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
musicians (Mind-expanding
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".