Higher education has never been a worse investment. There's so little time or incentive to read, and it's hard to sit down and say "I'm going to read a book". It's hard to read a book and also watch tv and also talk to friends etc etc, but that's how we spend all day - constantly interacting with media or socially.

I've had increasing trouble reading books for years. It stresses me out, I can't just sit for hours reading, I have things to do. It takes real... something - focus, mindfullness - to actually sit down and think in an explorative way that isn't strictly driven by work.

This isn't that surprising. IQ tests a specific type of intelligence, and we probably don't leverage that sort of intelligence day to day. Instead, we create hyperfocused individuals and build structure and process around them so that they can collaborate. Being generally intelligent and having general problem solving skills is less and less important, or at least we treat it that way.

Who would struggle to be smart in a society that rewards idiocy and blind alignment to asinine political discourses, a society where the loudest opinion is the only one that matters. Enjoy the permanent state of frustration that being "smart" or "rational" will bring you.

Most politicians are exasperatingly dumb, most celebrities are witless mannequins and the richest man in the world is a simple minded moron that acts like a 16yo in the middle of a sugar rush. Don't blame the youth for not wanting to be "smart" when they can see that plenty of mediocre adult content creators can earn more in a week than your average office worker in a month and when their role models are dudes vlogging about getting rich gambling on JPG monkeys and shilling for crypto rug pulls.

The data from the study has a giant elephant in the room: war. The participants are 18 year old Norwegians who were forced to take a military examination. The reason they do an IQ test is to evaluate if they are suited for a more analytic role, such as radar and comms. The peak result is for the birth year 1975, i.e. tests taken in 1993. During the cold war, a soviet attack was a real possibility, but that threat pretty much evaporated in the 90's. I did this exam in 1998 and the general vibe was pretty much: "why are we still doing this?" Few people took it seriously.
At the time of writing, much of this thread is centered around (a) dismissing the study based on considerations that were ruled out within the article, and (b) dismissing the format and value of IQ tests. Let's set these aside and discuss the open question:

> What specific environmental factors cause changes in intelligence remains relatively unexplored.

What might these factors possibly be? Some candidates I am aware of, that are known to affect IQ: heavy metals in infant formula [1], increases in baseline CO2 levels [2], stress [3], deficiencies caused by soil depletion [4]. Leaded gasoline seems to have been ruled out by timing.

It's interesting to me that this started in 1975 and is observed across Europe. Do we know of any major changes in habits or industrial practices that started around that year?

[1] https://www.legalexaminer.com/home-family/baby-food-lawsuits...

[2] https://medium.com/wedonthavetime/co2-affects-our-thinking-9...

[3] https://www.nytimes.com/1983/05/31/science/study-ties-iq-sco...

[4] https://www.scientificamerican.com/article/soil-depletion-an...

An environmental cause appears likely, since this trend is being observed in many countries. Both the increase in IQ to 1975 and the drop thereafter could have environmental causes.

The increase could be due to improved nutrition following WW 2, such as better access to food overall and the iodization of salt.

For the decline, my money is on PFAS (https://www.sixclasses.org/videos/PFAS) and organohalogens more generally. Iodine is also a halogen, and all the other halogenated compounds we are pumping in the environment could interfere with iodine metabolism. These compounds are in nearly everything, and we're using ever larger quantities of them.

There is evidence this affects fetal development and cognitive functioning years later (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2799472/), which is also why jurisdictions are banning flame retardants (https://www.tuvsud.com/en/e-ssentials-newsletter/consumer-pr... https://www.sixclasses.org/videos/flame-retardants )

The analytical side of me doesn't understand how scores on a test that baselines the average to X (in the case of IQ, it is baseline of 100), then distributes them around that baseline on a normal distribution curve can go down over time.

The article didn't link data so I can't dig in further.


The article insists several times this is not due to genetics, because people with lower IQ don't have more children. This is not true[0]. What the article may want to say is that it's not due exclusively to genetics.

Given fertility is negatively correlated with intelligence, and how hereditary IQ is, it's just a matter of time until IQ declines.

This is not so shocking, how many kids does your typical college professor have before 35, is it 0 or 1?

[0] https://en.m.wikipedia.org/wiki/Fertility_and_intelligence

In france, kids in the 50s could write with a nib/ink by 6, before starting primary school. We are lowering our education requirements since the 70s. Basically since the rise of "international governing education", see failure modern maths and global reading.

And while IQ is not too much related to education, we let kids do what ever, when ever for a so call peace of mind, so yeah a kid who is never challenged can't have broad skills. I would dare to say that video games are saving IQ scores but for all the wrong reasons (fast pattern recognition and spacial movement related tests).

> Norwegian researchers analyzed the IQ scores of Norwegian men born between 1962 and 1991 and found that scores increased by almost 3 percentage points each decade for those born between 1962 to 1975

Statements like this have always made me question these tests. Ten points in IQ represents a movement of one standard deviation in intelligence. To believe the quote above would mean that there was a massive increase in intelligence between the 1960's and the 1990's. But an increase of one standard deviation across any trait at a population level is very very unusual, and likely would have been noticed long before any studies were conducted.

Put another way, do we really believe that someone with slightly below average intelligence in 1962, say an IQ of 85, is the intellectual equivalent of someone with a significantly below average IQ (e.g. 75) in 1990? An IQ of 75 typically means you're not in public school or if you are, you're in Special Ed.

There are three strong factors that come to mind:

(1) Physical fitness. These same years have seen the explosive growth of obesity and related lifestyle diseases. A greater percentage of people in first world countries (and increasingly elsewhere) are either obese or overweight. I recall reading that one way to keep your mind sharp is to be physically fit (cf: "Spark: The Revolutionary New Science of Exercise and the Brain" by Ratey and Hagerman). The corollary could be that if you are not physically fit, your IQ will suffer.

(2) Pollution. Air pollution has been shown to affect IQ scores (https://www.unep.org/news-and-stories/story/air-pollution-li...). It could be that greater pollution has been causing lower IQ scores.

(3) Sleep. I recall reading that people get lesser high quality sleep than they used to. It has very clearly become easier to stay up late today. Poor sleep is really bad for you for a number of reasons, including your cognitive performance and brain health.

I blame smartphones. Really I do. My overall ability to focus and consume longform content has gone up dramatically since ditching my phone several months ago.
>"The study looked at the IQ scores of brothers who were born in different years. Researchers found that, instead of being similar as suggested by a genetic explanation, IQ scores often differed significantly between the siblings."

I can think of a multitude of reasons younger siblings should, on average, have a lower IQ than their older brothers. Could this independently account for the 'decline' that researchers are measuring?

I wonder whether we need to take another look at our modern school education system. Maybe some of the things we (rashly?) ditched had some importance that we didn’t realise at the time. Like learning poetry by heart, learning multiplication tables, “old-school” teaching methods that have now fallen out of favour.
Is this attributable to leaded gasoline? https://en.wikipedia.org/wiki/Thomas_Midgley_Jr. "Use of leaded gasoline, which he invented, released large quantities of lead into the atmosphere all over the world. High atmospheric lead levels have been linked with serious long-term health problems from childhood, including neurological impairment"
The article doesn't mention pollution which is a HUGE contributing factor to lower IQ.

Leaded gas wiped nearly 10 IQ points off of everyone and is still used in general aviation.

It is illuminating that the paper doesn’t mention lead while discussing IQ decline in the recent decades. https://m.youtube.com/watch?v=IV3dnLzthDA
Anyone with some domain knowledge willing to pitch in whether it's correct people are equating IQ with education in this thread?
With a global average IQ hovering around 80, it really terrifies me what the future has in store given how manipulable the masses are via social media. The recent Phillipines presidential election is a perfect example. There's a sort of cutoff I've noticed around 85-90 IQ where at or below that, people can simply be spoon-fed whatever form of reality you wish for them to accept. The truth no longer matters when someone's entire reality is shaped by 30 second TikTok videos that are actually just performances masquerading as "POV real life". All of those absurd fake videos we see and laugh at only exist because they work.
I wonder if there is a negative impact produced by people having kids later in life - the reduced sperm and egg quality must play some role in this.
"In a separate study that has not been released, he and his colleagues looked at existing research in an effort to demonstrate that staying in school longer directly equates to higher IQ scores."

...or maybe, it just improves your test-taking ability?

The actual research comes from 2018: https://www.pnas.org/doi/10.1073/pnas.1718793115

The one thing that stands out is that the sample population comes from Norwegian Military conscripts. Since the end of the Cold War militaries have contracted across NATO and Western Europe. I would be curious anyone from Norway could comment on whether there might be a fundamental shift in the data. If a lot of smart kids avoid conscription by going to University somewhere then the results of these tests ought to trend downwards.

This is a really interesting, simple and clever study design and I look forward to reading it. That said, I think there is strong evidence for selection against intelligence at genetic level. The question is more "does it explain the Flynn effect and its reversal", or "is it large enough to have an important effect?" See our paper: https://ideas.repec.org/p/uea/ueaeco/2021-02.html
Idiocracy a documentary?
This is from 2018 to be clear.
> Access to education is currently the most conclusive factor explaining disparities > in intelligence, according to Ritchie.

That sounds weird. Doesn't that mean they're "measuring intelligence" wrongly, as plenty of people without extensive formal education are extremely intelligent?

eg those same people getting further formal education may indeed score higher on these IQ tests, but the education is in no way changing the persons IQ

Intellect need stimuli, education not stereotypical Ford-mode workers formation like neoliberal schools have planted ad any level of the society because is easier to govern Ford-model workers than acculturated Citizens.

That's is. If we teach from the early childhood we nourish intelligence, if not we nurtured stupidity. The rest might matter to a certain extent but it's mostly background noise.

My suspicion is that having direct access to all information has offloaded some of our cognitive capabilities to our devices. Also, making everything political-- and as such being told what to think about every topic doesn't really help us exercise our critical thinking skills. Maybe we need to "use your brain" more- as my dad would have said.
IMO the Idiocracy scenario[0] is a likely candidate for a Great Filter[1].



While causal factors are not identified, the study ([1]) concludes that the decline is due to environmental factors, and neither to genetics nor to other family-related causes.

[1] https://www.pnas.org/doi/10.1073/pnas.1718793115

Are there any credible / non scammy ways to take one of these tests online? I haven't looked much myself but it seemed like they would largely be garbage social media bait, or make you take a long test and ask for money at the end.
I am too dumb to understand what they actually did. (or too lazy understanding the study on my mobile). Can anyonr explain? I mean the IQ tests were not the same for every batch, right? So how do you milk the result out of the data?
This is a garbage CNN article about a laughable iq study that’s so bad it borders on propaganda.

The study focuses on “two brothers” cohorts and makes the claim that iqs within families are on the decline, but fails to adjust for confounding factors, like the selection bias inherent in their cohort selection process.

Other studies show that first borns have a higher iq than later siblings, and to a greater extent than what this study found!

Iq isn’t boosted by higher education. This isn’t up for debate. Outside of malnourishment and sensory deprivation it it mostly heritable.

I suspect that long-term benzos, alcohol and/or marijuana use is contributing to this to a significant degree. Would be interesting to see data on this.
Aren't IQ tests basically BS?

> TruTV’s Adam Ruins Everything is known for debunking accepted wisdom. It took less than two minutes to demolish IQ tests:

Quote: https://www.insidehook.com/article/history/charles-darwin-sp...

Video: https://youtu.be/W3oUqKUx2o0

So two hypotheses: Generation X was a generation of unparalleled genius effortlessly surpassing their idiot ancestors before who merely built the modern world and their children who merely consumed and produced vastly more written content than ever before whilst playing with increasingly complex abstractions on computers, or IQ test comparisons between dissimilar populations don't really mean very much, because the "quotient" is a ranking mechanism for solving a certain type of paper puzzle, not an actual thing.
Isn't IQ designed to average at 100?
Forced redistribution of wealth is dysgenic, and there is no single greater indicator for success in life than IQ.
Maybe we'll finally achieve equity, where everyone has the same (low) IQ. Wouldn't that be the most ideal situation?
IQ tests seem woefully outdated and highly biased at best. As many note, the ability to do well on these tests is greatly increased by practice, as with most testing procedures. The notion that an IQ test is a standalone measure of innate intelligence is not well supported.

Perhaps specific areas could be tested, such as memory - but even with such a basic concept, we know that the ability to memorize a long string of numbers is a highly trainable skill. If we go to 'higher level' mental processes, such as pattern recognition, symbolic interpretation, analytical capabilities (i.e. higher maths), and creative capabilities (inventiveness), again we see that these abilities are highly trainable.

The only real way to sort this out would be to apply the same educational program to a large cohort of individuals, over the course of at least a year, involving intensive one-on-one tutoring, and administer the prospective IQ test both before and after this process takes place. This has come up before and such a study has never been done to my knowledge, nor has anyone ever pointed one out.

Decades is understating it. The beginning of civilization marks the start of the first downtrend in hominid brain to body ratio. There are a few different theories about why, but I find the systemic one the most plausible. The increase in the complexity of a system comes with a reduction in complexity of the parts.
I know mine has
Why is the best source of IQ information we have "Norwegian military conscripts"? Maybe we should make all politicians take an IQ test, so we get a good sampling of the smartest people at any given point in time.
There s no use to fret about it. I think nature is telling us that IQ (or intelligence) is not needed. sorry folks you ve been optimizing the wrong thing

Is there a method to dumb yourself down? asking for my smart friends

The book I'm reading Weapons of Mass Instruction explains this as being part of the goals of forced schooling as designed by Carnegie and other industrialist to make easier to manage laborers.
It is probably how CNN works too, but with declining journalistic creedo.
IQ alone got us Skinner and H-bombs. If EQ has gone up, that's a win.
It's because the highest IQ people of the previous generation were almost all hired to find out ways to capture everyone's attention as much as possible.

Not surprising that they succeeded doing that.

Check the background d of the two authors of the original publication: two economic professors … who have been measuring IQ.

Sounds legit.

I suspect it is partly environmental pollutants.
I always had a problem getting the point of IQ tests. It necessarily makes assumptions on what intelligence is, seems a bit self referencing. It measures how you conform to what a specific group of people think intelligence is...

So I can't really take into high consideration inference based on average IQ test results. It could also mean that people are becoming intelligent in stuff not measured by the test. I really don't know.

Another point to consider: even if we had the perfect way to measure intelligence, so what? Why waste an intelligent person time doing a test about intelligence? What does this accomplish?

Great to finally have some data. The tendency has been pretty clear for some years now, with more and more crazy ideologies spawning among the young.
I believe the effect of Tiktok will be unprecedented
I think Taleb gets it right about IQ, lack of it is a dis-qualifier and beyond a point after certain IQ score it becomes noise.
"A single new study shows something scary and/or surprising" is a near certain sign that the conclusion is wrong.
No, they aren't - and by definition (IQ across the population has a fixed mean and standard deviation).
People are becoming smart in different ways and the tests aren't keeping up.
Regression to the mean.
Interesting...could this explain secular stagnation?
It’s because of changing demographics
co2 levels is also getting higher which have negative impacts on learning and concentration.
Brawndo has electrolytes.
I'd like to say 'hi' to xkcd with his religious attitude towards Flynn effect and readiness to ridicule others over that.
I thought the effect was just localized to this website.
ITT one step away from "IQ is correlated to genetics (and also your race)"
I thought IQ tests were pseudoscientific anyway?

If the number doesnt have any rigorous meaning then who cares if it changes, up or down, could mean anything.