this post was submitted on 17 May 2025
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[–] 000@lemmy.dbzer0.com 1 points 20 hours ago* (last edited 20 hours ago)

Is this a typical quality of upvoted articles on science@lemmy.world?

[–] troed@fedia.io 228 points 5 days ago (2 children)

the researchers note that the sister raised in the US had suffered three previous concussions

+

the twin raised in Korea described growing up in a loving and harmonious family home, the adopted sister reported a harsher upbringing, colored by regular conflict and the divorce of her adoptive parents

It does seem as if there would be explanations for the unusual difference.

https://www.iflscience.com/identical-twins-raised-in-the-us-and-korea-display-surprising-iq-variations-71357

[–] halcyoncmdr@lemmy.world 147 points 5 days ago (9 children)

That's kind of an understatement. Three traumatic brain injuries is not exactly something that can be ignored when discussing differences in mental faculties.

[–] scarabic@lemmy.world 22 points 5 days ago

It can be ignored if your only priority is dunking on America. I feel sorry for this young person being made into the poster child for everyone who would like to take America down a peg. Even the concussions will somehow get attributed to “the way things are there.”

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[–] WhiteRabbit@lemmy.today 24 points 5 days ago (3 children)

Right, this assertion is invalidated and agenda-driven.

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[–] omxxi@feddit.org 22 points 4 days ago* (last edited 4 days ago) (2 children)

What about the education systems? One of those two countries is heavily denying basic science at schools, teaching creationism as something at the same level as evolutionism, letting religion pollute education, banning books from schools, teaching obsolete two genders theory, etc. Is the study short about the differences in education?

[–] UnderpantsWeevil@lemmy.world 7 points 4 days ago* (last edited 4 days ago)

What about the education systems?

Education, sure. But also environment, nutrition, and stress/trauma.

The US is polluted with heavy metals, our food is awful, and we regularly put residents (particularly young people) in extremely traumatic situations. All of that stunts intellectual development.

[–] kevin2107@lemmy.world 3 points 4 days ago (1 children)

Its a side effect about the differences in education. IQ is relative to the population and education, they slightly increase it to keep the average around 100. The average person 100 years ago had 30 less IQ points, because education and child nutrition were non existent. Cut those things and your average person reverts back.

Other countries have only gotten better, the US has just gotten worse.

[–] GoodLuckToFriends@lemmy.today 3 points 4 days ago (1 children)

they slightly increase it to keep the average around 100

They don't "slightly increase it to keep the average around 100." The average is defined as 100. https://en.wikipedia.org/wiki/Standard_score https://en.wikipedia.org/wiki/IQ_classification

[–] kevin2107@lemmy.world 2 points 4 days ago (1 children)

My explanation is for laymen, 100 in 2025 is not the same 100 in 1925, my point.

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[–] ZombiFrancis@sh.itjust.works 63 points 5 days ago* (last edited 5 days ago) (16 children)

I have children. The amount of trauma a two year old would experience losing their family, being transported to a foreign country and adopted by different people would be ~~traumatic~~intense as hell.

A two year old is not a newborn. That's their entire world blowing up.

[–] silasmariner@programming.dev 14 points 5 days ago

Yeah you can basically completely disregard any other aspect in this study, right? 'massive trauma in early life has strong impact' is the real finding here, and that's hardly a new one

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[–] GlassHalfHopeful@lemmy.ca 15 points 4 days ago* (last edited 4 days ago) (2 children)

This website's use of stock images and gifs were aggravating. The actual case study was worth the read, but only covers a single pair of individuals: https://www.sciencedirect.com/science/article/pii/S0191886922001477

It's certainly interesting. I'm particularly curious about the effects of the multiple confusions:

US had three concussions as an adult, caused by car accidents and from falling on ice. The most recent and severe incident occurred in January 2018, resulting in classic symptoms of light sensitivity and concentration difficulty. US feels she is a “different person,” with increased anger and anxiety. She requires additional time to process information in some problem-solving situations, although she has always seen herself as a poor test taker.

Some of the conclusions seemed a stretch for a single sample. I'm much more curious about more extensive studies with many more subjects.

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[–] taiyang@lemmy.world 47 points 5 days ago (2 children)

16 points, so about a standard deviation. That's big, but your own varience can be just as high; the original point of IQ is a measure of how well you'll do in school to detect who may need additional attention (and not an inherent intelligence) so later aged tests include more on knowledge base while earlier tests are more about things like pattern recognition, mental rotation, etc. Infact, it has to get recurved regularly as each generation tends to be roughly 10 or 15 points higher (although idk about gen Z).

All this is to say that a slump of 16 points doesn't have to be shit like lead poisoning or gas fumes (although that certainly doesn't help, and pollution matters), it can simply be the US education system isn't good at teaching students. Cross culture studies already show that, as do differences between the rich and the poor. Or hell, just playing Tetris raises IQ, lol.

It'd obviously help if this wasn't a click bait article, though. People wanting to know why need to read a lot of actual research to know the myriad of different things that impact IQ and not just "haha US stupid."

[–] victorz@lemmy.world 31 points 5 days ago (1 children)

although idk about gen Z

💀

[–] taiyang@lemmy.world 19 points 5 days ago (1 children)

I technically meant that in regards to not seeing the research lately, but... lol

[–] victorz@lemmy.world 8 points 5 days ago* (last edited 5 days ago) (1 children)

I thought it was hilarious, can't lie. But I don't think gen Z (or alpha, or beta, or whatever gen is the currently self-aware one) are unintelligent, I just think they have shit influence. Parents need to stay extra vigilant in this age.

[–] taiyang@lemmy.world 7 points 5 days ago (1 children)

Real talk the main driver of advances are usually healthier environments, better nutrition and access to knowledge (e g. Via tech). I don't think Z or alphas are getting better in those regards, kind of inheriting the opposite.

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[–] ZephyrXero@lemmy.world 10 points 5 days ago

The article says 7 points is standard in twins. So this is over twice what is normally seen

[–] noctivius@lemm.ee 50 points 5 days ago (21 children)
[–] Steve@communick.news 42 points 5 days ago

Yes. Contrary to current pop-sci thought, it's not actually useless bunk. Epically when differences reach into 2 digits.

[–] null_dot@lemmy.dbzer0.com 29 points 5 days ago (7 children)

I didn't realise it wasn't a thing anymore.

I know it's never been a good indicator of success or even cognitive abilities but it's still a thing that people try to measure.

[–] JasSmith@sh.itjust.works 11 points 5 days ago* (last edited 5 days ago) (2 children)

I know it's never been a good indicator of success

I suppose you might define “success” in an unusual way, but IQ is the single highest correlate with income of all factors. Higher than parental income, race, or residential location.

If you’re interesting in learning more I recommend this article. They cite a lot of data and research. I’m happy to walk you through the directionality topic as well if you’re interested.

[–] scarabic@lemmy.world 9 points 5 days ago

I may need you to walk me past my inhibitions about accepting scientific information from a website called PumpkinPerson that center justifies its articles.

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[–] SunshineJogger@feddit.org 16 points 4 days ago* (last edited 4 days ago)

If anyone else is wondering why their faces on the image are not identical: its a representative stock pic

[–] phoenixz@lemmy.ca 10 points 4 days ago* (last edited 4 days ago)

The article is trash, especially with the added stock photos. Use the source link instead

[–] nulluser@lemmy.world 40 points 5 days ago* (last edited 5 days ago)

The sister raised in the US had an IQ 16 points lower than her sibling in Korea. Previous studies revealed that identical twins typically have no more than a 7-point IQ difference, making this case astounding.

[–] JasSmith@sh.itjust.works 33 points 5 days ago (1 children)

while the other faced hardships with her adoptive family and parents

Does anyone have more info? Abuse, neglect, and malnutrition are proven to reduce IQ. So are the concussions referenced in the article. I would be dubious to make any statements on the back of a single case like this. This is not even outside the realm of possibility of twin IQ variance - albeit unlikely.

[–] Dasus@lemmy.world 24 points 5 days ago* (last edited 5 days ago) (2 children)

So is lead.

Using historical data on U.S. childhood blood-lead levels, leaded-gas use, and population statistics, they determined the likely lifelong burden of lead exposure carried by every American alive in 2015.

https://today.duke.edu/2024/12/20th-century-lead-exposure-damaged-american-mental-health

She looks pretty young, but still.

Also, just schooling, lol. US education sucks donkey dick

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[–] thatradomguy@lemmy.world 27 points 5 days ago

The headline alone just outright insults the other twin. lmao wtf

[–] nasi_goreng@lemmy.zip 18 points 5 days ago* (last edited 5 days ago) (1 children)

There's link for the study: https://www.sciencedirect.com/science/article/pii/S0191886922001477

Personality traits, mental abilities and other individual differences: Monozygotic female twins raised apart in South Korea and the United States by Nancy L. Segal and Yoon-Mi Hur

[–] datalowe@lemmy.world 13 points 4 days ago* (last edited 4 days ago)

It is literally a case study with a single pair of subjects. At first I thought the OP pop sci article was just focusing in on one pair of participants of many. Most of the discussions in threads here seem wholly unwarranted. There are loads of random factors that affect people's development, many of which can't realistically be measured in a study. Maybe one of them happened to become friends with with a classmate that's really into literature and so they started reading a lot! Maybe they are both sensitive to sounds, but only one of them happens to live near an airport, disrupting their sleep at night.

It is not surprising that one particular set of monozygotic twins happens to markedly differ with respect to some traits. There are always outliers in large twin studies too, and researchers don't usually get that hung up about them because everyone knows there are countless factors involved. To be able to have any certainty about the effects of a particular factor you need scale that lets you separate them from the random noise. It's just basic statistics, like what is even anyone doing here. The study itself does make sense, but should be interpreted as extremely exploratory in nature, not something to draw any conclusions from. IMO the researchers themselves are irresponsible in this regard, as they speculate much more than what's warranted in the discussion and conclusions sections. Like, one of their conclusions is "They [the twins] also show that cultural climates can modify values.". First, that is something already widely known and accepted, but second and more importantly, that is not the kind of statement you should make based on a single pair of subjects.

[–] Formfiller@lemmy.world 6 points 4 days ago

Breaking News….America makes you dumb

[–] x4740N@lemm.ee 6 points 4 days ago

With america being the shitshow that it is I am not surprised

I do hope she could move back and get the support of the family in South Korea because she shouldn't have to live in that sithole anymore

[–] tfed@infosec.exchange 11 points 5 days ago (2 children)

@fne8w2ah environment shapes our behavior.

[–] jonne 22 points 5 days ago

Especially if that environment includes head trauma.

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[–] reactionality@lemmy.sdf.org 3 points 4 days ago (2 children)

Lmao at all of the nationalists post-hoccing away at shitty explanations as to why the US isn't just a dumb as a brick nation.

[–] kevin2107@lemmy.world 3 points 4 days ago

Yeah people don't realize IQ is relative to education. If you cut education you get dumber people on average.

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