long-term outcomes. The Milwaukee Project, for example, took African-American children considered at risk for mental retardation and assigned them randomly either to a control group that received no help or to a group that enjoyed intensive day care and education from 6 months of age until they left to enter first grade.
By age 5, the children in the program averaged an I.Q. of 110, compared with 83 for children in the control group. Even years later in adolescence, those children were still 10 points ahead in I.Q.
Professor Nisbett suggests putting less money into Head Start, which has a mixed record, and more into these intensive childhood programs. He also notes that schools in the Knowledge Is Power Program (better known as KIPP) have tested exceptionally well and favors experiments to see if they can be scaled up.
Another proven intervention is to tell junior-high-school students that I.Q. is expandable, and that their intelligence is something they can help shape. Students exposed to that idea work harder and get better grades. That’s particularly true of girls and math, apparently because some girls assume that they are genetically disadvantaged at numbers; deprived of an excuse for failure, they excel.
“Some of the things that work are very cheap,” Professor Nisbett noted. “Convincing junior-high kids that intelligence is under their control — you could argue that that should be in the junior-high curriculum right now.”
The implication of this new research on intelligence is that the economic-stimulus package should also be an intellectual-stimulus program. By my calculation, if we were to push early childhood education and bolster schools in poor neighborhoods, we just might be able to raise the United States collective I.Q. by as much as one billion points.
That should be a no-brainer.