Last fall, a Norwegian psychology professor named Lars Dehli was asked to give a lecture on intelligence. It had been a while since he had taught the topic, so he looked forward to revisiting it. As he explained in an essay about the experience, he decided to start the lecture by discussing the so-called Flynn Effect—the well-known phenomenon, first observed by James Flynn, whereby measured IQ scores have been steadily increasing since World War II. “It’s always fun to tell students that their generation is the smartest people who have ever lived,” Dehli wrote.
But as he gathered data to build an up-to-date chart, he was “very surprised” by what he discovered: “IQ has actually started to fall.”
Dehli was not the first person to notice this decline. In recent years, a growing number of researchers have been documenting what has become known as the Reverse Flynn Effect. Consider, for example, a recent paper published in the journal Intelligence that studied IQ scores over time in an American population. It found a steady decline in almost every intelligence metric studied as part of a 35-item assessment.
Here’s a chart that shows these declines broken out by education level:
There’s no consensus on the causes of the Reverse Flynn Effect. But in a recent podcast appearance, James Mariott, a critic and columnist for The Times of London, summarized a hypothesis that has been gaining traction: as we switch our information consumption from print to digital devices, our ability to think deeply degrades.
As Marriott explains:
“Print requires us to make a logical case for a subject. A really significant feature of books is that if you make a case in print, you have to make it logically add up. You can’t just assert things in the way you can on TikTok or on YouTube…print privileges a whole way of thinking and a whole way of processing the world that is logical, that is more rational, that is more dense information, that is more intellectually challenging. If you lose these things in our culture, which I think we really are in the process of losing them, it’s not surprising that people are getting stupider…and that we seem to find that IQ is declining.”
The data on the Reverse Flynn Effect includes several pieces of evidence that support Marriott’s claims. The IQ reversal, for example, seems to begin right around 2010—the point at which smartphones began their rapid ascent to ubiquity. In addition, according to the Northwestern study, the demographic suffering the steepest declines is 18 to 22-year-olds, who also happen to be the heaviest users of smartphones.
As with most psychological findings, it is unlikely that we will ever fully attribute this effect to a single, specific cause. But based on common sense and lived experience, there’s certainly a ring of truth to this device hypothesis.
It’s grown standard to say things like, “my phone is making me so dumb!”, but this is often intended to be a figure of speech; a self-deprecating shorthand for the reality that the things we do on our phone are dumb, or that we spend less time doing “smart” activities than we used to. If these technological interpretations of the Reverse Flynn Effect hold up, it might turn out that this quip is way more literal than we may have originally assumed.
It’s definitely tempting to assign this research to an easy culprit like smartphones, but this feels like pretty clickbaity writing for this setting. There’s no defensible evidence provided in the writing and measures of intelligence like IQ tests are already questionable in their own right. Isn’t it also possible that our past measures of intelligence may be growing out of date as memorization and recall become less important to expertise? I’m not saying I disagree with the premise that turning away from reading print is a net loss and linked to smartphone use, but I think you need to provide a stronger argument than a possible tenuous correlation before making that suggestion
Exactly. We’ll said.
Just wait till AI gets fully integrated!!
This post came at the perfect time, since I was responding to a classmate about how critical thinking might be impacted as AI becomes thoroughly embedded in every facet of our lives. Thank you for the work that you do. Navigating a career in tech is a constant uphill battle against dying brain cells, and your writing continues to provide a hopeful counterpoint.
The most curious thing is the spike at 2011 across all demographics. Is there a hypothesis?
Absent a compelling hypothesis I’d attribute it to sample wobble.
I click the link to the Intelligence journal and the first pop up is “Use the Science Direct AI to find papers faster.” AI is everywhere. Even though its making us stupider the big players wont stop because they’re hoping to become trillionaires. We are living in science fiction movie. VCs should test founders for antisocial personality traits before giving them funding.
I think that as more data emerge, this trend will simply confirm what we know intuitively and experientially to be true. Anyone who engages with this age group, e.g. teachers, has noticed the change, and it’s not encouraging.
Does a calculator degrade our math skills?
Yes. And I’m a licensed civil engineer. Previous generations had to memorize sin / cos/ tan charts and could do those calculations without a calculator. We can do more with a calculator than we can without it, but our raw skills definitely degrade with the use of a calculator.
After I read the premise of this study I knew what the answer was before I read on. People don’t use their brains for figuring out problems anymore, they just use a computer or a calculator, and now AI just does everything for you. People don’t know how to do anything anymore.
I was at a Panera store one time about 2011, I ordered the salad and the bill was about $10.38. I handed the girl a $20 bill, but the register was broken. In my head I can quickly deduce the money due back was $9.62. I knew this because growing up in the ’60s and 70s we didn’t use a calculator to do our basic math skills, we use pencil paper in our brains . She had to bring out a calculator to figure out the difference. I knew right then and there we were in big trouble.
Considering IQ drops as we get older I wonder what this looks like when stratified by age?