Is IQ Trainable?
From my perspective, one of
the most interesting articles in today's news is the announcement that the
hippocampal regions of the brains of London taxicab drivers (Taxi
drivers' brains 'grow' on the job expand
measurably as they learn the city's topology. Combining this with our gathering
knowledge of the brain's plasticity, and the fact that similar enhancements of
musically-relevant areas of the brain seem to be occurring in the brains of
tunes and you have indications that, like
muscles, the brain may be modified with use. This squares with studies that
show that racetrack bookmakers can calculate odds that they should be
constitutionally incapable of generating, and that others can perform mental
functions important to their day-to-day activities that would be expected to
lie beyond thier innate capacities. Finally, these results are consistent with
Flynn and Dickens' ideas about the mechanism that underpins the Flynn Effect.
They're also consistent with the observation that there were structural
anomolies--"math bumps"-- in the craniums of Gauss and Dirichlet, and
extra glial cells in Einstein's brain. The presumption has probably been that
these irregularities were inborn, but perhaps it will transpire that they were
generated through ceaseless mental exercise.
There have been many attempts to create "superkids" over the years. I think that some of them may have been successful. The conventional wisdom is that children like John Stuart Mill, Billy Sidis, Norbert Wiener, etc., had exceedingly good genes and just happened to be the sons of fathers who pushed their children. Supposedly, there are hundreds of thousands of other fathers who also pushed their children, but whose children lacked the genetic endowment to respond*. What are the odds that Boris and Sarah Sidis would set about to create the (perhaps) smartest child in history,and to actually produce the (possibly) smartest child in history not because of anything they did or didn't do, but because of their genetic legacy? And if that seems acceptable to you, how about Norbert Wiener and John Stuart Mill? But the problem with this is that we need more than hundreds of thousands... we need millions. In the case of William Sidis, if estimates of his intelligence are even remotely correct, he's impossible. His adult (ratio) IQ has been estimated at 250 to 300. The highest IQ that could be expected in the United States would be something like a ratio IQ of about 230 to 240, corresponding to a deviation IQ of 190 to 193. If we find any IQ's over that, then (I should think) we have to begin to reevaluate our concepts of inherited IQ. In other words, among children, ratio IQ's above 240 would seem to me to be a sign that other mechanisms are at work besides pure inheritance. And Of course, spurts in rates of mental development and childhood stimulation that will temporarily boost IQ might also distort childhood test scores. However, that wouldn't account for adult ratio IQ scores above the 230 to 240 level (deviation IQ of 190 to 193). William Sidis' adult IQ has been estimated by Abraham Sperling, the Director of New York City's Aptitude Testing Institute, at "250 to 300". Note that this would have been a ratio IQ, since deviation IQ's were undefined in the 40's. (Note also that Leta Hollingsworth searched for years in New York City and elsewhere to find her 12 children above 180 IQ.) It's conceivable that Dr. Sperling might not have encountered other individuals in that range. Dr. Sperling evaluated William's record after William's death. But it's also clear that he concluded that William was head and shoulders above the 5,000 individuals whom Dr. Sperling had tested. An adult ratio IQ of 240 falls at the upper bound of the range of expected log-normally-distributed IQ's in the United States. If William Sidis had an adult IQ much above this value, then I should think that this would argue in favor of James Flynn and William Dickens' recent model that underscores the role of mental exercise enhancing the mind.
The bottom line? I suspect these guys succeeded, albeit at great emotional cost to their sons, but in the emotionally charged stampede to discourage such parental interventions in children's lives, a very important chapter in the heredity-versus-environment debates may have been unscientifically expunged. Now it's time to revisit this topic.
And yet... and yet, there's the story of Y Y was adopted shortly after birth. His foster-arents must have been taken aback when he began to pick letters off billboards at 9 months. His parents bent over backward to be sure that they didn't push him because of all the ugly stories of what has become of child prodigies who were pushed by their parents. By 15 months, he was reading, and was reading French at 3. It's hard to attribute such a happening to anything other than genetically-conferred intelligence. This would seem to be a case of "genius will out".
I realize that a great deal of meticulous psychometric research supports current concepts of IQ and of g.
* - One such case may have been that of Nona Toops, the daughter of Ohio State psychologist, Dr. Herbert Toops. Legend had it among the graduate students in psychology that Dr. Toops had set about to rear a supersmart child in Nona, but that Nona wanted to fit in socially with the world. I met Nona once or twice in the Ohio State Student Union. She seemed like a very pleasant, normal, pretty lady.
Since we now know that infants are born with many more neurons than they will ultimately retain, and since we also suspect that areas of the brain can be expanded through continual "stretching", there's a theoretical basis for the idea that it might be possible to increase intelligence with effort over time. At the same time, the retarded must have been the recipients of some intense, presumably-unsuccessful interventions aimed at boosting their brainpower.
The Milwaukee Project was operated from 1966 to 1973 with 17 children born into inner-city environments to mothers whose IQ's were 75 or below, plus 18 similar children who were used as controls. The founder and director of the program once quipped that compared to the cognitive development regimen provided in the Milwaukee Project's Stimulation Center, the childhood environments of such famous prodigies as John Stuart Mill and Sir Francis Galton appear educationally deprived. The treatment program ended when the children entered first grade at age 6. At that time, the average IQ difference between the two groups was 32 points, with an average IQ in the 17-child test arm of about 119, compared to an average IQ in the 18-child control arm of 87. However, the scholastic aptitude and achievement test averages of the test group were barely superior to those of the control group, and soon reached parity with it. After a few years, both groups performed at an IQ level of about 80 in the actual classroom environment, and on scholastic achievement tests. The researchers' conclusion was that they had been "teaching to the test", and that the gains were illusory rather than real. (Dickens and Flynn are now suggesting that perhaps social factors and removal of the children from their stimulating early environment may have been the reason their gains didn't become more meaningful and more durable.)
A similar study was conducted in the form of the Abecedarian Early Intervention Project at the University of North Carolina in 1972. The average IQ of the mothers was 84. The program lasted for five years. This program seems to have been more effective, with a seemingly meaningful IQ difference of about 5 points at the age of 15. This 5-point IQ differential was accompanied by corresponding improvements in scholastic achievement on the part of the test group versus the control group.
Still, there are no monumental prodigies springing from these efforts. Of course, it must be remembered that the all-important contributions of parents and home-life that would have occurred in the fostering of a William Sidis or a John Stuart Mill wouldn't have been present in these day-care experiments. Also, they both ended when school began.
It may be that, as in other aspects of inheritance versus environment, there are sizable differences in innate characteristics, and that, given equal effort, some will be much brighter than others, just as, given equal effort, some will be much better baseball pitchers than others. However, athletic skills are more a function of mental and nervous system development than they are of innate athletic capability (recognizing that someone 5' 4" tall probably won't make a good linebacker or pitcher). Perhaps the enormous improvements in athletic performance registered by today's children is indicative of corresponding enormous improvements in the motor centers of their brains. The magnitude of the Flynn Effect demonstrates that the average individual can be a lot brighter than they were in 1880. One "factoid" that has always interested me is the fact that in a study of identical twins separated at or near birth, the greatest disparity in adult IQ was 26 points, between one twin who was a New York City schoolteacher and the other twin, who was an Iowa farmwife.
Two interesting discussions of the characteristics of the gifted are available here. One, "A Study of 241 Profoundly Gifted Children," by Dr. Karen Rogers, summarizes the results of a study of 241 profoundly-gifted children with ratio IQ's ranging from 160 to 237+. The other, by Dr. Linda Silverman, is entitled, "Different Worlds at the Extremes".