Can IQ be increased?

Factual Questions
1

My search results yielded no answers, so I’m going to ask here:

Can someone increase their IQ with effort? I was told years ago by someone far smarter than myself that you are pretty much born with your IQ. He basically laid it out as your IQ is your ability to learn, not necessarily how smart you are right now. Is that true?

I feel like I’m 200% smarter now than I was 20 years ago, even if I thought I knew it all back then. I have a good ability to research and learn things, and a good ability to ascertain facts and data. I’ve also gained an increasing sense of warranted skepticism as well as a well-calibrated B.S. detector. Are these improvements indicative of my baseline IQ, which is the same now as it was 20 years ago–just an indication that I have ability to learn? Or am I actively improving my IQ?

Subsequent question: Can one just “learn how to be good” at taking IQ tests? Learn the main forms of questions and figure out how to answer them well. Would that artificially increase one’s score?

Just for a point of reference, this is where my question comes from: Last evening I was thinking about some attributes of a family member, attributes I consider indication of a really high IQ. He’s not as up on research or facts and figures, so in a debate type situation I’ve got him cornered on facts alone, but I still suspect he probably has a much higher general IQ than myself.

So it appears I have no idea how IQs work, so please, Dopers, straighten me out.

2

Since the score you get on IQ tests IS your IQ, it can’t be artificially increased, only increased. Your IQ is not your ability to learn, it’s your score on an IQ test. No single test can test your ability to learn. And, no, you’re not born with a set IQ.

3

There’s the score on IQ tests, and then there’s the real property that those tests are attempting to measure. Score on IQ tests can certainly be improved with practice. The real underlying property probably can be, too, but that’s more difficult to assess.

4

AIUI, intelligence is mostly innate, but can be enhanced through things like nutrition, a stimulating life with lots of info, talking to people who are more intelligent, better sleep, better health, etc.

TLDR; mostly nature, but some nurture too. But I’m sure there are limits. You just can’t jump from 100 to 150. Ten points, maybe, but not fifty.

5

That would also be my take. The score on an IQ test can be improved with practice; typical IQ test questions of the “Which is the next image in the sequence?” sort are, like many other skills, something that you can get the knack of if you do many of them and get an understanding of what it is that is wanted of the testee. The underlying abstract concept of intelligence is probably something much more static and difficult to improve, but since our preferred way of assessing this concept is via IQ tests, we don’t have a way of finding out.

6
7

Of what practical relevance is this question? What I mean by that is:

I think what you’re trying to get at is like, if you consider a human trait like height, we certainly know of many ways a person can stunt their height through inadequate nutrition etc. but it’s not like people can just try hard to get taller. Some people naturally end up taller or shorter through innate factors like genetics.

In contrast, if you look a human trait like weight, this is something which human decisions can influence to a large degree. There’s obviously an innate factor and just because it’s possible to change your weight doesn’t mean it’s practical or easy but it is in theory under a person’s control.

So what I think you’re trying to get at with this question is “Is intelligence more like height or more like weight” and the simple answer is “it’s a little bit of both”. We’ve arbitrarily decided to call the part of intelligence that’s more like height the “IQ portion” of intelligence whereas we call the stuff that’s trainable “skills” or “training” or whatever.

Rather than fixate on the labels, I think the more useful part is to focus on which bits of intelligence feel more like height and which bits feel more like weight (or strength might be a better analogy because that’s trainable).

8

IQ tests were not developed to measure the high end, and have never done this very well. They were designed to find children in school who need extra help.

They also were not designed to measure the intelligence of adults.

IQ is a ratio of chronological age to the “age” of academic achievement. As such, adults don’t really have an IQ. When you hear adults tell you they have an IQ of whatever, it’s usually the last tested IQ they had in school, which was probably from before they were in high school.

The highest upward measure of most IQ tests used in schools is 150. Anyone who scores above this is simply labeled “above testing parameters.” That’s why it’s such a joke when TV geniuses say they have an IQ of something like “187.” Especially if they are adults.

Yes, some people have an extrapolated IQ, and if you pay a psychologist a lot of money, you can get an IQ test at any age, and yes, Mensa has some kind of test they give potential members, but those are all extrapolated IQs.

Yes, you can increase your IQ.

You can always increase your ability to perform on an IQ test, and that is how an IQ is measured. IQ tests problem-solving skills, memory, general knowledge, and reading ability (as a discrete skill), in order to predict performance in a school environment. You can always improve your ability to achieve in school, no matter how old you are, so yes, you can increase your IQ.

Is there some quality called “intelligence” separate from achievement? Maybe. Can we measure it? We try. There is a lot of research and effort put into trying to measure it in people on the lower end of the scale, to determine what sorts of interventions are needed. There is a lot at stake in developing a good prognosis for someone who is developmentally disabled.

But for someone on the high achieving end, IQ is mostly a curiosity. Once a person is “above average,” and not needing any special help at all, there’s no need to measure IQ. Actual performance is more important in determining things like placement in accelerated programs.

Just as a side note, a lot of people who were middling achievers in school before the 21st century, and later diagnosed with AD[H]D or anxiety disorders (sometimes as part of autism, sometimes not), and either given medication, or behavior therapy, or both, have attempted college again after failing once, and found it a breeze. No doubt they would have scored much higher on IQ tests if they’d had intervention the first time around.

So yes, there are ways to increase IQ. Lots of them.

ETA: full disclosure: my last tested IQ was in the 7th grade, and it was 142. That’s phenomenal. I never lived up to it. However, in college, as part of a psych experiment I volunteered for, I took a multiple choice test, the purpose of which was to measure one’s ability to take multiple choice tests. I scored a 98%. The next highest score was 76%. So I do not think IQ tests measure anything but one’s ability to take an IQ test.

9

Assuming the underlying question is really ‘can I get smarter/more intelligent?’, and that we don’t have to go down the rabbit hole of definitions of intelligence etc, but rather, discuss this at the high level, I’d say the answer is ‘yes, but it gets harder’.

Clearly you’re smarter now than you were as a baby, so it is unarguable that intelligence/‘smartness’ can develop; the only question is where the limits lie - is it something that stops completely at a specific point; is there a hard limit, and if so, what are the causes of those things?

It seems likely to me that development of individual intelligence is going to follow generally a sigmoid curve - starting off slow-ish, increasing in rate (as it goes through a sort of critical mass event - gaining intelligence helps you seek more ways to gain more of it), then easing off, probably as a result of both the end of adolescent physical development, and the attainment of a ‘good enough to be useful’ level of smarts.

10

RivkahChaya says that “IQ is a ratio of chronological age to the “age” of academic achievement. As such, adults don’t really have an IQ. When you hear adults tell you they have an IQ of whatever, it’s usually the last tested IQ they had in school, which was probably from before they were in high school,” and that “the highest upward measure of most IQ tests used in schools is 150.” The first of these statements is out of date and I think the second is not quite accurate. I.Q. tests were indeed created to measure just the intelligence of children. They were originally really quotients, not places on a normal curve. However, this is no longer true.

When I.Q. tests were created in the early twentieth century, they were a test (or a set of tests) which would allow the tester to say that a particular child of age X was as smart as the average child of age Y. Then the I.Q. of that child would be Y/X (times 100). So if a child of age 8 scored as well as the average child of age 12, their I.Q. would be 12/8 * 100 = 150. Or if you wanted to be more accurate a child of age 101 months scored as well as the average child of age 143 months, their I.Q. would be (143/101) * 100 = 141. That only worked for children then.

But that’s not the usual meaning anymore. Now a person is placed somewhere on a normal curve (for whatever group you include that person in) with a mean of 100 and a standard deviation of 15. So a person who gets a score that three standard deviations above the mean for their group on an I.Q. test has an I.Q. of 100 + (3 * 15) = 145. So now it’s possible to speak about an I.Q. of an adult.

Also, typically, typically I.Q. tests will measure up to an I.Q. of 160, not 150. If somehow (and this is obviously impossible) we could give an I.Q. test to every human who ever lived, the highest score on the test would still only be 200. This is because if you put 108 billion points on a normal curve, you would have the highest one at about six and two-thirds standard deviations above the mean. Then the I.Q. score would be at approximately 100 + (6.66666… * 15) = 200. Someone claiming to have an I.Q. above 160 is lying or using some worthless bad test. Someone claiming to have an I.Q. above 200 is claiming something that’s not even theoretically possible.

There’s something called the Flynn effect. It was discovered that the average person today who scores 100 on today’s I.Q. tests would have scored 103 on tests from ten years ago or 106 on tests from twenty years ago, etc. (Actually, it’s more complicated than that, but it’s all I’m going to say in this post.) So either human beings have evolved incredibly fast since the beginning of the twentieth century so that the average intelligence is much higher or else I.Q. tests are not just measuring something that a person is born with.

It’s unlikely that evolution works that fast, so presumably the tests are also measuring something else besides the intelligence that that people are born with. Lots of thing have changed over the past century. Besides things like better health today, it appears that the environment that children grow up in allows them to develop their skills better that make them score higher on I.Q. tests. This is very complicated, so please read the Wikipedia entry on the Flynn effect and maybe then go on to reading a book on the subject. Alas, this has forced me into doing what I really need to do in many posts, which is saying that this subject is too complicated for just a single post. Really, you need to read a book to understand this.

11

This seems right. Before I did a invigilated IQ test I did two or three full practice exams (I actually enjoyed doing them) and definitely found it increasingly easier to solve the problems. By the time of my test I breezed through it. Which I assume is not how it is supposed to happen. I was 12 (or 13) and scored a ridiculously high IQ result; higher than the maximum I could achieve as an adult now. So if the only measurement of IQ is via that test then, no, in my case IQ cannot be increased! Which is obviously ridiculous.

As an aside - after being told I was in the top fraction of 1% of kids, I got extremely average grades
at school so that tells you all you need to know about IQ tests.

12

If, after scoring very high on an I.Q. test, you got just average grades, it doesn’t necessarily mean that you really aren’t smart and the score was a matter of luck. That’s only one possibility. It could mean that you goof off. It could mean that teachers and other students treat you badly (for whatever reason) and you got discouraged and don’t work. It could mean that you got moved to the toughest classes, so even though you are doing well, your grades aren’t very good. It could mean that you have one of a number of possible psychological problems.

13

As Wendell almost just said:

My take:
As many have said, “IQ” is whatever thing it is that these tests measure. “Intelligence” is a far more multifaceted and amorphous thing that could never be meaningfully reduced to a single number.

The height vs weight or height vs strength analogy made up-thread is a decent one. Some argue intelligence is more like physical agility or flexibility. Some folks inherently have more than others, and although that amount is measurable in isolation, its real value is as an enabler or a multiplier of other aspects of physical prowess = “athleticism”.

IOW, a more agile person can become a better baseball player than a less agile person. But agility in and of itself doesn’t confer baseball ability. It confers the ability to gain baseball skills and perfect them to a higher level more readily. Assuming you choose to to apply yourself to those ends.

14

You got me.

I’ve always had a curious mind so I had a lot of interests - most of which weren’t schoolwork.

15

I don’t have much meaningful to say, but I love this thread and I really appreciate the replies. The Flynn Effect is really fascinating. The general progressiveness of intelligence is modern society is interesting, too.

We live in an age where you literally have the answer to *nearly any question in your pocket at all times, yet so many people wallow in their ignorance. Strange to think we’re actually smarter as a whole than before…

16

BAck in the early 70’s when I was in jr high, the IQ test I took showed my score to be 135. I had no clue if that was normal or below average at the time. Everyone said I was was really smart as a kid, and as I got older.

I’m considered pretty intelligent in my high tech job, and I always get high scores on exams. The kids I grew up with who seemed dumb or average, seemed to stay that way as adults. None of them went to college. Pretty much all the smart people I grew up with finished school and have had successful careers. Not sure what any of their IQ scores were though.

Either you have the ability to learn, or you don’t. Not sure if that has anything to do with IQ though.

17

Oh, the brain is an organ, like the heart, or the liver, and some people’s work better than others’, but there’s probably also a point at which it’s working optimally, and how you exercise it becomes most important.

18

Exactly. Doing well at whatever counts as intelligence, such as problem solving (only one example) can certainly atrophy with lack of use, and can probably be improved over whatever is average for that person with training and practice.

19

At the very least, you can take practice tests to understand exactly what is being asked on the test - this will save you a decent amount of deducing the question. Look at the example image further up the thread. If you were an adult who’d never seen one of these in 10 or 20 years, would you have an idea what the answer was? How many such problems could you do during a timed interval? Actual questions are much more complex, but the concept is the same - what’s the patterns? This was the situation my wife ran into - we went online to research aptitude tests for a job interview. An hour or two of going over such puzzles made them much easier to solve. This is of course the same concept as people who study for the SAT (instead of paying someone to take it for them…)

I think of IQ as your ability to solve problems. I attribute the Flynn effect to the variety of novel experiences modern humans are exposed to. That idiot tube has some value, as does the internet now; it has vastly widened the experiences of (some) modern humans… I have never been to an actual horse track race, for example, but in the past 60 years how many have I seen - in movies and TV? How many F1 car races? Roman chariot races? The pyramids, surfing, parachuting? How many views of the Eiffel tower or the Matterhorn? How can some rube from rural Kansas in the 1920’s compete with that, if they only saw maybe one black and white movie a week, usually shot on a back lot with constructed scenery? How can the local guy with a fiddle compete with the experience of nonstop music from a streaming service?

I come across as clever, too, because I have seen and retained numerous puzzles. (Like the classic - “OTTFFSS…” what letter comes next? Once someone tells you it’s “One Two Three…” then “E” for “Eight” is obvious. How many of these do you run across when information is pouring out of a pipe at you by the megabit? How many practical jokes or scams or betrayals has the modern human heard of or seen in movies, compared to that guy from Kansas?

My impression is that IQ is about half inherited genetically and maybe half constructed by the evironment - mind-exercising experiences early in life, plus things like nutrition and social interaction… But that’s just a a guess.

Ultimately, how do you tell? I suppose that a study could be done of adopted children biological parents’ intelligence, but then how do you compensate for environment?

20

Agree with all the @md-2000 has said. But there’s an interesting effect described between the lines of that first paragraph. Which bears back on the OP’s initial questions.

As he says in later paragraphs, the Flynn effect is (probably) the result of more environmental enrichment on average vs e.g. 1920. And better nutrition on average. We know on average we’re taller than 1920s Americans too.

Because IQ test results are scaled versus the other test takers, your individual IQ score is a function of

  1. Your personal innate {whatever IQ tests measure} versus the current average test takers.
  2. Your personal degree of Flynn-ish enrichment versus the current average test takers.
  3. Your personal degree of test-taking practice versus the current average test takers.

Number 3 is what I want to talk about. There’s an arms race here.

If everybody is taking their IQ tests cold, never having seen any practice material, then the test is just measuring my items 1 & 2. But once some people are practicing, your score will go down unless you practice as much as the average person does.

If most kids in your school are getting lots of coaching & pre-tests at home but you do none of that, you’re not any stupider. But you will get a lower score.

What that means as a practical matter is whatever score you did get on some test you really took, you need to evaluate how much test prep you did versus everybody else. And if you want an actual measure of your innate {whatever it is}, you’ll need to adjust the score appropriately to offset that difference in your practice vs average practice. But how to know how much is “average practice”? Aye, there’s the rub.

OTOH, to the degree the test score actually predicts something about your future relative performance versus those other test takers, e.g. college grades, college entrance exams, performance in a problem-solving job, etc., any adjustment is wrong-headed. In the rat race the rats who trained better do win more often.

Bottom lines:

  • Now that most folks are practicing for most formalized testing, anyone who doesn’t do that is tying their shoelaces together before they begin the race.
  • The impact of practical levels of #3 (and #2) are probably worth 5-10 points each. IOW a decent chunk of one standard deviation. If you’re (or the test giver) is actually trying to measure #1, all of that #2 & #3 effect is noise obscuring the underlying signal. And it’s a loud noise.