I was sitting in my office in January 2026 when neuroscientist Jared Cooney Horvath told the United States Senate something that made headlines around the world: “Our kids are less cognitively capable than we were at their age.”
Within days, a tweet from World of Statistics on February 6 turned the story into a global firestorm. Fortune, VICE, Newsweek, and dozens of international outlets ran variations of the same headline: Gen Z is the first generation in modern history to score lower than the previous one. The story went viral because it confirmed something millions of parents, teachers, and employers had sensed but could not prove. Something felt different about this generation’s cognitive habits. And now there were numbers to back it up.
But here is what the headlines missed, and what I want to spend this article carefully unpacking: the data is real, the decline is measurable, and it is far more nuanced than “kids are getting dumber.”
As someone who has administered thousands of cognitive assessments across three decades, I can tell you that what the research actually shows is both more alarming and more hopeful than either the panic or the dismissal would suggest. The alarm is warranted because the declines are consistent across multiple countries, multiple studies, and multiple cognitive domains. The hope is warranted because the causes appear to be entirely environmental, which means they are reversible.
Let me walk you through the evidence.
The Data That Started the Firestorm
To understand what Horvath told the Senate, you need to understand what he was actually citing.
His testimony drew on a convergence of evidence from three major sources. The first is the Programme for International Student Assessment, known as PISA, administered every three years to fifteen-year-olds in over eighty countries by the Organisation for Economic Co-operation and Development. PISA 2022 results, released in December 2023, showed the largest single-cycle decline in mathematics performance ever recorded: an average drop of roughly 15 points across OECD countries, equivalent to three-quarters of a year of schooling lost. Reading scores fell by 10 points. Science scores dropped comparably. These were not marginal changes. They represented the steepest decline in the assessment’s twenty-three-year history.
The second source is the IEA’s Progress in International Reading Literacy Study, or PIRLS. The 2021 results showed declining fourth-grade reading scores in the majority of participating countries compared to 2016, eroding gains that had taken years to build. Critically, the data showed a consistent pattern: students who spent more time using digital devices for schoolwork and leisure scored lower on reading comprehension, even after controlling for socioeconomic status.
The third and perhaps most scientifically rigorous source is the growing body of research on what psychologists now call the Reverse Flynn Effect.
The Reverse Flynn Effect: A Century of Progress, Reversed
For most of the twentieth century, human IQ scores rose relentlessly. James Flynn documented this phenomenon in 1984: approximately three points per decade, totaling roughly 30 points over the century. Better nutrition, expanded education, reduced exposure to neurotoxins like lead, smaller family sizes, and increasing environmental complexity all contributed to what became known as the Flynn Effect. By modern scoring standards, the average person in 1900 would have scored around 70 on a contemporary IQ test.
Then, around the mid-1990s, the trend began to reverse.
The earliest and most rigorous evidence came from Scandinavian military conscription data. Bratsberg and Rogeberg’s landmark 2018 study in Proceedings of the National Academy of Sciences analyzed scores from 736,808 Norwegian conscripts and found that IQ scores peaked for men born around 1975 and declined thereafter. Their within-family design, comparing brothers raised by the same parents, ruled out immigration, differential fertility, and genetic explanations. Both the original rise and the subsequent reversal were environmental in origin.
Similar reversals have now been documented in Denmark, Finland, France, the Netherlands, Estonia, Britain, and Australia. The pattern is remarkably consistent: IQ scores in wealthy, developed nations peaked for cohorts born in the 1970s to mid-1990s and have declined since.
In the United States, the most comprehensive evidence comes from Elizabeth Dworak and colleagues at Northwestern University. Their 2023 study, published in the journal Intelligence, analyzed cognitive test data from 394,378 American adults collected between 2006 and 2018. They found declines in verbal reasoning, matrix reasoning, and letter-and-number series performance. The declines were consistent across age groups, genders, and education levels. Only one domain, spatial reasoning (the ability to mentally rotate three-dimensional objects), showed improvement.
The magnitude of these declines varies by study and country, but the estimates converge around 2 to 5 points per decade, roughly the mirror image of the original Flynn Effect’s gains. What took a century to build appears to be eroding in a generation.
What Horvath Actually Said (And What the Headlines Distorted)
Horvath’s Senate testimony was more nuanced than the media coverage suggested. He was not claiming that Gen Z is biologically less intelligent than previous generations. He was making a specific, evidence-based argument about the relationship between educational technology, cognitive habits, and measurable cognitive outcomes.
His core claims, supported by the data he presented:
Gen Z is underperforming previous generations in multiple cognitive domains, including attention, memory, executive function, literacy, numeracy, and overall IQ. This pattern began around 2010, coinciding with the rapid expansion of digital technology into classrooms and daily life. Despite spending more time in school and having unprecedented access to information, Gen Z test scores have stagnated or declined.
There is a strong correlation between time spent on computers in school and lower academic performance. Students who used computers for approximately five hours per day in educational settings scored more than two-thirds of a standard deviation lower on reasoning, literacy, and numeracy tests compared to students with minimal classroom technology exposure.
The mechanism, Horvath argued, is not that technology itself is harmful but that the way it has been deployed in education fundamentally conflicts with how human brains learn. “Humans are biologically programmed to learn from other humans and from deep study,” he testified, “not flipping through screens for bullet point summaries.” Learning, he emphasized, requires sustained attention, cognitive effort, and the kind of productive struggle that screens are designed to eliminate.
As Horvath wrote in his own follow-up analysis: the media saw a chance to “dunk on teenagers,” but the real story is about what adults did to the learning environment, not about any deficiency in the teenagers themselves.
“Brain Rot”: From Meme to Medical Concern
The cultural anxiety surrounding Gen Z’s cognitive health has crystallized around a single term that was named Oxford’s Word of the Year for 2024: “brain rot.”
Usage of the term increased by 230 percent in 2024 alone. Originally internet slang for the feeling of cognitive deterioration from consuming too much low-quality digital content, “brain rot” has migrated from TikTok meme to serious scientific discussion. A March 2025 review published in Brain Sciences formally examined the phenomenon, and a February 2026 paper in Current Psychiatry Reports explored its clinical implications.
The science behind the cultural anxiety is more complicated than either camp acknowledges.
On one hand, there is robust evidence that certain patterns of digital media use are associated with reduced attention span, impaired working memory, and lower academic performance. A 2024 meta-analysis found that heavy social media use was associated with poorer sustained attention and increased susceptibility to distraction. The mechanisms are plausible: short-form video content rewards rapid attention switching, while deep learning requires exactly the opposite cognitive posture.
On the other hand, the relationship between technology use and cognitive outcomes is not uniformly negative. A joint study from the University of New South Wales published in 2025 found no evidence that technology causes “digital dementia” in older adults, and some forms of digital engagement, particularly those involving active problem-solving, social interaction, and information seeking, were associated with preserved or even enhanced cognitive function. The issue appears to be not screens per se, but the kind of cognitive activity screens facilitate. Passive consumption of short-form content is associated with poorer outcomes. Active, effortful engagement with complex digital material is not.
This distinction matters enormously for how we think about the Gen Z IQ story. The problem is not that young people use technology. The problem is that the dominant forms of technology use, endless scrolling, short-form video, auto-summarization, and constant multitasking, train the brain in cognitive habits that are the precise opposite of what IQ tests measure: sustained attention, effortful reasoning, and deep processing of complex information.
The Uncomfortable Question: Are IQ Tests Measuring the Right Things?
Before we conclude that an entire generation is cognitively compromised, we need to ask a question that most coverage of this story has ignored: is the decline in IQ scores actually measuring a decline in intelligence, or is it measuring a shift in the kind of intelligence that modern environments develop?
Elizabeth Dworak, the lead author of the Northwestern study, has been remarkably careful on this point. “It doesn’t mean their mental ability is lower or higher,” she told Northwestern’s press office. “It’s just a difference in scores that are favoring older or newer samples. It could just be that they’re getting worse at taking tests or specifically worse at taking these kinds of tests.”
This is not a trivial caveat. IQ tests measure specific cognitive skills: the ability to reason verbally, to identify abstract patterns, to hold and manipulate information in working memory, to process information quickly. These skills are genuine and important. But they are not the totality of human intelligence, and they are heavily influenced by the cognitive habits that environments encourage.
Consider that spatial reasoning, the one domain where scores are rising, is precisely the kind of cognitive ability that heavy technology use might develop. Navigating complex visual interfaces, playing video games that require rapid spatial processing, and engaging with three-dimensional digital environments all exercise spatial cognition. If IQ tests weighted spatial reasoning more heavily, the narrative might be “Gen Z is getting smarter,” which would be equally misleading.
The more accurate interpretation, and the one I use in my clinical practice, is that the cognitive profile of young people is changing. Some abilities are declining. Others are holding steady or improving. The net effect on IQ test scores is negative because the tests were designed in an era that valued the kinds of cognitive habits that sustained, deep, offline engagement develops. Whether this shift represents genuine cognitive decline or cognitive recalibration is a question that the data alone cannot answer.
What Is Actually Causing the Decline?
The honest scientific answer is: we do not know with certainty, but the evidence points to a combination of environmental factors that have converged over the past two decades.
Screen time and digital media are the most frequently cited culprits, and the correlational evidence is strong. OECD data consistently shows that beyond moderate levels, more technology use in education correlates with lower test scores. Horvath’s testimony emphasized that paper reading produces better comprehension than screen reading, and handwriting produces better learning outcomes than typing. These findings are well-replicated. The mechanism involves depth of processing: screens encourage skimming and rapid switching, while paper and handwriting force slower, more effortful engagement.
But screen time is almost certainly not the whole story. The Reverse Flynn Effect began in Scandinavian countries in the 1990s, before smartphones existed and before social media was a factor. This suggests that screens accelerated an existing trend rather than creating it from scratch.
Other proposed contributors include changes in educational emphasis, a shift toward standardized testing and STEM focus that may have reduced time spent on activities that develop verbal reasoning and abstract thinking. Nutritional factors, including the increasing prevalence of ultra-processed food in young people’s diets, have been linked to poorer cognitive outcomes in emerging research. Reduced sleep, with adolescents consistently getting less sleep than previous generations, directly impairs the cognitive functions that IQ tests measure. Environmental pollutants, including microplastics and endocrine disruptors, are being investigated as potential contributors to cognitive decline, though the evidence remains preliminary. And COVID-19 learning disruption, which removed students from structured educational environments for one to two years during critical developmental windows, almost certainly compounded existing trends.
The most likely explanation is that no single factor is responsible. Rather, a constellation of environmental changes has shifted the cognitive landscape in ways that make the specific skills IQ tests measure harder to develop and maintain.
What This Means for You
If you are a member of Gen Z reading this article, I want to be very direct: this data does not mean you are less intelligent than your parents. It means the environment you grew up in developed certain cognitive skills less effectively than the environments previous generations experienced, while likely developing other skills that IQ tests do not measure. Your brain is not broken. Your cognitive habits may need recalibration.
If you are a parent, teacher, or employer worried about these trends, the research points toward concrete, actionable responses. Reducing passive screen time and replacing it with active, effortful cognitive engagement is the single most evidence-supported intervention. Restoring deep reading, extended writing, and sustained problem-solving to educational curricula addresses the specific skills that are declining. Protecting sleep, particularly for adolescents, restores the consolidation processes that convert learning into lasting memory.
And if you are simply curious about where you stand, there is genuine value in that curiosity. One of the most consistent findings in cognitive psychology is that metacognitive awareness, knowing your own cognitive strengths and weaknesses, is itself a powerful predictor of effective intellectual functioning. Taking a well-designed IQ test is not about labeling yourself with a number. It is about understanding your cognitive profile: where you excel, where you might benefit from deliberate practice, and how your individual pattern compares to population norms.
The Generational IQ Comparison: Where Do You Fall?
To put the current decline in perspective, here is what the data tells us about generational IQ trajectories.
The Silent Generation (born 1928 to 1945) grew up during the steepest phase of the original Flynn Effect. Their cognitive scores, measured during their youth, were significantly lower by modern standards but represented a substantial leap over their parents’ generation.
Baby Boomers (born 1946 to 1964) benefited from expanded education, improved nutrition, reduced lead exposure, and postwar prosperity. Their generation saw some of the largest IQ gains in recorded history.
Generation X (born 1965 to 1980) continued the upward trend, though gains began to slow in some countries. They represent the approximate peak of the Flynn Effect in many Western nations.
Millennials (born 1981 to 1996) straddle the inflection point. Early Millennials likely benefited from the last gains of the Flynn Effect. Later Millennials may have begun experiencing the plateau or early reversal.
Generation Z (born 1997 to 2012) appears to represent the first full cohort to fall on the declining side of the curve. The Bratsberg and Rogeberg data from Norway, the Dworak data from the United States, and the PISA international assessments all converge on this conclusion. The estimated decline, approximately 2 to 5 points compared to peak cohorts, is statistically significant and practically meaningful, even if it does not justify the more sensational headlines.
Generation Alpha (born 2013 onward) remains to be seen. If the environmental factors driving the decline intensify, further drops are plausible. If corrective measures, including screen time reduction in schools, restoration of deep reading practices, and improved sleep hygiene, are implemented at scale, the trend could reverse. The Flynn Effect itself proves that IQ responds powerfully to environmental improvement. There is no reason the same mechanism cannot work in the upward direction again.
The Deeper Question: What Kind of Intelligence Are We Building?
The Gen Z IQ story is ultimately not about one generation being smarter or dumber than another. It is about a fundamental shift in the cognitive demands of modern environments and the skills those environments develop.
Every generation’s intelligence reflects the world it was shaped by. The generation that grew up reading books for hours developed extraordinary verbal reasoning. The generation that grew up solving mechanical problems developed strong spatial skills. The generation that grew up navigating complex social media landscapes may be developing forms of social intelligence, information filtering, and rapid pattern recognition that existing IQ tests simply do not capture.
The danger is not that intelligence is disappearing. The danger is that the specific cognitive skills that support deep thinking, sustained analysis, complex reasoning, and careful judgment are receiving less practice than they once did, and those are precisely the skills that predict success in the most consequential domains of life: scientific discovery, medical diagnosis, legal reasoning, strategic planning, and wise decision-making.
Those skills can be rebuilt. The brain’s neuroplasticity does not disappear because you grew up with a smartphone. But rebuilding them requires deliberate effort, the same kind of effortful, uncomfortable, sustained cognitive engagement that Horvath described to the Senate.
What the Research Says You Can Do Right Now
Based on the converging evidence from the studies discussed in this article, here are the most evidence-supported strategies for protecting and strengthening the cognitive abilities that the Reverse Flynn Effect appears to be eroding.
Read on paper. Multiple studies confirm that reading comprehension and retention are superior with physical text compared to screens. This is not nostalgia. It is neuroscience. The tactile, spatial, and attentional properties of paper reading engage deeper processing than screen reading.
Write by hand. Research consistently shows that handwritten notes produce better learning outcomes than typed notes. The slower pace forces more active processing, summarization, and engagement with the material.
Practice sustained attention. Any activity that requires you to focus on a single complex task for thirty minutes or more without switching, whether it is reading a challenging book, working through a math problem, learning an instrument, or engaging in deep conversation, exercises the precise cognitive muscles that IQ tests measure and that modern environments are undertrained.
Protect your sleep. Seven to nine hours for adults, eight to ten for adolescents. Sleep is when the brain consolidates learning, clears metabolic waste, and restores the working memory capacity that supports next-day cognitive performance. There is no supplement, app, or brain training program that can substitute for adequate sleep.
Limit passive scrolling. The distinction is not between “screen time” and “no screen time.” It is between passive consumption, which trains rapid attention switching and shallow processing, and active engagement, which supports learning. Watching a documentary and taking notes is cognitively different from scrolling through thirty-second clips for an hour, even though both involve screens.
And test yourself. Not because a number defines you, but because understanding your cognitive profile gives you actionable information. If your IQ score falls in a particular range, knowing what that range means for your processing speed, verbal reasoning, and abstract thinking helps you make better decisions about how to study, work, and develop your abilities.
Final Thoughts
The Gen Z IQ story is not a story about a broken generation. It is a story about what happens when environments change faster than our understanding of what those environments are doing to cognition.
For a century, the Flynn Effect told us something extraordinary: that improving environments reliably improve cognitive performance at scale. The Reverse Flynn Effect tells us the corollary: that degrading the cognitive demands of environments reliably degrades the cognitive skills those environments once built.
Gen Z did not choose to grow up in front of screens. They did not choose to have deep reading replaced by skimming, handwriting replaced by typing, sustained attention replaced by constant notification, or effortful learning replaced by auto-summaries. Adults made those choices for them, often with the best of intentions and the worst of outcomes.
The encouraging news, the news buried beneath the sensational headlines, is that everything the Flynn Effect taught us about upward cognitive change remains true. Intelligence responds to environment. Skills respond to practice. Brains respond to demands. If we change the demands, we change the outcomes.
The question facing every generation, not just Gen Z, is whether we will choose to make those changes. Whether we will prioritize depth over speed, effort over convenience, sustained thought over constant distraction.
Your IQ is not your destiny. But understanding where it stands, what it means, and what shapes it, that is the beginning of taking control of your own cognitive future.
