What about the education systems? One of those two countries are 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?
this post was submitted on 17 May 2025
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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.
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.
Yeah people don't realize IQ is relative to education. If you cut education you get dumber people on average.
The article is trash, especially with the added stock photos. Use the source link instead
Breaking News….America makes you dumb
Manga authors "write that down write that down!"
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.
Gotta say as someone who experienced traumatic brain injury I also feel like I'm a different person, and not as bright as I used to be. The doctors estimate I lost somewhere on the order of 15-20% of whatever that was.
Exactly, there's a lot of different factors that can affect cognition.
If anyone else is wondering why their faces on the image are not identical: its a representative stock pic
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
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
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.
Look at what Americans consume. There's your answer.
yeah, totally not the concussions.
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.
That's kind of an understatement. Three traumatic brain injuries is not exactly something that can be ignored when discussing differences in mental faculties.
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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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."
although idk about gen Z
💀
I technically meant that in regards to not seeing the research lately, but... lol
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.
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.
You might be right on that, indeed. At least some countries are backpedaling hard on all of the above right now.
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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.
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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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.
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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The headline alone just outright insults the other twin. lmao wtf
iq still a thing?
Yes. Contrary to current pop-sci thought, it's not actually useless bunk. Epically when differences reach into 2 digits.
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This summer, they're gonna get their parents back together!
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.
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