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Virtues of Cognitive Workout: New Research Reveals Neurological Underpinnings of Intelligence

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How much does environment influence intelligence? Several years ago University of Virginia Professor Eric Turkheimer demonstrated that growing up in an impoverished and chaotic household suppresses I.Q. – without nurture, innate advantages vanish. What about genes? They matter too. After decades of research most psychologists agree that somewhere between 50% and 80% of intelligence is genetic. After all, numerous studies demonstrate that identical twins raised apart have remarkably similar I.Q.’s.

A 2008 paper out of the University of Michigan turned all of this on its head. The researchers led by Susanne M. Jaeggi and Martin Buschkuehl, now at the University of Maryland, found that participants who engaged in short sessions of “cognitive training” that targeted working memory with a simple but difficult game known as the n-back task boosted a core feature of general intelligence called fluid intelligence. Crystalized intelligence improves with age and experience. Fluid intelligence, in contrast, is the capacity to make insights, solve new problems and perceive new patterns to new situations independent of previous knowledge. For decades researchers believed that fluid intelligence was immutable during adulthood because it was largely determined by genetics. The implication of the 2008 study suggested otherwise: with some cognitive training people could improve fluid intelligence and, therefore, become smarter.

This brings me to a brand new paper recently published in the journal Neuroscience by DRDC Toronto researcher and Adjunct Assistant Professor of Psychology at the University of Toronto-Scarborough, Oshin Vartanian. In the study, Vartanian and his team asked if working memory training improved performance on a test of divergent thinking known as the Alternate Uses Task. Psychological research demonstrates that divergent thinking “loads” on working memory, meaning that when people engage a divergent thinking task their working memory capacity is accessed accordingly. If cognitive training strengthens working memory then participants should improve their performance on divergent thinking tasks. The researchers also wondered how working memory training affected participants at the neurological level. That is, will participation in a short regiment of working memory training be correlated with greater “neural efficiency” during the Alternate Uses Task? Given that divergent thinking is linked to creativity, it also sheds light on the effect of working memory training for boosting creativity.

To answer these questions Vartanian and his team gathered 34 participants and assigned each of them to either an experimental or control group. In the first part of the study the researchers measured fluid intelligence using Raven’s Advanced Progressive Matrices (RAPM), a hallmark of standardized tests since the 1930s. They are visual analogy problems, consisting of two patterns with three shapes and a third pattern with two shapes. The task is to select the missing shape to complete the third triad from a set of alternatives in order match the overall pattern. Participants completed as many RAPM problems in ten minutes as possible, immediately prior to and following cognitive training so the researchers could calculate a possible gain in fluid intelligence.

For the cognitive training portion of the study participants took part in three training sessions on separate days. Participants in the experimental condition completed the n-back task. Here’s how it works. On a monitor a participant sees a series of letters flash in the same location every two and a half seconds. Their task is to indicate if the letter is repeated. The first level is easy because participants must press the space bar every time they see a letter repeated on two consecutive trials (e.g., K followed by K). The second level gets harder – participants must press the space bar every time they see a letter that matches a letter presented two trials earlier. This gets even harder at level three, where they have to make matching decisions compared to three trials earlier. Meanwhile, participants in the control condition completed a 4-choice reaction time task that controlled for task engagement.

Following the RAPM and cognitive training each participant laid in an fMRI scanner and completed the Alternate Uses Task where they generated novel uses for common objects. For example, imagine a researcher asks you to generate a list of uses for a brick. You could use a brick to build a house but a more creative solution might be to use a brick to prop open a door. The purpose of the Alternate Uses Task is to test divergent thinking, an important component of creativity. In Vartanian’s study the participants had 12 seconds to generate uses of a common object, and three seconds to enter their responses using an MRI-compatible keypad. They repeated this task for 20 trials.

Vartanian and his fellow researchers found that the results mostly confirmed the original hypotheses. First, the experimental group improved their RAPM scores compared to the control group, confirming previous research that cognitive training can boost fluid intelligence. However, they did not discover a difference between the two groups with respect to the number of uses generated in the Alternate Uses Task. In other words, participants who completed the n-back tasks did not score higher on divergent thinking, suggesting that training working memory does not boost divergent thinking.

The most provocative findings were at the neurological level. Namely, activation in the ventrolateral and dorsolateral prefrontal cortex, areas of the brain associated with divergent thinking, was much lower during the generation phase of the Alternative Uses Task in the experimental group. This means that even though working memory training and subsequent gains in fluid intelligence did not transfer to better performance on the Alternate Uses Task, participants who engaged in the cognitive training were neurally more efficient during divergent thinking. In other words, just like a long-distance runner uses his lungs and muscle’s more efficiently, participants who practiced the n-back task used less neural resources in the divergent thinking task compared to participants in a control condition.

Gains in fluid intelligence moreover predicted lower activation in the right ventrolateral prefrontal cortex. However, Vartanian reminded me in a recent email that results are correlational. “Drawing a causal link between working memory training and neural efficiency requires more experimentation.”

It’s still unclear if gains from working memory training “transfer” to other tasks. Researchers know that training working memory improves working memory capacity. The question is if working memory training improves cognitive performance across the board just like working out improves your fitness in general. Vartanian says reliable evidence for this transfer effect is the “holy grail everyone is after” even though, he clarified, not every lab has found that the n-back task leads to an increase in fluid intelligence.

All of this brings up the question: What is intelligence anyway? I stated at the outset that intelligence has a genetic component but environment plays a vital role as well. It’s more complicated than that, of course. Consider the Flynn effect. It demonstrates that I.Q. scores have been rising in many parts of the world since 1930. Are people getting smarter or are they just getting better at taking I.Q. tests? The idea that I.Q. is the measurement for intelligence is waning. Yes, I.Q. correlates with success later on in life but it’s unclear what, exactly, it measures. Compounding these queries is the question of multiple intelligences. Researchers like Harvard’s Howard Gardner believe that intelligence isn’t a single thing like a black box in the mind but a series of distinct mental capacities. This makes sense to me – I can write articles on cognitive science but a calculus problem makes me shiver – but the evidence for this line of reasoning is spotty.

Another contentious area of study concerns the relationship between divergent thinking and creativity. Psychologists have historically equated divergent thinking with creativity because divergent thinking is about generating multiple solutions to a single problem, free-flow thinking, and originality. This is true, but like intelligence this paradigm doesn’t address what creativity is in the first place. Today more and more researchers believe that performance on divergent thinking tasks is merely one piece of the creativity pie. This is why a number of creativity researchers are advocating for a broader definition of creativity as well as a shift away from the idea that creative “types” exist, a false suggestion that people are either creative or not.

One of those researchers is Scott Barry Kaufman, NYU Adjunct Professor of Psychology and author of the up and coming Ungifted: Intelligence Redefined. “Pathbreaking creativity requires many years of acquiring a deep knowledge base from which you can draw to make novel connections,” Kaufman explained to me. “Since divergent thinking tests rely so heavily on working memory and fluid reasoning, they don’t allow people to bring their rich database of life experiences to the task. Psychologists are missing out on a large chunk of their creative potential because creativity can be manifested in many ways. By solely judging a person’s intelligence or creativity based on a single decontextualized testing session, you are ignoring that person’s unique mind, and the possibility for that mind to display incredible cognitive feats when allowed to express itself in its own way over an extended period of time.”

Intelligence and creativity are thorny components of our psychologies. Studying them is difficult, defining them even harder. But the overall trend in cognitive science is positive. Researchers like Vartanian and Kaufman are broadening our conception of intelligence and creativity with innovative research and fresh ideas. This is vital. The future of education will depend not just on policy but what we know about how the brain learns, makes insights and solves problems. “Ideally, in educational and other applied settings we would have the ability to train individuals on a few core abilities and then observe performance benefits in many target activities” said Vartanian. “For this to happen, we first need a good understanding of the core abilities that contribute to the desired outcomes, and then we need to differentiate between what can and cannot be trained.”

Image: Renato Ganoza

Samuel McNerney About the Author: Sam McNerney graduated from the greatest school on Earth, Hamilton College, where he earned a bachelors in Philosophy. After reading too much Descartes and Nietzsche, he realized that his true passion is reading and writing about cognitive science. Now, he is working as a science journalist writing about philosophy, psychology, and neuroscience. He has a column at and a blog at called "Moments of Genius". He spends his free time listening to Lady Gaga, dreaming about writing bestsellers, and tweeting @SamMcNerney. Follow on Twitter @SamMcNerney.

The views expressed are those of the author and are not necessarily those of Scientific American.

Comments 14 Comments

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  1. 1. jduringer 1:57 pm 02/5/2013

    How nice to see an article showing human capacity for adaptation …. or possibly “intelligence”. As thorough as an IQ test may be, the unidimensional perspective of intelligence is simply not well adapted.

    The way the word “smart” is most often used is actually quite stupid.

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  2. 2. ildenizen 2:38 pm 02/5/2013

    I think there is a error/double negative.
    “For decades researchers believed that fluid intelligence was >>not immutable<< during adulthood because it was largely determined by genetics."
    "not immutable" implies that is can be changed… which does not make sense in the context presented.

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  3. 3. The Ethical Skeptic 2:41 pm 02/5/2013

    Thank Goodness for IQ tests, or my 6th grade teacher would have taken my grades in math incorrectly and left me bereft in ‘mindless method’ math classes, which bored me no end. Fortunately then taking the accelerated track from that point on (Thank you Ms. Gartner). But the day of encompassing intelligence inside a framework of even single style-set of prejudiced questions, must come to an end. At times I find making sure that I am not swindled by vendors in the Third World streets at my current location, tougher than negotiating the trade deals that drive a change from a social to a capital driven economy. Intelligence involves spotting your own prejudices and not seeing the way you were trained, as infallible.

    We need a test for boredom first. Creativity is directly proportional to desire. A 14 year old who has no money in a third world street can be one smart cookie. Then the input of creativity, once set on a level playing field of interest, will yield an impressive intelligence comparability.

    Not that grades and intelligence relate antecedence, but I hire bored C students over compliant A/B students many times. The latter will not do anything unless they are told how to do it. I do not have time to teach everything my company does to compliant A/B students. Method does not beget intelligence. Much of real business life does not offer one a method. And the moment you use one, someone will beat you because of your adherence to a method. Given me students who have had to be resourceful and creative to get along, who have overcome a disadvantage and have worked hard at what interests them – eschewing wasting time on useless busy work and method, and that is what I need. Make the A/B students into brilliant administrative officials, who execute financial and lab transactions and look good in a corner office.

    But when the tough work needs to be done, dirty, first in the field, creative, intelligent, insightful, tenacious and undaunted – conducted by someone I can trust, then give me a bored C student any time.

    – TES

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  4. 4. smcnerne 2:53 pm 02/5/2013


    You’re right. Thanks for pointing that out. Will correct.


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  5. 5. jtdwyer 3:59 pm 02/5/2013

    Very interesting and well written article regarding very interesting research.

    Taking an opposing tact, having experienced unnoticed degradation of previous capabilities resulting from extended regimens of anemia producing chemotherapy, then suddenly reversed many months later by coincidental prescription of omega-3 fatty acids to treat high triglycerides, I can very much appreciate the degrading effects that environmental conditions can impart on intellectual capabilities.

    In my case, I speculate that the anemia and related effects brought on by chemotherapy damaged the fatty myelin sheaths (produced as an outgrowth of glial cells) that electrically insulate the signals transmitted between neurons by axons. I further speculate that the omega-3 fatty acids supplements provided precursors necessary to restore the myelin sheaths and markedly improve intellectual capabilities that had been diminished for several years.

    The improvement, in June, 2008 following only 1 week of treatment, was very noticeable. In fact I had no idea why my thinking had suddenly emerged from the fog, and spent some time researching conditions that might have produced the beneficial effects. The omega-3 prescription was markedly coincidental and it has been previously implicated in similar cases.

    That my intellectual degradation was most likely produced by severe anemia, and that condition can also be more simply produced by malnutrition, it suggests that a short term therapy of omega-3 supplements, at least for adults who had once been healthy, might be clinically demonstrated to improve IQ test results in subjects that have recently suffered malnutrition, perhaps from some regional catastrophic event or condition.

    Moreover, I speculate that the developing brains of children born into conditions producing malnutrition likely can never attain the intellectual potential they could otherwise have produced.

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  6. 6. Matthewt69 9:35 pm 02/5/2013

    So you can write articles on cognitive psychology but shiver at the prospect of a calculus problem? That’s because writing about cognitive psychology is pretty easy.

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  7. 7. AJM79 10:17 pm 02/5/2013

    Even easier than writing about cognitive psychology is being rude to an author who clearly cares about the topic and writes well in my opinion. Go find somebody to give you a hug.

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  8. 8. PawnPromoter 11:05 am 02/7/2013

    We’re amazed by what people can do naturally in various developmental stages in their lives. Visualization becomes a powerful tool to minds where wonder and breakthrough energies abound. A laboratory for learning awaits us here.

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  9. 9. tezench 6:50 pm 02/7/2013

    Though I.Q. tests should not be considered the sole measurement of intelligence, it did save me from being thrown into the special education classes. When I was in first grade I stopped responding to people. Teachers would ask me a question but I wouldn’t respond. They didn’t know what was wrong with me (this was back in 1975)so they were preparing to send me to special ed. A teaching assistant suggested that maybe I needed to get my hearing tested, because my I.Q. was testing too high for being in special ed. Turns out the tubes in my ears burst and I was only getting by by reading peoples lips, but only if I could see them. I got surgery just in time before it was permanent. It was that I.Q. test saved me not only in school, but also saved my hearing.

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  10. 10. Jerzy v. 3.0. 5:36 pm 02/8/2013

    If intelligence is “50 to 80% genetic” then of course it is possible to improve it. Where this 20 to 50% would come from?

    Curious thing is that, despite fetish of IQ, there are known and accepted ways to improve one’s IQ but are hardly used. You might imagine that IQ training would be as popular as gyms, but not…

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  11. 11. Truthseeker 9:14 pm 02/8/2013

    “Professor Eric Turkheimer demonstrated that growing up in an impoverished and chaotic household suppresses I.Q. – without nurture, innate advantages vanish. ”

    Fascinating. “impoverished and chaotic” are two good words to describe my growing-up years. We were dirt poor and moved around a lot. I went to no less than 4 elementary schools, and 2 Jr. High schools. Plus my mother smoked heavily and drank copious amounts of coffee while she was carrying me. Yet somehow I turned out in the top 25% of MENSA (even though I didn’t find out I was anything more than “bright normal” until I was 25) with a verbal IQ (on the WAIS) and mechanical aptitude off the scale. Are these guys saying that if I’d grown up the scion of a well-to-do family I’d have been REALLY intelligent?

    Additionally I am quite creative. I have been singing my own songs and making my own music literally for as long as I can remember. The oldest poem from my childhood that has survived all the moves dates from my 9th year. I have also written prose both fiction and technical articles. How can any of this be possible if the above quote is true?

    I believe that much of the problem is that the researchers are seldom MENSA level and so are ill equipped to study something so far out of their own ken. They are simply not equipped to truly understand intelligence in the 99th percentile and above. My experience with “normals” as I call them (and, yes, I am
    quite aware of the converse of the term and have no problem with it being applied to me) is that they cannot accept the existence of either abilities or limitations not common to their kind.

    To begin with, I do not believe that intelligence much higher than the first standard deviation out of the mean is truly survival-positive. If it were then the norm would be higher.

    Second, there are no unalloyed blessings or curses in this world. High intellectual ability is pretty much always accompanied by subtle cognitive deficits. I, for example am essentially incapable of rote memorization. I understood multiplication before my 3rd grade teacher finished explaining it but was unable to recite the times tables reliably before the 6th grade. Every other person of such level that I have encountered has similar quirks. Unfortunately normals measure everyone/everything by themselves. If they can do it then everyone must be able to. If they cannot do something then no one can. All my growing up years my peers believed I was either sandbagging or cheating.

    For example, I am a natural speed reader (apparently it is part of a very high verbal IQ) and have been reading adult level fiction since the 6th grade with a vocabulary to match. My 7th grade Reading & Spelling teacher could not – REFUSED TO – believe any 12-year-old could possibly be reading at the speed and comprehension tha t the tests indicated I was. Even when she provided the material to read; she timed my reading and she graded the review quiz to check comprehension she refused to accept the results. To my last day in her class she KNEW I had been cheating even if she had no idea how I did it. That is an extreme example of how normals operate in my experience.

    @Jerzy v. 3.0., do those “known and accepted ways to improve one’s IQ” that “are hardly used” actually improve intelligence or do they merely improve scores in standard tests?

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  12. 12. sjfone 2:05 pm 02/10/2013

    yeah, join MENSA and play sophomoric games all day.

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  13. 13. bucketofsquid 2:13 pm 02/11/2013

    @Truthseeker – Most of the really intelligent people I know see no benefit to M.E.N.S.A. membership. My favorite reason given was “They are a bunch of brain snobs”.

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  14. 14. Jerzy v. 3.0. 4:16 am 02/12/2013


    You are right – only a fool would care about M.E.N.S.A.

    Mensa, however, a name of high IQ society, is not an acronym, but comes from a Latin word meaning table.

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