Nature Neuroscience | Action Potential

The column that Dr. Watson needed to read

There was a great Op-Ed piece in the NY Times yesterday, written by Dr. Richard Nisbett, that provides a nice set of studies challenging the notion of inherent intelligence differences between races. Dr. Nisbett communicates these findings to the reader in a very clear fashion, providing good information for those of you who followed the news and debate underlying the Watson scandal.


One telling excerpt that I especially appreciated, since it is based on the sheer weight of scientific logic:

That environment can markedly influence I.Q. is demonstrated by the so-called Flynn Effect. James Flynn, a philosopher and I.Q. researcher in New Zealand, has established that in the Western world as a whole, I.Q. increased markedly from 1947 to 2002. In the United States alone, it went up by 18 points. Our genes could not have changed enough over such a brief period to account for the shift; it must have been the result of powerful social factors. And if such factors could produce changes over time for the population as a whole, they could also produce big differences between subpopulations at any given time.

As stated, we know that it is impossible for our genes to change enough in 55 years to account for such vast differences in intelligence (as measured by the IQ test), simply because that time frame spans only 1-2 generations at most! Epic genomic changes do and can occur, but require many generations to take place, events only successfully studied and carried out in organisms with short lifespans and rapid reproductive cycles. But more importantly, doesn’t this simply reinforce the fact that the IQ test suffers from serious bias and unreliability issues? 18 points in 55 years??? Either Sesame Street and Baby Einstein are miracle workers, processed foods and high fructose corn syrup are unfairly ignored as “brain foods”, video games are better than reading, or the IQ test isn’t as accurate as we would like it to be. So let’s be a little cautious when comparing these numbers, especially when pointing out differences…

Why these concepts are so challenging for a significant portion of the population to grasp really boggles my mind. To those individuals, if you don’t have the time or motivation to read The Mismeasure of Man, I certainly hope that you will at least read the “lite” version (meaning this Op-Ed piece [ONLY 2 PAGES!!!]) to assist you in establishing your opinions on this matter. But perhaps even that is asking too much. Therefore, why don’t you wait for the “Op-Cast” to update this week, so you don’t even have to read.

Comments

  1. Report this comment

    Winter said:

    These concepts are challenging because there is so much conflicting verbiage around the issue. Let’s take this very posting for example:

    You highlight Nisbett’s statement: “Our genes could not have changed enough over such a brief period to account for the shift; it must have been the result of powerful social factors.”

    But then you ask rhetorically:

    “But more importantly, doesn’t this simply reinforce the fact that the IQ test suffers from serious bias and unreliability issues?”

    Well, which is it? Nisbett claims that the change is a result of powerful social factors; you seem to be claiming that the test themselves are biased and unreliable.

  2. Report this comment

    Noah Gray said:

    I don’t understand your confusion. The answer is both. Because the test is influenced by powerful social factors, it is biased and unreliable, bringing into question its usefulness. The allusion to the impossibility of that amount of change over that short a period of time was simply to emphasize that the IQ score difference had to occur due to something other than raw genetics.

    The existence of the Flynn effect and the periodic “recalibration” of the average IQ score back to 100 underscores this premise.

    But that’s the funny part about this argument. The proponents of heredibility find racial IQ differences, but these vanish once social factors are properly factored into the debate. So even when using a flawed test for intelligence, we can still find no differences. In my opinion, if you don’t consider social factors when interpreting IQ test results, you might as well be conducting the good old-fashioned test of filling hominid skulls with lead shot or mustard seed to determine intelligence.

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    Drugmonkey said:

    Actually I think changes in the diet might be a good place to start looking for sources of variance, interested in developmental neuroscience as we all are.

    IIRC (it’s been awhile), wasn’t Binet’s whole goal in creating an “IQ” measure to identify those who were underperforming (in school) so that environmental conditions could be changed to bring them up to norm? This would mean the whole concept prioritized the identification of environmental, instead of innate, contributions to cognitive performance.

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    Anonymous Doubter said:

    First of all, I agree with your basic premise: something other than “raw genetics” is at play here.

    But the matter at hand is why do people find it difficult to understand the issues. I still think the way you phrase your remarks hints at the source of confusion that some people have in this area.

    In the article you reference, Nisbett is claiming that the Flynn effect is real; i.e., I.Q. gains have occurred because of environmental differences.

    But you then state:

    “Because the test is influenced by powerful social factors, it is biased and unreliable, bringing into question its usefulness.”

    I imagine that most people think a “biased” test is one where some particular segment of the test group has an inherent advantage because of the nature of the questions themselves. That they are skewing the results in one direction inappropriately. But Nisbett is saying that, no, the Flynn effect is real; there is a measurable difference – not because of inherently genetic difference, but because of environmental factors but the effects are rea.

    Perhaps no test can tease away the inherent, genetically-based intelligence potential from

    the effects of environment (nutritional, social, etc.) but is it right to call the tests “biased and unreliable”? If they are unreliable is the Flynn effect false?

  5. Report this comment

    Drugmonkey said:

    AD, I tend to not like the accusation that standardized tests of cognitive capability are “biased” myself. Trouble is, that the long version of the explanation is…loooong. So in popular use it gets shorthanded to “the test is biased against group X”.

    In some senses it is the experimental design which is always “biased” because it has the subtext of “all other differences (save group status) held constant”. And various studies go to a lot of trouble to parse (by sampling, statistical techniques) the “other differences”. The debate should really be about how accurate those approaches to design are, rather than attacking the nature of a given test if you ask me.

    With the Flynn effect is this really so difficult? Isn’t the classic corn example sufficient? If the amount of water or nutrients in the soil or available sunlight is changed, the average height of the whole plot will change. This doesn’t mean that the difference between plots is “genetic” in origin. There is also no reason to think that the relationships between genetic and environmental determinants of growth are linear, just to head that one off.

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    Action Potential said:

    When it rains…it pours

    I don’t know what it is about Jim Watson and my blog posting, but every time I mention him (as I did in my previous entry), something else pops up and I have to talk about him again. While doing…

  7. Report this comment

    Noah Gray said:

    A fabulous Malcolm Gladwell (The Tipping Point and Blink author) review of James Flynn’s new book What is Intelligence? can be found here.

    For the record, Mr. Gladwell has a mixed racial background.