Scans suggest IQ scores reflect brain structure
Research results reignite intelligence controversy.
Researchers say that a remarkable data set on the developing brain adds to the idea that IQ is a meaningful concept in neuroscience. The study, which is published on page 676 of this issue, suggests that performance in IQ tests is associated with changes in the brain during adolescence.
Read the story here.

Comments
This interesting study does not indicate that IQ is intelligence per se. It shows that what IQ tests is reflected in the brain. Such details are of interest to those of us who study neural development but they do not illuminate the IQ controversy one way or other. Everything is reflected in the brain.
The IQ controversy is really over how much the environment influences IQ. These data do not speak to this.
Posted by: Janice M. Juraska | March 30, 2006 07:19 PM
The highest correlations to IQ are vocabulary and general information levels. The greater thickening of the prefrontal cortex may indicate a period more intensive comprehension neuronal activity regarding readings, discussions, interests, etc. The parents' level of education and adult level of cognitive interaction is needed, as well as the amount and content of TV viewing, home schooling, physical activity/sports, etc.
The brain development cycles through stages of stimulation and growth from interesting and varied environmental stimuli (construction stage), followed by pruning (operation stage). The brain adapts to the environment whether enriched or deprived and a period of intense enriched construction would be followed by pruning that would still leave an enriched network of synapses to operate in a more complex environment. For the prefrontal cortex, growth and construction would be promoted by exposure to adult and progressive developmental models of thinking, analysis, definition, vocabulary concepts, comprehension and information in context of personal interests and linking to prior knowledge. We need to know more retrospectively about the family backgrounds, environments and explorations of these individuals. Please continue the study with these subjects over the next 20 years.
Posted by: Lyelle Palmer, Ph.D. | March 31, 2006 01:19 PM
Why use "IQ" as a measure of "intelligence" ? IQ is basically an attempt to rescue the statistically flawed Binet-Simon "âge mental" concept, via the erroneous postulate that the quotient "mental age / real age" remains constant during childhood, and the Terman (1917) pragmatic, but scientifically unambitious, reworking. On the opposite, the Spearman "g factor" concept is a statiscally sound approach to the "how to measure intelligence" problem (and, incidentally, far less sensitive to environmental factors than IQ is). Why not use it in research like the one reviewed by Nicola Jones ?
Posted by: Jean-François Foncin | April 4, 2006 02:12 PM
Mr. Foncin, even the use of Spearman's g (or what g is a statistical indicator of) as a measure of "intelligence" is problematic since some executive functions do not correlate with the general factor. Additionally, Flynn's Effect poses a prima facie challenge to using g as a measure of intelligence. Yes g seems on more secure footing (qua psychological construct), but remember that you reliably get g only by extracting it (via factor analysis) from a correlation matrix of performance on a large battery of diverse mental ability (i.e., IQ) tests given to a large sample of people. Lastly, the most popular IQ tests are the WAIS and WISC, neither of which use the old Binet-ian "age mental" concept (though they are age-group norm based); moreover, the only way to get someone's g-score is by administering a highly g-loaded test (such as Raven's Progressive Matrices or the two aforementioned IQ tests).
Posted by: S. Brian Hood | April 5, 2006 05:40 PM
[Sorry if I don't use my real name on the internet, but that's not my habit.]
The last sentences of the article are normative rather than objective. Mr Rose has nothing to do with this research.
Posted by: dmc | April 21, 2006 09:07 PM
I hope this kind of research continues. I am not a scientist and I cannot "prove" some things I have observed or "suspected". I believe I have seen a correlation between intelligence and pigmentation in some cases. Of course, I've been railed at by two siblings who think I am very ignorant. This kind of research into how the brain functions and the socioeconomic implications of that is very needed. Thanks.
Posted by: M M Lytle | May 9, 2006 04:28 PM