Verbal and Non-Verbal Intelligence Changes in the Teenage Brain

Sue Ramsden et al., Nature, October 19, 2011

Intelligence quotient (IQ) is a standardized measure of human intellectual capacity that takes into account a wide range of cognitive skills1. IQ is generally considered to be stable across the lifespan, with scores at one time point used to predict educational achievement and employment prospects in later years1. Neuroimaging allows us to test whether unexpected longitudinal fluctuations in measured IQ are related to brain development. Here we show that verbal and non-verbal IQ can rise or fall in the teenage years, with these changes in performance validated by their close correlation with changes in local brain structure. 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. By using longitudinal assessments of the same individuals, we obviated the many sources of variation in brain structure that confound cross-sectional studies. This allowed us to dissociate neural markers for the two types of IQ and to show that general verbal and non-verbal abilities are closely linked to the sensorimotor skills involved in learning. More generally, our results emphasize the possibility that an individual’s intellectual capacity relative to their peers can decrease or increase in the teenage years. This would be encouraging to those whose intellectual potential may improve, and would be a warning that early achievers may not maintain their potential.

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  • Bardon

    Since I’ve been skeptical about IQ, I’ll say a few things

    1. intelligence is just one among mental “structures”. I disbelieve there is anything like G, general intelligence, but I’m convinced that there are numerous intelligences/capabilities- spatial, algorithmic, verbal,sensory, musical, “rational” (synthetic-analytic, “philosophical”, not to be confused with mathematical and logical- I’ve known a few brilliant mathematicians who were plain dumb about most elementary things & incapable of following rational arguments which were, so to speak, “non-linear” ).

    2. as for social or emotional “intelligences”- I think it’s a wrong label. These are other psychological traits.

    3. other mental faculties, like imagination,frequently play much more important role than intelligence- defined as you wish. Also, emotional intensity, motivation, focus and absorption in a subject can be crucial.

    4. the summit is psychological maturity, fearlessness, spiritual freedom & independence on dogmas- all traits much more important than IQ triangles & arithmetic sequences. Beethoven couldn’t learn, all his life, how to multiply numbers- he just managed to add them. Poincare, one among greatest mathematical minds in history, also didn’t think much of the nascent field of IQ measurement, and some of his insights on human achievement are still fresh: http://goo.gl/k2e6c

  • Anonymous

    I did my masters thesis on IQ.

    What this article is not telling you is that IQ is not able to measure intelligence (g) directly, at all. The tests do two things well. They separate out normal people from retarded people and possibly identify gifted people (this is in doubt). That is exactly what the tests were designed to do…..identify mental defectives for the purpose of not wasting valuable money and resources trying to educate people who cannot benefit from education. It is very good at doing this.

    The second thing is does is identify brain injury. A persons IQ score doesn’t normally change. If a person say, hits their head and IQ is taken and is now lower than it was before, this is good evidence of diffuse brain injury (something otherwise difficult to detect). That would be largely worthless (IQ testing is no longer standard among students because it correctly identifies almost all blacks as not educable). Fortunately, there are tests with high correlation to IQ that are unaffected by diffuse brain injury. After an injury, if person tests with an IQ of 75, yet they test on the NART-r as if they had 110 IQ and are college educated….that’s strong evidence of diffuse brain injury, even though you probably don’t have a baseline IQ prior to the injury.

    One thing IQ does NOT do. It cannot separate out college material people from geniuses. High IQ is meaningless (and this fact is covered up to a large extent).

    Obviously, the writer of this article does not know that. Probably a statistical artifact anyway, IQ going up and down across age groups says NOTHING about intelligence. The tests are gross measures, not fine ones.

    Further, there is an inappropriate correlation made to activity of certain parts of the brain. Intelligence is a diffuse construct. Someone who is good at waggling their fingers is no more likely to be intelligent than anyone else. And neuroscientists would drool at the possibility of seeing fine verbal skills increase as activity in the language center increases. Such is not the case, however. It just doesn’t work that way.

  • Joe’s Lounge

    Thanks to the commenters at 1 & 2 for their insights. There is a lot of discussion of HBD and IQ in the blogosphere by people who don’t really know what they’re talking about. Posters on HBD blogs cling to their 130+ IQ scores as if they really mark them as superior people.

    I suspect that commenter #2 is right and the main use for IQ tests is to sort out people who are too dumb for college. I’d like to hear more from commenters like him/her who have studied the field.

  • Bardon

    I would like more tests & measurements about psychological profiles, values, big five in PEN model etc. IQ tests are sometimes useful, but race-related issues are not going to be satisfactorily answered by them. Being “slow”, dumb,..call it how you like- doesn’t answer why animalistic malevolent “flash mobs”, why mental & emotional shallowness, why aversion to learning even basic skills that would enable a person a decent living, why obsession with sex, why ..

    Dumb people can be socially useful & lead happy lives. But, in case of Blacks: aggression, envy, parasitism, inability to emphatize, unwillingness (inability ?) to learn standard language, no “higher” aspirations, no true family responsibility … Singing, dancing, running and jumping. That covers their entire life project. Aristotle said that to seek to expand knowledge was an innate human characteristics.

    Evidently, he was wrong.

  • Buridan

    To #1 Bardon.

    .1° It seems to me : There is not really to believe or disbelieve that there is G : among the six capabilities which IQ measure, there is a relatively strong correlation. The guy who is brilliant in moving objects in space, he is often good in logic, too, as the man who is brilliant in sprint, he is often good at long running. That correlation, we calculate it and we name it G.

    Of course, sometimes it is meaningless out of being an average : we have your brillant mathematician who is dumb out of his maths. But the fact is : the more gifted a guy is in maths, the more probable it is that he has many other IQ gifts. We name that correlation G, knowing that it is a general correlation, falsified in some individual cases. But, in fact, it is a relatively strong correlation, which make us talk of some persons as intelligent ones, as we speak of some persons as athletic ones (and it is only rare that we specify : this guy is very good at maths but without any talent to argue, or this man is very good at sprint but very weak at 5 000 m).

    .2° As regards “musical intelligence”, to name intelligence the talent for music is to distort the usual meanning of the word. Nevertheless it could be justified if there were a correlation between IQ and talent for music. I haven’t found any litterature on that point, which interest me. I am relatively skeptical.

    To #2 Anonymous.

    .1° You are not very precise. At which level do you say that the difference in IQ is not significant ? 115 ? 130 ? 145 ? More ?

    .2° I have never heard of that in the litterature, for instance from Arthur Jensen.

    .3° The notion of “genius” is vague. But, of course, one understands that the best man on an intellectual discipline can have an IQ which is not extraordinary, because, as I said above, the correlation between the different components of the IQ is not absolute : it is just a correlation, observed in general. An example is Garri Kasparov, whose IQ is about 120-125. But I would not say that Kasparov is as intelligent as a man with an IQ of 145. I would say that what the IQ measures corresponds to what we call intelligence, and that this chess-genius is not exceptionnally intelligent (as this world-champion X at tennis is not exceptionnally athletic (despite the correlations between chess talent and IQ, and tennis talent and athletic gifts)).

  • Bon, From the Land of Babble

    I suspect that commenter #2 is right and the main use for IQ tests is to sort out people who are too dumb for college.

    The US military may appear to be PC but has been giving IQ tests for 90 years; since WWII, it has invested heavily in IQ testing for all potential recruits. Why? Because IQ correlates with performance, and the military knows it.

    Or as Steve Sailer puts it: The military wants to sort out which recruits can repair its jet engines and other high tech equipment and which recruits are more likely to cause problems and shoot themselves in the foot.

    The U.S. military—remains utterly devoted to the value of cognitive tests. The Department of Defense says ‘AFQT scores are the primary measure of recruit potential.’

    What’s interesting here is how much more the Army values IQ over a high school diploma:

    high-school dropouts tend to drop out of the military, too. The National Priorities Project cites Army studies finding that 80 percent of high-school graduates finish their first terms of enlistment in the Army compared with only about half of those with a General Equivalency Degree or no diploma.

    Don’t think the military and government don’t understand this, they do, and well.

    a dumber army is a weaker army. A study by the RAND Corporation, commissioned by the Pentagon and published in 2005, evaluated several factors that affect military performance, experience, training, aptitude,and found that aptitude is key. This was true even of basic combat skills, such as shooting straight. Replacing a tank gunner who had scored Category IV (on the ASVAB) with one who’d scored Category IIIA (in the 50th to 64th percentile) improved the chances of hitting a target by 34 percent.

    IQ tests have been banned in the schools because IQ scores fall along racial lines as shown by Murray and Herrnstein in The Bell Curve.

    I wish the schools WOULD use IQ to sort out students instead of throwing all and sundry into one class and expect teachers to educate each one up or down to some arbitrary standard.

    To even mention that IQ exists, let alone racial IQ differences, is to commit heresy against educational dogma that states that IQ does not exist — and could end one’s career. Yes, it is THAT serious.

    Easier to blame teachers, White oppression, poverty, and spend trillions of dollars upholding the “IQ does not exist” lie than admit blacks and hispanics have lower aptitudes than Whites/Asians.

    The military knows that in life or death situations, IQ matters.

    Bon

    Did the violent denunciations of the book that was, after all, based on the military’s test cause it to, well, rethink its use of IQ testing?

  • John Engelman

    Colleges can waive IQ tests because they do not pay students; the students pay them. If a college admits a black student with a lower IQ instead of a white student with a higher IQ, the white student loses. The black student loses because he falls behind and eventually drops out. The school takes the black student’s tuition money to the bank.

    Employers in the private sector may pay lip service to affirmative action, inclusion, and diversity. Nevertheless, they know IQ matters, and that if they do not hire the most intelligent job candidates, their competitors will. That is why they increasingly depend on mental aptitude tests when making hiring decisions.

  • Jesse

    to #1 – Bardon

    You are talking abuot Howard Gardners theory of multiple intelligences.

    http://en.wikipedia.org/wiki/Theory_of_multiple_intelligences

    It was a nice little theory, that got a lot of attention, since that would “explain” why some people got low on IQ tests, since IQ tests only measured the logical and mathematical intelligences and not the others.

    Therefore, someone could be intelligent but still get a low score on IQ-tests.

    So everyone could feel good about themselves, getting bad results on IQ just meant that you were good at something else.

    Unfortunately, there is no empirical evidence to support that theory. It’s quite simply made up nonsense without any scientific value.

    Intelligence experts have time and again come to the conclusion that it is the g-factor theory that is the correct one. G for general intelligence, that there is a form of absolute intelligence, which goes for all things. But it is a bit hard to measure, and IQ-tests goes a long way, but doesn’t fully do it. Heavily g-loaded tests are considered more valuable for this purpose.

    This general intelligence decides our ability to learn and to solve problems, but that does not mean that someone with a high intelligence knows everything.

    Just that you have the ability to learn advanced things, doesn’t mean that you will. If you have no interest in learning math, then you won’t learn math, you’ll get bored of it and your mind will wander.

    So what your actual skills and knowledge is, depends more on your personality, than your intelligence.

    If you have a high intelligence you have the ability to learn, if you really want to.

    With a low intelligence, it doesn’t matter how much you want to learn something, you still might not be able to.

  • Anonymous

    Over the last eight years or so, and increasingly since the 60’s, media reports about how IQ can be boosted and about how IQ is not appreciably shaped by genetic influences appear periodically, somewhat like Big Foot sightings. In prosaic efforts at research replication, the “findings” wash out. In prosaic efforts to replicate the findings in actual classroom undertakings, the wind goes out of the sails. But this meta-story is not reported by the media. Nor, for that matter, in undergrad psychology courses on most campuses.

  • Bardon

    # 8

    I don’t think that Gardner’s (or others’) theories have been disproved (one can do with correlations many things, I for one know this from particle physics phenomenology).

    First- I simply don’t believe in G as defined. Although his motivation in denying the existence of such a variable were different from mine-actually, I don’t have any- IMO, Stephen Jay Gould was right in his “Mismeasure of Man” (at least, in G denial interpreted as some cover term for overall human intelligence we all refer in informal talk).

    I do not question the consistency of research & best intentions of psychometricians who in more than 100 yrs devised ingenious problems. Also, I won’t nitpick- only an ET could devise impartial IQ test (just let it go).

    Simply, not only my everyday experience, but much more, teaches me that a person may be verbally acute, with enormous vocabulary and plasticity of expression & still be virtually helpless in maths, life- altering choices, spatial orientation (reminds me of Leon Trotsky, leader of the Red Army, who confessed he “suffered” form “topographic idiotism”). Also, my friends who are academic painters are – IMO- not an intelligent bunch (some of them scored low in IQ tests), but their success & creativity are beyond question. Generally, people tend to be one-dimensional.

    More- this is only one of psychological functions: one might add, in a more traditional lingo- emotions, will, imagination, self-assertion, pride (thymos in Plato), memory, intuition,..

    There is no gulf between traditional psychologies (Plato, Aristotle, Thomas Aquinas, Leibniz, Locke, …) and newer, more empirical psychometrics.

    In short:

    * IQ tests are consistent

    * behind them lies an interpretation that tries to identify results of the more or less pedestrian tests with human intelligence, which carries along with it layers of meaning these tests do not cover and perhaps reverberations of older, religiously inspired thinking (intellect is from gods; intelligence is divine; intelligence is the key to human fulfillment & achievement). I do not subscribe to this interpretation that gives intelligence exalted status it has inherited from our irrational past.

    *as far as predictor for “success in life” goes, it is axiologically questionable- what is success ? IMO- focus, will, energy, emotional investment, motivation,.. are far more important. Richard Feynman, one of the 15-20 greatest physicists of the 20th century, has had IQ measured to be 125. Fine, but completely incommensurable with his achievement.

    * psychometry is a good thing, but hardly more scientific than psychological typology.

  • Buridan

    to #8 – Jesse.

    I appreciate your refutation of Gardner the sayer of gentle nice fairy tales for loving parents of relatively low IQ children, but it seems to me that you go to far on the affirmation of the reality of G (on the “reification” of G, to speak like Stephen Gould the Liar). It exists, people who are very good at a component of the IQ test, and who are weak or mean at another component, as it exists, people who have talent for maths but cannot handle ideas.

    Genetically, there are certainly many genes implicated in intelligence (possibly one third of all our genes, have I read), with some more strategic than others, and that is very coherent with G as a correlation of the different components of the IQ test (these components themselves being nothing more than very strong correlations (for instance there are different capacities in the memory component of the IQ, but strongly correlated)). Here again the comparison with the athletic abilities is very expressive. There are very general features who make someone tendentially good at sprint and, simultaneously, good on long distances too. And there are less general features who make him good at sprint, or good at long running. You argue as if you ignored these less general features. Another example : at sixty a man is less good on every athletic discipline than at twenty. This is an equivalent of G. But maybe he has lost more on long running than he has lost on weight-throwing : that shows that G is not all. Imagine that G comes from the speed of the neurotransmitters. And imagine that spatial intelligence comes specifically from the development of a certain area in the brain, and verbal intelligence from the development of another area. And imagine that there is a correlation between the development of theses two areas : G again. So G is different general features, probably correlated, and the correlation between less general features, and the correlation of these less general features with some general features.

    These correlations being mostly natural, but possibly partly due to mating, too : because clever men seduce beautiful girls, intelligent persons tend to be beautiful, even if, genetically speaking, intelligence has nothing to do with beauty. All the same, one can believe that, intelligent persons tending to marry intelligent persons, that probably contributes to increase G versus non-G (if C is the correlation between intelligence and beauty, the passing of time in a meritocratic society tends to increase C). That tendency being at odds with the fact that engineers tend to marry engineers, businessmen marry businesswomen, etc. All that to say that G is a complex evolving result of many things, and is not all in intelligence. And, to use a vague term : intelligence can be said to be a dialectic of G and non-G.

  • Buridan

    To #1 Bardon.

    Of course, as you say, intelligence is something desirable but there are many other qualities which are desirable. The error, I would say, is to name them intelligence. Let’s not call “intellectual fearlessness” intelligence, as precious as it is. That obscures the discussion. And that is, ultimately, the expression of a submission to the fascination for intelligence.

    A relatively intellectual quality which is not intelligence but which is very important could be named wiseness. There are clever persons who are always wrong, brilliantly wrong. That quality itself has different components or origins… It is not evaluated in education, and cannot be tested in tests of the kind of the IQ one. But succesful professionals no doubt often possess this quality. Napoleon used to ask of an officer to be promoted “Is he lucky ?” (“A-t-il de la chance ?”), so “Has he got unjustified successes”, so “Has he got successes which are probably due to good judgments who could not be demonstrated as good judgments at the time, but probably were, hence the success?”.

  • Stick

    At the high school I went to (in Australia) we all had to do an IQ test. The lowest IQ we had in my year was 107. There were 4 asians, 1 Australian aboriginal and the other 155 were white. (It was a state selective school – that means only smart kids were picked to go there).

  • White Guy In Japan

    #8-Jensen spoke of Gardner’s theory and said that while it could be useful, there was not enough evidence currently. Personally, while I can see the value in identifying different areas of skill, I can see the potential for a lot of cheap excuses.

    Anyway, here’s a book-length interview with Jensen:

    http://goo.gl/bxPRB

  • Anonymous

    “I suspect that commenter #2 is right and the main use for IQ tests is to sort out people who are too dumb for college. I’d like to hear more from commenters like him/her who have studied the field.”

    The French national school department more than 100 years ago decided that it was important to test 4 to 6 year olds to determine if they were capable of learning in classes designed for children of normal intelligence.

    The thinking was why should the low, below 90 IQ kids not be noticed unitl 4th grade or so when it was obvious they were retarded. Find them early, when they started school and send them to classes designed for IQs in the 90 to 65 range. Give them what they needed from the start.

    Benet was the man who developed the first test. The French school system began giving the test the first month of the first year. The retarded students went to special classes. It was a good system.

    The French never intended it to be used for lycee and college admission. That was already covered by the centuries old exam system.

    Poster 2 is right. It is still a good idea. That way parents and teacher’s of 75 IQ children won’t be sidetracked by nonsense about learning disabilities, attention deficit, different learning modalities blah blah blah.

    It is not a bad idea to have your children’s IQs tested when they are 6 or 7. That way 2 Drs will not be pushing a 105 IQ to take lots of advanced placement science courses to get into med school. If your child’s IQ is below 90, you will never be told that the child is dumb. You will get a lot of learning disability, extra homework, teach the child at home after a long day’s work nonsense.

  • Anonymous

    “Employers in the private sector may pay lip service to affirmative action, inclusion, and diversity. Nevertheless, they know IQ matters, and that if they do not hire the most intelligent job candidates, their competitors will.

    That is why they increasingly depend on mental aptitude tests when making hiring decisions. ”

    John, those written tests were abolished 50 years ago in all sectors. Even computer programmers are not tested on their knowledge anymore. If their resume checks out and they have their Oracle certificate or whatever they get the job.

    Teachers, nurses, Drs, programmers, engineers, barbers and many others do need a certificate to get a job. The employees don’t bother testing people with a professional certificate.

    Those aptitude tests were for hiring people with no experience for entry level jobs. The tests were designed to see if applicants had a reasonable IQ and most important were fast learners.Could a carpenter add and subtract fractions.

    One thing about those tests. Answers to the last 1/3 of the test often depended on questions and answers in the first part of the test. The idea was that fast learners would pick up clues to the right answers in the last part of the test from the logical answers to the first questions.

    Those tests had a lot of “what would you do if” questions. Those tests were appropriate for people with no experience.

    Now that dozens of people with 10 years experience in the exact same job apply for jobs, employers no longer give tests.

    General tests, like 12 grade reading skills are forbidden because of affirmative action. So is the requirement that a carpenter be able to measure and add and subtract fractions.

    As far as employers in the private sector, have you walked past a construction site in the last 30 years? Been to a hotel or restaurant? Do you think any of those illegal alien Indians passed any kind of test? Been to a Dr office or hospital and seen who works there?

    Really John.

  • Anonymous

    7 — John Engelman wrote at 12:35 PM on October 21:

    “Employers in the private sector may pay lip service to affirmative action, inclusion, and diversity. Nevertheless, they know IQ matters, and that if they do not hire the most intelligent job candidates, their competitors will. That is why they increasingly depend on mental aptitude tests when making hiring decisions.”

    Englemann, if you know of just one employer that gives mental aptitude tests please let us know. My husband is a highly paid computer systems designer. He has worked for Lufthansa, Sperry Rand and now works for Microsoft. He has never taken a mental aptitude test for employment. Neither have I. I am a nurse practicioner. I have followed him around the country. I have never taken any mental aptitude test for my several jobs. I don’t think any friends or relatives have either.

  • convairXF92

    to #17: I think Mr. Engleman refers to the “how would you move Mt. Fuji” puzzle question sets (famously used by Microsoft, Google, and Wall Street) rather than anything like Stanford-Binet. Though, I once got hit with a real IQ test–perhaps in violation of the law–when applying for an electronic design/debugging job, in 1999 I think.

  • Buridan

    #17 Anonymous.

    In two former recent mails you have refered to you as a man, here you talk of your husband, in a former mail you have said that you reside in California, in another one that you live in Frankfurt/am/Main (Germany). So, the credibility of your assertions is in doubt for me.

    I have been a computer programmer in France. To be taught computer programming I have been selected by the private school (belonging to Control Data Corporation) exclusively by an IQ test, and I have been selected in my job by another IQ test (and by a personnality test, and by an interview, of course).

  • Fr. John+

    IF IQ fluctuates during the teenage years, it’s only another reason to cheer non-white dropout rates in high school.

    Who really cares about all this, any more?

    After 400 YEARS, can we not see that non-Whites will NEVER be our Equals?

  • Anonymous

    #16: When I applied for a job at a grocery store as a teenager, they gave me a series of tests during the interview. In one test, they had a booklet of many pages of pictures of product (milk, bread, etc.). I had to fill in the correct price next to each picture from a reference sheet, and they timed the test. Of course, this is a test of memory: almost anyone can systematically copy prices, but to do it quickly, one needs to be able to quickly memorize the prices for the various products.

    In the second, I had to assemble a number of irregularly-shaped blocks into a square. It was supposed to test whether I could pack a shopping bag with groceries. I now recognize it as a test of spatial reasoning.

    A few years later in college, reading about IQ testing, I realized this employer had basically been hiring partially based off of IQ tests hidden as jobs-skills tests. I understand why it’s illegal — disparate impact again and we all know we’re all really equal, except those horrible racists — but it’s also obvious why the employer wanted to do this. I only worked there for 3 months over the summer and did a smattering of everything in the store. How much time and effort do they want to spend training someone (a kid) who is not likely to be around long-term? Hire someone above a minimum IQ cutoff (= is likely able to learn quickly), explain/show the job once, and the person is productive.