IQ Isn't Set In Stone, Suggests Study That Finds Big Jumps, Dips In Teens

http://www.npr.org/blogs/health/2011/10/19/141511314/iq-isnt-set-in-stone-suggests-study-that-finds-big-jumps-dips-in-teens?ft=1&f=1001&sc=tw&utm_source=twitterfeed&utm_medium=twitter

by llambda • 15 years ago

42 63 15 years ago

npr.org

ern2• 15 years ago

Link to original study: http://www.nature.com/nature/journal/vaop/ncurrent/full/natu...

llambda• 15 years ago

Nature is paywalled so only the abstract is viewable for me.

asolove• 15 years ago

"Nature is paywalled" is a sentence I fear I will see again, with a different meaning, at some time in the future.

afterburner• 15 years ago

Great phrase.

rhizome2• 15 years ago

Well of course IQ isn't set in stone, IQ is based on the results of a test that babies can't take. QED.

technomancy• 15 years ago

Honest question: do people actually believe something like that could be hard-coded? It just seems like a horribly depressing worldview to believe that you're stuck with whatever INT points you rolled at the start... not even to mention being trivially disprovable.

gabyar• 15 years ago

Just like all things, both nature and nurture are strong factors. Certainly genetics play a factor in IQ, just as they do with other personality traits such as extroversion, or physical traits, such as height. Set in stone would be a huge exaggeration of genetic causation, but people will have certain propensities from birth.

codexon• 15 years ago

I believe it could be hard-coded just like the reason why I am not even 6 feet tall coding away my health while people like Shaq and Yao Ming make millions a year for being 7 feet tall.

Depressing? Yes. That's just the way life is.

What is even more depressing is that some people think you can will yourself to be smarter, and if you don't, you are just lazy.

rhizome2• 15 years ago

"People" do, yes. I'm not sure which ones or how to characterize them, but I'm sure there are smart people who think so just as much as dumb ones. To a certain degree though, I do think intelligence can be acquired just like skateboarding skills or anything else that can be learned.

pjscott2• 15 years ago

I think there's some semantic confusion here.

1. There are degrees of mutability; "changeable" versus "hard-coded" is a false dichotomy. For instance, I can increase my arithmetic ability with practice, but I'm never going to be able to improve it so much that I can diagonalize huge matrices faster than a computer.

2. Whether or not a belief is depressing has no bearing on whether or not it is true.

So I would reframe the question a bit: to what extent can IQ be changed? How reliable are the tests? And if we can improve IQ, what's the best way to do it? For example, childhood malnutrition can lower IQ, so improving childhood nutrition can pay off big. The Flynn effect -- the rise in IQ scores over time -- suggests that there are other things that can raise people's IQ as well, so if we can find and exploit those, and they actually raise intelligence, then that would be great.

hugh32• 15 years ago

Tragically, whether or not something is depressing appears to be uncorrelated with whether or not it's true.

Anyway, clearly "IQ" isn't hard-coded. People get different scores on different days on different tests, and people tend to get higher scores over time as they get better at solving the dozen or so standard classes of problem that you tend to get (just ask me what this cube looks like unfolded!)

On the other hand, there is a very real phenomenon called "intelligence", and people have it to varying degrees (so do animals, to even more widely varying degrees), its effects are well known to everybody from our experience in the real world, and IQ tests are vaguely correlated with it. And it does seem to be largely genetic.

tomjen3• 15 years ago

Why is it that people are so fixated on IQ? We already know that things like whether the child can wait 20 minutes on a marshmallow at age 4 is a better indicator of scholastic success than IQ.

I fear people use IQ as an excuse for a (lack of) their success rather than face up to it and improve (or just accept and move on).

pjscott2• 15 years ago

Setting aside the possibility that the delayed-marshmallow-gratification thing has been exaggerated by people wanting to downplay IQ, and taking it at face value: the fact that IQ is not the single most important predictor of scholastic and/or life success does not make it unimportant. It warrants discussion, especially if it can be improved.

For example, eliminating childhood malnutrition can improve IQ significantly across whole populations. Isn't that something to be excited about?

cema• 15 years ago

  eliminating childhood malnutrition 
  can improve IQ significantly

I suspect it can improve the marshmallow-related behavior as well. But I could just be excited about the elimination of malnutrition.

hcayce• 15 years ago

"Why is it that people are so fixated on IQ?"

I suspect that people who ask about IQs say more about themselves than an IQ number says about any particular individual.

tassl• 15 years ago

Humans love to classify and compare. Most of us compete to demonstrate we are better and the intelligence is not different. Having a way to measure this human parameter precisely is a normal consequence.

Plus, from a more useful perspective, we need to have some way of measure a parameter if we want to study it. If we were trying to compare the results of two different strategies to improve the intelligence, we would need a precise method to measure the intelligence of every individual.

scott_s3• 15 years ago

Because it is something we can measure, and science can only deal with things we can measure.

rhino42• 15 years ago

Not quite. Popular culture "can only deal with" things that can be put on a simple number line, because they collectively like to be able to say definitively "this person is smarter than that other person", when the reality is (of course) far more complicated than that.

As far as I know, the scientific community agrees that IQ is not a strong predictor of true "intelligence"...

rflrob• 15 years ago

Any idea how reliable a single IQ score is? If you repeat the test a week or a month later, too soon for changes to reflect a significant change in cognitive abilities, but far enough away to get rid of effects like a poor night's sleep, stress from school or relationships, &c., by how much is the score expected to vary?

vacri6• 15 years ago

A proper IQ test done under the same conditions (well rested, etc) will give the same results. It's vulnerable to poor conditions - if you're not well rested, you're not going to do as well as you could otherwise.

hugh32• 15 years ago

In my childhood I did enough IQ tests [1] to be able to say "Oh, it's one of this class of problems again". I assume that people taking repeated IQ tests get better at them, because there's a limited selection of problem types.

[1] Only three or four. I'm sure there are lots of kids out there getting far more over-tested than I.

ellyagg• 15 years ago

Suggesting that IQ is not set in stone also implies that IQ exists. That they don't claim otherwise, and in fact show structural brain changes in accordance with the measured changes, should be well noted by folks who make a habit of discounting it. It should also be noted that IQ was already thought to be malleable into the teens, so I'm not sure why the researchers were so surprised.

tomlin3• 15 years ago

It's not that people deny it exists, or discount it all together - it's just a terrible indicator or measurement of one's capabilities. Measurements should be accountable. A few cups of coffee or a bad sleep shouldn't matter if IQ is as reliable as some like to believe.

Since it is used to judge one's abilities, it's hardly fair to use it as a practical measurement, just as BMI is impractical to use for judging a body builder's fat percentage.

Anecdotally, medication which I take for ADHD/PI doesn't permanently alter my brain's chemistry, yet my IQ takes a noticeable dive without it.

alphamale30002• 15 years ago

Nonsense.

Of course bad sleep will affect your IQ, and it doesn't make it less reliable. Why? You brain is less reliable when you had bad sleep, and IQ is a measurement of its peak performance. If you're not at peak performance any given day, your results will show.

Tichy• 15 years ago

Of course it exists: it is a test that gives a result. Personally I don't find the "structural brain changes" bit not very enlightening. Is it surprising that a brain that performs differently has changed? It would be more surprising if it hadn't changed.

What about those taxi drivers who had enhanced brain regions for geographic knowledge? Kind of the same thing...

Homunculiheaded5• 15 years ago

I love when people ask "what does your IQ score measure". The only thing it can possibly measure is your ability to perform an IQ test. Now you can ask the question "What does your IQ score strongly correlate with", but I'm pretty sure as it stands 'intelligence' is not well defined enough assign it a quantitative value (or even know if one can be defined).

I used to hate standardized tests (and still somewhat do in principle) but when you can show that a test score correlates to performance it does make sense to assist in making decision when there are very large sets of data to process (like college applications). It turns out that SATs do correlate somewhat to freshman year performance. It doesn't really matter if it's for the right reason, if you have thousands of similar applicants it makes sense to use that data point if there are no other options. This is the logic of machine learning too: I don't really care why 2 variables correlate, if they do it can help me make decisions.

The issue for me is that I have yet to see anything interesting about what IQ really correlates to. Pretending it is a test that measures intelligence is completely asinine if you take 2 minutes to think about what that claim means.

jpulgarin• 15 years ago

Correlates somewhat to academic performance, lifetime earning, SAT scores etc...

bad_user• 15 years ago

I think it is generally understood by psychologists, sociologists and statisticians that intelligence is not something that you can "measure". Nobody in the know even pretends that.

What happens is that people would rather put faith in the correlation between IQ scores and intelligence, rather than nothing at all. It's annoying as hell as IMHO a +/- 15 points doesn't mean anything, but that doesn't stop people making decisions based on that. On the other hand you can clearly say that somebody with an IQ of 240 is gifted or that somebody with an IQ of 60 is challenged.

The problem with SAT scores is that people doing well on it are the people fresh out of high-school. You cannot give a SAT test to somebody that's been 10 years out of high-school or to a 10 year old.

vacri6• 15 years ago

A real IQ test is a decent measure of general intelligence. It does, however, take a trained professional several hours to administer - precisely because this is necessary to counter most of the criticisms levelled at "IQ tests are crap". Components of the IQ test can also be used to track individual aptitudes. But because it's so resource intensive to conduct, pretty much any time you've heard someone say "My IQ is -foo-", you can be fairly sure it's not from the formal test.

Everything else that calls itself an IQ test is really a form of pop science quiz and of course has flaws. Any test that you're supposed to administer yourself is not the IQ test - that's the easiest first step.

Homunculiheaded5• 15 years ago

but how do you quantify intelligence in order to determine that there is a relationship between it and an IQ test score? If you can say that a real IQ test is a decent measure of intelligence, how to do you know this?

Let's say I have a Teakettle test which assigns a score to the temperature of the water in a teakettle based on only qualitative properties of a teakettle (is it whistling, is it rumbling, does touching it cause pain?). This test is probably good at assessing the extreme cases (water is 212 F, water is around 70F) but I'd guess it's a poor predictor of temperature. Now if you gave me a thermometer I could see how correct my test was.

The problem is we don't have a thermometer for intelligence (that I know of) and more important I don't know if there is any consensus that 'intelligence' can even be assigned a quantitative value the same way the vibration of molecules can.

Now maybe the IQ test, like the Teakettle test, is a good summation of qualitative properties. Now you can compare this quantitative value to others to show a useful correlation. The Teakettle test may be a really great way to predict time to tea-time. An IQ score can only be useful if it shows a strong correlation to other, quantitative things (SAT score, salary, life expectancy, number of hairs in eyebrows)

To say that a real IQ test is a decent measure of intelligence seems to be at best a tautology.

gwern2• 15 years ago

> It does, however, take a trained professional several hours to administer - precisely because this is necessary to counter most of the criticisms levelled at "IQ tests are crap".

Don't the shortened IQ tests correlate pretty strongly with the longer ones? When I read psychology papers, even ones dealing with children, they pretty frequently use speeded or abbreviated ones without apparent qualms.

byrneseyeview3• 15 years ago

I'll take the other side of that bet!

What kind of odds would you give me that a group of people in the 10th percentile will have a higher average income than a group of people from the 90th percentile? If all IQ measures is your ability to take an IQ test, I think you'd be pretty confident that the bottom 10% will perform about as well as the top 10%. So, would you up up for 1:1 odds on that?

If you're willing to bet consistently with your beliefs, please get in touch; my email address is in my profile.

Steko6• 15 years ago

"If all IQ measures is your ability to take an IQ test, I think you'd be pretty confident that the bottom 10% will perform about as well as the top 10%."

Unless the top 10% has some systemic advantage at taking IQ tests. Type words into a search engine for further inquiries in this area.

Homunculiheaded5• 15 years ago

I think you're confusing measures X and correlates with X. Snowfall probably correlates very strongly with the number or people skiing on a weekend, but it does not measure the number of people skiing on a weekend.

Let's say you win this bet (which I wouldn't take since I never argued that was the case in the first place), all you have shown is that the ability to answer questions on an IQ test has a strong correlation with income. How does this have anything to do with intelligence, which the test claims to measure? If you where to say that "well this means that intelligence is strongly correlated with income" this is tautological since the IQ test is your only way to measure intelligence in the first place.

My assumption that IQ scores probably don't correlate that strongly to many things is based on the observation that we don't use it that much. If you look more thoroughly there are, as expected, obviously correlations between IQ and many things, but how strong those correlations are and the variance make many of them interesting but not fantastically useful.

Correlating with the extremes is not that interesting, now if you where to show that the is a strong correlation between IQ test percentile and income percentile across the board that would be interesting. If you're really interested there has been research into the correlation between IQ and Income and it's about 0.4-0.5 [1]

1. http://en.wikipedia.org/wiki/Intelligence_quotient#Income

esrauch2• 15 years ago

> I love when people ask "what does your IQ score measure". The only thing it can possibly measure is your ability to perform an IQ test.

This is a completely random statement. You could just as easily say that an analog scale doesn't measure weight, it measures how much a spring compresses when an object is placed on top of it. Since the spring is different every time, even the same scale is not going to be the same every day.

Measuring something and what it correlates with is exactly the same thing, and the distinction you are making is absurd pedantry.

I don't really have any strong opinion about your actual stances.

Homunculiheaded5• 15 years ago

Weight isn't some property we just defined based on the compression of a spring, and we aren't measuring just a correlation. When we measure weight on an analog scale we already know several, quantitative physical properties of the spring, we also have a mathematical model of how exactly the compression of a spring is directly related (not correlated) to the force of weight. Given that we know all of the additional variables of a spring we take it's compression and determine the weight. Inaccuracies in analog scales are not due to some stochastic process involved with the correlation between weight and compression, but inaccuracies measuring the quantitative properties of the spring.

In an IQ test we are merely counting a set of qualitative properties (answered question n correctly). There is no underlying model that we are using to determine "intelligence", there is nothing quantitative about the IQ test other than counting the correct answers. We don't even have a quantitative model of intelligence at all, so there is simply no way to measure it. It is not pedantry to say that what an IQ test does is merely measure answered questions and not intelligence. If there where a.) a quantitative model of intelligence, and b.) a formula mapping this to IQ tests then, yes we could say we were measuring intelligence in the same way an analog scale measures weight.

Tycho• 15 years ago

How many other people here have avoided taking an IQ test there entire life thus far?

winestock• 15 years ago

The following two paragraphs are from the article:

"Price and her colleagues used brain scans to confirm that these big fluctuations in performance were not random — or just a fluke. They evaluated the structure of the teens' brain in the early teen years and again in the late teenage years.

"We were able to see that the degree to which their IQ had changed was proportional to the degree to which different parts of their brain had changed," explains Price. For instance, an increase in verbal IQ score correlated with a structural change in the left motor cortex of the brain that is activated when we speak."

So, if there were structural changes in the brain that correlated with change in IQ score, then IQ likely tells us something other than "this person does this well or badly at IQ tests." Many people are very skeptical about IQ tests. As depressing as it is, the basic science behind psychometrics has been mostly stable for decades. Look up the work of Linda Gottfredson (sp?).

As for this particular study, psychometricians already knew that generalized intelligence (the so-called g-factor) crystallized in adolescence or early adulthood. The surprising thing about this study is how much change some of the subjects showed. Going from the fiftieth percentile to the ninety-something or, worse, going in reverse, is a big deal. The researchers behind this study should get more funding to continue their work.

gwern2• 15 years ago

Very interesting; for me, the cool thing is not the variations (after all, we have long known from childhood IQ tests that there's a lot of variation along the way to one's adult IQ) but the nailing it down to the structural brain changes as opposed to more transient or environmental stuff like, say, having a bad day or test-retest effects or something.

IQ Isn't Set In Stone, Suggests Study That Finds Big Jumps, Dips In Teens

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