Bad Environments Supress IQ Children's I.Q.'s

IQ has a large genetic component, particularly within the subset of families who are middle class examined by adoption and twin studies. But, there is evidence that family environment does matter a great deal, particularly among those in poverty.

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,” . . . 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.

The 2008 book "Outliers" also makes a case that something as simple as a child's birthday impacts how that child is tracked amongs students who start school in a specific academic year which has a lifetime impact on educational achievement that is never overcome. This book also suggests that the most important factor may be nothing more complicated than the raw number of hours devoted to a particular kind of activity. Thus, middle class children may excel simply because they have a baseline of far more hours of quasi-academic activity away from school than their poor peers.

An examination of the Flynn Effect (increasing average IQ over time) shows that much of the gains over the years comes from fewer people getting very low scorees, rather than mostly from gains that are even at all raw IQ score levels, which suggests that the removal of adverse environmental impacts (like lead poisoning, poor nutrition and mindless child labor) may be more important than other developments.

The op-ed quoted above hedges on the question of whether parenting or schooling makes much of a difference for kids who live at least middle class lives and receive at least a typical public school education, and the question of how deep poverty must be to matter.

Educational data are suggestive of the idea that while very bad situations reduce academic achievement, and that perhaps a very thin cream of excellent educational options advance academic achievement, that there is a very wide middle ground perhaps the middle 80-90% of educational and socio-economic conditions, in which academic performance seems to be largely indifferent to differences in educational or socio-economic environment. Schools where academic performance depart significantly from the socio-economic backgrounds of the children who attend the school are quite rare, and even fewer schools sustain this departure from expectations based upon the children's roots for many years in a row. The far more usual experience is for "high achieving" schools to coincide with the most socio-economically elite schools, and for changes in a school's academic performance to track demographic change within its student body. But, the very existence of outliers from this prevailing deterministic trend does provide some hope that somebody is doing something right which can be replicated.