Ignore IQ Tests: Your Level of Intelligence Is Not Fixed for Life

IQ test

This article was originally published on The Conversation.

We’re getting more stupid. That’s one point made in a recent article in the New Scientist, reporting on a gradual decline in IQs in developed countries such as the UK, Australia and the Netherlands. Such research feeds into a long-held fascination with testing human intelligence. Yet such debates are too focused on IQ as a lifelong trait that can’t be changed. Other research is beginning to show the opposite.

The concept of testing intelligence was first successfully devised by French psychologists in the early 1900s to help describe differences in how well and quickly children learn at school. But it is now frequently used to explain that difference – that we all have a fixed and inherent level of intelligence that limits how fast we can learn.

Defined loosely, intelligence refers to our ability to learn quickly and adapt to new situations. IQ tests measure our vocabulary, our ability to problem-solve, reason logically and so on.

But what many people fail to understand is that if IQ tests measured only our skills at these particular tasks, no one would be interested in our score. The score is interesting only because it is thought to be fixed for life.

Who Is Getting Smarter?

Standardized IQ tests used by clinical psychologists for diagnostic purposes, such as the Weschler scale, are designed in such a way that it is not easy to prepare for them. The contents are kept surprisingly secret and they are changed regularly. The score given for an individual is a relative one, adjusted based on the performance of people of the same age.

But even as we become better educated and more skillful at the types of tasks measured on IQ tests (a phenomenon known as the “Flynn effect”, after James Flynn who first noted it) our IQs stay pretty much the same. This is because the IQ scoring system takes into account the amount of improvement expected over time, and then discounts it. This type of score is called a “standardized score” – it hides your true score and merely represents your standing in relation to your peers who have also been getting smarter at about the same rate.

This apparent stability in IQ scores makes intelligence look relatively constant, whereas in fact we are all becoming more intelligent across and within our lifetimes. The IQ test and the IQ scoring system are constantly adjusted to ensure that the average IQ remains at 100, despite a well-noted increase in intellectual ability worldwide.

Politics of IQ Testing

Psychologists are aware that intelligence scores are somewhat subject to cultural influence and social opportunity, but some have still insisted that we cannot raise our IQ by much. This is because our general intelligence (or “g”) is a fixed trait that is insensitive to education, “brain training,” diet, or other interventions. In other words, they say, we are all biologically limited in our intelligence levels.

The idea that IQ is fixed for life is built into the questionable politics of IQ testing. The most serious consequence of this is the use of IQ tests to blame educational difficulties on students rather than on teaching systems.

But it is the job of psychologists to find better ways to teach, not to find better ways to justify the poor performance of students. This particular use of IQ tests has caused one leader in the field of intelligence research, Robert Sternberg, to refer to IQ testing as “negative psychology” in a 2008 article.

All Is Not Lost

Those who hang dearly onto the notion that IQ is fixed for life have managed to ignore decades of published research in the field of applied behavior analysis. This has reported very large IQ gains in children with autism who have been exposed to early intensive behavioral interventions once they have been diagnosed with learning difficulties.

Another 2009 Norwegian study examined the effects of an increase in the duration of compulsory schooling in Norway in the 1960s which lengthened the time in education for Norwegians by two years. The researchers used records of cognitive ability taken by the military to calculate the IQ of each individual in the study. They found that IQ had increased by 3.7 points for every extra year of education received.

More recent studies by John Jonides and his colleagues at the University of Michigan reported improvements in objective measures of intelligence for those who practiced a brain-training task called the “n-back task” – a kind of computerized memory test.

My own research, in the field of relational frame theory, has shown that understanding relations between words, such as “more than,” “less than” or “opposite” is crucial for our intellectual development. One recent pilot study showed that we can considerably raise standard IQ scores by training children in relational language skills tasks over a period of months. Again, this finding challenges the idea that intelligence is fixed for life.

So it’s about time we reconsidered our ideas about the nature of intelligence as a trait that cannot be changed. Undoubtedly, there may be some limits to the development of our intellectual skills. But in the short term, the socially responsible thing to do is not to feel bound by those limits, but to help every child work towards and even exceed them.


Image by Wichy / ShutterstockThe Conversation

CATEGORIZED UNDER: Mind & Brain, Top Posts
MORE ABOUT: intelligence
  • http://againstjebelallawz.wordpress.com/ Enopoletus Harding

    But what many people fail to understand is that if IQ tests measured only our skills at these particular tasks, no one would be interested in our score.

    -This absolute nonsense without a citation remains absolute nonsense without a citation.
    The question is not whether IQ can be substantially affected by the environment. The question is whether IQ can be substantially positively affected in a lasting fashion after age 17. The “Improving fluid intelligence with training on working memory” paper is certainly interesting, but it is an outlier. Replication is needed.

  • cbusenke

    humans already have far more intelligence than they ever needed and exponentially more brain power than 99% ever put to use. I can’t believe we’re getting smarter, either a statistical skew from the subjects selected or the test is being adjusted like social security payments. AHRA, the average human retardation adjustment. I’m not using the word dropped from common usage because of the bastards that use it to refer to those with mental challenges. I’m using to refer to the masses, folks who make tv shows like kardashians a profitable enterprise, Darwin award winners like the gun safety instructor who just got killed because his 8 year old student couldn’t handle the full auto UZI he gave her, etc…intelligence is a curse. I think we’ll set up AI that works well enough for them to take off and leave us here to fade into fossil status. wow, I’m not feeling so cheery today. apologies all

    • lucan

      Experience counts for a lot of our intelligence….and,it does count even though it isn’t added into the IQ score.

  • duguesclin

    Keep the denial of the G factor. Good luck with that. Nobody -of importance- has ever said that you cannot train to score more in IQ tests. What it’s been said, and demonstrated again and again, is that relative distances between individuals stay the same if they receive the same training. Also, that in the long term, almost all the gains obtained from that training are lost if the individuals don’t keep training. In fact, the older the individuals get, the more they re-approach their base IQ if they stop working on it.

    • ericlipps

      Spearman’s g isn’t holy writ; it’s a hypothesis, and one with some significant problems.

      Even if you were right, though, the unhappy fact is that individuals in our society don’t “receive the same training.” Or the same feeding, or the same medical care. Therefore, observed differences among groups (which is what the biggest flap is about) can’t reliably be ascribed to genetics.

      • Hayden Smith

        That is utterly beside the point.

        • ericlipps

          No, it isn’t. You’re assuming a great deal.

          For one thing, I wasn’t talking about training for the IQ test, the way so may people do for the SATs. I was talking about both formal education and the informal sort everyone gets in the course of living their lives. Someone in the inner city who has grown up poor in a violent neighborhood will not get the same stimulus, the same medical care or the same nutrition that someone born into a stable middle-class environment will.

          And that matters. there probably is some underlying genetics-based level of intelligence, but how genes are actually expressed depends on environmental factors. One could be born with the genetics for genius, but if one grows up in dire poverty eating lead paint chips to dull hunger pangs (reportedly, they taste sweet, which of course makes them tempting to hungry little kids) one isn’t likely to reach one’s full theoretical potential. Ditto if one simply grows up seriously malnourished, or was born to an alcoholic mother, or . . . but why go on?

          It always amazes me that so many people are willing to concede that a bad environment can stunt physical growth but turn on a dime when the issue is IQ–especially when the issue is IQ differences between economic or racial groups.

          • Don’t Even Try It!

            …and that could explain why the IQ of the average “Black” is only 85% that of the average “White” person.

          • ericlipps

            Actually, those statistics are outdated; the gap is less now.
            But there are other factors, as well. When IQ tests first came in, they were applied to, among others, Eastern European Jews–who were found to average out as subnormal. Such findings were used to justify immigration restrictions which were still in effect in the late 1930s, when Jews were desperately trying to escape Europe before Hitler’s thugs caught up with them. Now, of course, anti-Semites warn of the danger posed by Jews’ supposedly superior intelligence.
            The point being that IQ tests don’t actually measure intelligence, but rather competence in a carefully selected set of skills which are believed to contribute to success in school–and in America, the tests rest not only on fluency in standard English but on assumed familiarity with various items of the (white)majority culture.

          • Don’t Even Try It!

            I appreciate the information. Thanks, I guess we are never too old to learn.

          • Reg

            That was the first time in history, and the last, that Jews were accused of being stupid.

            As for American blacks, their neighborhoods may be a tad unkempt, but by world standards they are amazingly rich. Big-city libraries are far better stocked than suburban ones, and there is no charge to use them.

          • ericlipps

            And what difference does that make, if you’re given so miserable an early education that you can’t read at all or at best find reading difficult, and if those of your peers who actually do succeed academically tend to be treated (not always, but too often) as “discipline problems” until they take the hint and resume their assigned place at the bottom of the heap? Even white kids who are too studious and get grades that “spoil the curve” take loads of crap, and it’s far worse for blacks.

      • duguesclin

        Yes, because it is impossible to compensate on those variables. It’s impossible to design the studies to compensate for that, right?

        Except that this has been done systematically, consistently, since the fifties or before.

        The truth is that some people will always deny any and all congenital differences in any and all human parameters just because for them absolute equality and meliorism are moral apriorisms.

        • ericlipps

          Actually, it isn’t possible to “compensate” for (not “on”) those variables, and it has therefore not been done “since the fifties or before.” See my prior comment.

          At this point, it’s probably worth nothing that the seminal study in this regard, by Britain’s Cyril Burt, which concluded that IQ differences both among individuals and between groups was 80 percent inherited, has been exposed as outright fraudulent. Burt claimed to derive his conclusion from a study of twins raised together versus twins raised apart–but not only do his numbers not add up, it turns out that at least some of the twin pairs he claimed to have examined didn’t even exist. His work was swallowed eagerly, it seems, because it confirmed what people wanted to believe–that people occupy the social positions for which nature and God meant them.

          And even if none of this were true, 80 percent heritability isn’t the same as 80 percent genetic, because we “inherit” our parents’ (and usually their parents’) social conditions, and these can make a big difference in how, or even whether, we grow up. “Heritability” in the genetic sense is a lot easier to establish in a pea patch á la Mendel than in human society.

  • ericlipps

    But what many people fail to understand is that if IQ tests measured only our skills at these particular tasks, no one would be interested in our score.

    On the contrary; the first IQ tests were originally designed to identify individuals who were likely either to have trouble keeping up in school or, at the other extreme, were likely to be exceptional students who might benefit from enhanced instruction. It didn’t take long, though, for people to find other, less benign uses for them.

  • karldwed

    “This apparent stability in IQ scores makes intelligence look relatively constant, whereas in fact we are all becoming more intelligent across and within our lifetimes.”

    It isn’t certain that the “Flynn effect” reflects any real changes in general cognitive ability (what most people call intelligence). Hollow IQ gains caused by changes in education and test familiarity are two reasonable hypothesis.

    • cbusenke

      it’s also worth noting the expression “in like Flynn” was created to refer to Errol Flynn and his many successes with women and the fact that he had a large penis

    • facefault

      Why call changes in IQ from education “hollow”? People’s abilities matter more than how they came by those abilities.

  • Raymond Rogers

    “My own research, in the field of relational frame theory, has shown that understanding relations between words, such as “more than,” “less than” or “opposite” is crucial for our intellectual development”

    Is Roche making a subtle dig at his fellow psychologist’s IQ?

    In any case: the comments here and some of the article above treat IQ as though it was a real thing. I have the contrary view that it is just a made up thing (perhaps like Christo’s art) with no objective reality. A collection of questions and scores that that try to evaluate how well a person will do in a particular culture (ours); it is correlated with that but that doesn’t make it an objective thing. I think a culture like Genghis Khan’s or Ancient Sparta would make up different scores because the intellectual parts that go into living would be weighted differently. Trying to sum up the multiple factors in human thinking by one number is a fools errand. In fact I believe some long term study in the 1930’s showed that high IQ only moderately correlated with social or intellectual success. Or another example that I read is that Napoleon only had an IQ of about 128 (Incidentally I don’t know if that is really held to be true ). I would say the weighting in the tests/factors were a poor indicator of “social success” in that case.

    • Hayden Smith

      I am dying to hear how Napoleon’s IQ would have been tested. The test came into existence decades after he died.

      • Hayden Smith

        A real thing? I don’t know. Is your intelligence a real thing?

  • TMS71

    The effects of relational frame theory training notwithstanding our common sense tells us that some people are just innately smarter than others just as some people are innately physically stronger than others. It’s a good thing that intelligence seems amenable to some of our efforts to improve it but this does not really mean that it is not a stable lifelong trait. The author has a point that it is the job of educators to find better ways to teach but those better ways will not level the playing field. They will benefit the smart as much as the less smart. So we should implement them but we should not expect them to erase the performance gap between the innately more intelligent and the innately less intelligent. These differences are most likely the result of many genes that create a more powerful information processing brain in some than in others just as genes create more powerful muscles in some than in others. I believe that the author has made an unwarranted jump from the fact that some interventions seem to improve IQ to the conclusion that innate intelligence is not a major explanatory factor in school and life achievement.

    • facefault

      Common sense also tells us that the Earth is flat and the sun revolves around it. That’s why we supplement common sense with, you know, evidence.

      Also, why would we expect substantial genetic differences in intelligence? There’s no empirical evidence for significant differences – except for the still-unconfirmed KL gene finding, no gene that affects IQ makes even a full point of difference.

      And there’s no theoretical reason to expect differences – genes that affect intelligence should be fixed in the population, since intelligence has been comparably valuable in every environment humans have occupied. (In muscle strength there’s a tradeoff between slow-twitch and fast-twitch muscle, so there’s a tradeoff between strength and endurance depending on environment; but there’s no evidence for such a tradeoff in brains).

      • TMS71

        There are many genes that affect intelligence. They don’t work in a linear fashion where they add a discrete number of IQ points. They affect neural development and account for differences in neural function. They can have synergistic effects. All that needs to be true is that people differ in the number of these favorable gene variants. That would be a genetic basis for difference in intelligence. There needn’t be genes with large effects.
        I said that common sense tells us that some people are innately more intelligent than others. You don’t think that some people are innately more intelligent than others?

        • facefault

          All that you’re saying is plausible, but lacks evidence. This includes the idea that some people are innately more intelligent.

        • ericlipps

          Actually, there are two separate issues here: genetic differences among individuals, which are reasonably well documented, and genetic differences between groups, especially racial groups, which are controversial not merely for the obvious political reasons but because it is impossible to adequately control for environmental factors in studying tis issue. Don’t argue this with me; take it up with the researchers who’ve actually evaluated the studies done in this area.

          Some people, of course, desperately want to believe that certain groups are just plain inferior (üntermenschen, you know) and therefore deserve to be at the bottom of the heap forever.

  • http://democraticprogress.net/ JohnB

    The test is completely bogus. The simple fact that they have to keep readjusting should be a glaring red flag for starters. It is like you were trying to see how fast a car could run a quarter mile but kept changing the definition of what a mile is.

  • eetom

    There is a great difference between intelligence and the ability to score in IQ test. With more education a person can do more with his intelligence and has a higher IQ score, but that does not mean that he is more intelligent.
    That America can extract more oil from its wells does not mean that America has more oil underground. When a driver learns better driving technique does not necessarily mean that he has a better car.
    How confused can some “scholars” be?

    • artfuldgr

      the author confuses capacity with contents..
      a person who has a very high iq, but little learning, has a lot of capacity, and not muc content.
      a person who has an average IQ, but a lot of learning, has filled their capacity….

      the size of the glass does not change (much), but most of us dont fill the glass anyway

  • michael scott

    I never knew that some people actually believe that a person’s intelligence is set for life and cannot be changed. I’ve always known and believed that anyone (who doesn’t have some serious mental deficiency preventing them from being able to do so) can increases their intelligence by learning more knowledge, and then learning how to use that knowledge wisely by using it and not just letting what they’ve learned sit dormant because of their lack of using it. That’s pretty stupid in my opinion that many intelligent people actually choose to believe that a so-called IQ test dictates that you can never become more intelligent and increase your IQ level; especially when many are constantly changing the rules of IQ tests in order to justify this false belief. That reminds me of how many choose to ignore true scientific studies that prove that the so-called theories of evolution, the big bang, and the steady state, are false teachings. I pray that those who believe that no one can increase their intelligence level (IQ) will realize that that’s totally wrong. It’s only logical that as one learns more and uses what they learn that their IQ increases; how else does one explain people becoming very wise by the time they’re old or very old.

  • dnamatters

    The article implies that an individual’s IQ score can vary widely during his or her lifetime. The only direction of change actually observed, however, is downward. The author ignores the substantial research that shows that while intensive educational interventions can raise childhood IQ test scores by several points, these gains are completely or almost completely lost by adulthood. Study after study has found that while such shared environmental factors can have a big impact on childhood IQ, they have little or no impact on adult IQ, which no one seriously claims can vary widely, except in the case of brain damage. The author offers an explanation for this regression to the group mean: black children who are raised by more intelligent white parents will, they claim, see their IQs eventually fall because of the less intelligent black peers with whom they associate in adolescence and adulthood. This supposedly “anti-racist” position, though, is not as convincing or straightforward (remember Occam’s Razor) as the alternative position: that adult IQ is much more heavily influenced by genetics than by education. In other words, by adulthood people generally manage to develop the maximum cognitive potential of which their brains are capable — but no more. Black children blessed with high-IQ white adoptive parents eventually regress to their own group’s mean IQ score of 85 by adulthood. This in spite of their higher than expected early childhood IQ score. To believe that this regression is due to the effect of adolescent peers would go against everything we know about the importance of early childhood to adult outcomes. We would have to believe that adolescence is a more important formative period than early childhood in one’s cognitive development.

  • ericlipps

    Only an idiot would say that “everybody is the same.” That would mean, for example, that you and I are equally intelligent.
    And here we go again: apparently if you can’t have Cyril Burt as an unchallengeable authority to buttress your claims of racial differences in IQ, you’ll take the Beeb. I’m surprised you’re not invoking the curse of Ham as well.
    You’re still wrong, by the way: even if it’s true that “at least” half of the difference between individuals in IQ is due to genes (which isn’t true just because the BBC supposedly agrees that it is), it doesn’t follow that the same is true for groups. I know it sounds counterintuitive, but it happens to be true. Comparisons among individuals within a group, or in a mixed group, don’t necessarily reflect actual differences among groups.

  • Bibibibibib Blubb

    Must be why the richest country in the world is Qatar with 78(apparently mentally retarded) average IQ. Also a very low crime rate with very diverse population mostly from South Asia… run by conservative Muslims.




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