April 12, 2023 - 4:00pm

New research from the United States confirms a worrying trend — a long-term decline in IQ scores. In cruder terms, Americans are getting dumber every year.

According to a report in Popular Mechanics, researchers from Northwestern University used “survey responses from 394,378 Americans between 2006 to 2018 to examine if cognitive ability scores changed within the US in those 13 years”. What they found was a general, though not uniform, drop-off in measured ability.

Signs of decline have been picked up in other studies too. For instance, research by psychologist Jean Twenge found that Americans at each education level were less verbally skilled in the 2010s than their 1970s counterparts. And before Europeans get too snooty about the apparent dumbing down of America, there’s evidence of similar trends in France, Finland and German-speaking countries.

What makes this transatlantic trend all the more remarkable is that it follows a long period in which average IQ scores increased across the Western world, a phenomenon known as the Flynn Effect. The evidence is now pointing towards a reverse Flynn Effect, in which the intelligence gains of the 20th century are being wiped out in the 21st. 

There’s a lot of scepticism about the real-world relevance of IQ tests, but even if all they do is measure our ability to solve a certain class of abstract problem, we still need to ask why that ability is now in decline.

One theory is diminished motivation, that people today aren’t necessarily less able to pass IQ tests but just put in less effort. However, the fall in IQ scores isn’t consistent. The Northwestern research finds that in one important domain — the solving of shape rotation puzzles — scores are on the rise. If test takers are just getting lazier or more distracted, then surely we’d see a consistent decline.

One of the authors of the study suggests that the emphasis on STEM subjects in schools might be to blame for devaluing the purely abstract. I’m not convinced — a lot of science and most of maths seems pretty abstract to me.

Perhaps we should look for connections to another 21st century megatrend — namely, the decline in mental health among young people. Could these phenomena have a common cause?

An obvious candidate is the influence of smartphones and social media. After all, these are technologies that have altered the medium in which we immerse our minds daily. The influence of tech doesn’t have to be all bad — for instance, computer games might explain the improvement in shape rotation skills — but if cognitive ability and mental wellbeing have declined over the same period that we’ve become addicted to our glowing rectangles then, at the very least, we should acknowledge a correlation.

We should also take a hard look at over-attentive parenting styles and the ongoing safe space mentality in the education system. I doubt that robbing children of the chance to work things out for themselves is contributing much to their mental resilience or to their cognitive development.

One thing is certain. Over the course of 21st century, the way in which we form young minds has changed under the influence of profound technological and cultural shifts. The results are now in, and there is much cause for concern.


Peter Franklin is Associate Editor of UnHerd. He was previously a policy advisor and speechwriter on environmental and social issues.

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