You may have heard about the intriguing findings of this recent study published in Nature that show that IQ scores among teenagers are quite variable over time and, moreover, that these changes in IQ are related to changes in the physical structure of the brain. That’s right! For many years it was assumed that intelligence, as measured by IQ tests, was fairly set for life. It was thought that IQ scores from testing conducted in childhood were pretty good predictors of future cognitive function, and even of future academic success and earning potential.

Well, researchers at University College London conducting a study of 33 adolescents aged 12 – 16 found fluctuations in IQ scores in individuals of up to 20 points over 4 years. And these changes weren’t random. Brain scans showed that the changes were proportional to actual structural changes in the brain. What is really intriguing though is that we know what activities seem to cause these developmental changes in the brain.  While it was not the goal of this study to pinpoint all the myriad factors that can affect cognitive function it does point up some tantalizing clues. According to the report, “A combination of structural and functional imaging showed that verbal IQ changed with grey matter in a region that was activated by speech, whereas non-verbal IQ changed with grey matter in a region that was activated by finger movements.” Specifically, for example, the act of speaking causes a structural change in the left motor cortex of the brain. This change in turn correlates with an increase in verbal IQ score. So, development of brain structure is clearly linked to cognitive function, and these developments are triggered by practice at things we can control. It would seem then that given this understanding parents and educators could better target activities that are linked to increasing cognitive function.

This relationship between practice and cognitive development calls to mind the research of paleoanthropologist Peter McAllister. In his entertaining book Manthropology, McAllister compares the achievements of modern men with those of their ancient forbears only to demonstrate modern man’s relatively feeble performance even in such intellectual pursuits as verbal creativity (as demonstrated through a comparison of the achievements of Homer and other ancients with those of modern rappers). Here, as throughout the book, McAllister attributes the dismal disparities to ontogenetic causes, in other words, in most cases, simply to practice.

This conclusion would seem to be supported by the assertions of our old friend, cognitive scientist Daniel Willingham. In this article Willingham distinguishes between rote knowledge, which is sort of mindless parroting, practically devoid of meaning and inflexible knowledge which is characterized by shallow or superficial meaning. Most students readily acquire this kind of inflexible knowledge rather than just the rote knowledge that conscientious teachers shun and dread. And that’s not a bad thing. Willingham explains that we achieve expertise by first accumulating inflexible knowledge and then applying it in a variety of contexts through practice. This would seem to corroborate the study’s findings and provide insight to educators; practice with manipulation of facts and ideas, verbally and kinesthetically, in a variety of contexts can lead to deep knowledge and quite possibly to measurable gains in cognitive function. All of which brings us back to last week’s post about the secret of success being persistence.