As a global average, has Human Intelligence already peaked?
For more than a century, every generation has outperformed the last on standardised tests of literacy, numeracy and general reasoning. That upward curve is one of the quiet success stories of modern schooling. Now, however, a growing body of evidence suggests the trend has stalled and, in some places, reversed. How worried should we (society) be?
In written testimony to the US Senate this year, neuroscientist Dr Jared Cooney Horvath argued that Gen Z may be the first modern generation to underperform their parents on “basically every cognitive measure we have”, including attention, memory, literacy, numeracy and executive function.
Your employees know the truth. Does your EVP? At Fathom we measure the "Credibility Gap" between your promise and their reality.
Horvath links that shift to a simple timing problem. Around 2010, school systems across the developed world went all in on laptops, tablets and SaaS. At the same time, teenagers’ out-of-school lives moved onto smartphones and social apps. Since then, he argues, cognitive scores have flatlined or fallen, even as time in formal education has risen.
The claim is provocative, and not all researchers accept “Gen Z is dumber” headlines as settled science. But it sits on top of more mainstream trend lines that are getting hard to ignore.
What the data actually shows about falling scores
Several large assessment programmes tell a similar story.
In the United States, the National Assessment of Educational Progress (NAEP) long-term trend data for nine-year-olds showed a 5-point drop in reading and 7-point drop in maths between 2020 and 2022. It was the largest reading decline since 1990 and the first ever decline in maths since the assessment began in the 1970s.
By 2024, US twelfth-grade students recorded their lowest scores on national reading and maths tests in decades. Only around one in five were proficient in maths and about a third in reading, with performance slipping even at the “basic” level.
Internationally, the OECD’s PISA 2022 cycle reported an “unprecedented drop” across participating countries: average maths performance fell by nearly 15 points and reading by around 10 points compared with 2018.
Covid-19 disruption and chronic absenteeism have clearly compounded the problem. No serious researcher claims touchscreens alone broke maths. But the timing and pattern of declines, particularly in high-income countries that pushed hardest on classroom tech, has shown concerning correlations between screen-based learning and worsening learning outcomes.
Screens in schools: distraction by design
It’s also clear that “unregulated, leisure-style screen use in class is bad for learning”. Not just distracting students eyes away from learning materials, but even having a phone in a pocket can be a bigger distraction than most would believe.
The OECD’s 2024 report Students, Digital Devices and Success found that:
- 59% of students across OECD countries said their attention in maths lessons was diverted by other students using digital devices.
- Students who reported being distracted by peers’ devices in at least some maths classes scored significantly lower in maths than those who were not distracted.

A separate analysis of PISA data reported that about 54% of students were distracted by others’ device use, and those students scored around 15 points lower in maths, roughly the equivalent of several months of learning.
Teachers back this up on the ground. A 2024 Pew Research Center survey found that 72% of US high school teachers see cellphone distraction as a major problem in their classrooms, far higher than in middle or elementary schools.
US school leaders share the concern. New federal data from the National Center for Education Statistics shows 77% of public schools now prohibit students from using cell phones during class, and more than half of leaders say phones hurt academic performance.
The effect is not just about attention in the moment. Recent reviews of “digital age” memory and screen use suggest that constant device multitasking erodes the ability to store and retain information deeply and may weaken sustained attention to detail. In other words, excessive smartphone use out side of school time can hinder performance in school.
EBN analysis: For employer audiences, the interesting line here isn't that “phones distract teenagers” - we already knew that. It is the suggestion that years of device-mediated learning look to be changing the underlying habits of attention and memory that later show up in the workplace.
The global phone backlash
Policymakers have noticed. UNESCO and other observers report that at least 79 education systems worldwide now restrict or ban smartphone use in schools, citing concerns about distraction, learning loss and privacy.
Recent moves include:
- Chile, which passed a law banning smartphones and smart devices during class in elementary and middle schools from 2026, following evidence that digital distractions were disrupting learning.
- Bolivia, which began its 2026 school year with a nationwide ban on cellphones in classrooms across public and private schools, explicitly framing the policy as a way to boost focus and reduce the pull of entertainment apps.
- France, where phone bans in lower secondary schools are already in place and lawmakers are debating an extension to high schools, building on early evidence of calmer atmospheres and more social interaction in phone-free campuses.
Several US states, including Florida, Indiana, Ohio and Virginia, have passed or are drafting “phone-free schools” laws, while New York’s governor has signalled support for a statewide ban.
Yet the story is not simply “screens out”. Estonia, one of Europe’s top performers in PISA maths, science and creative thinking, has taken the opposite tack. Rather than banning devices, it is rolling out personal AI accounts for older students as part of a national “AI Leap” initiative, arguing that the key is structured use and a focus on higher-order thinking, not memorisation.

The debate is shifting from “tech or no tech” to “what kind of tech, under what rules, serving which cognitive goals”. In an increasingly digital world, banning tech could be harmful to a digital education - policy making in this area is no easy feat.
AI as the ultimate cognitive offload
If smartphones take up too much cognitive bandwidth, throwing AI into the mix risks making thinking almost totally unnecessary.
Cognitive scientists call this “cognitive offloading”: using external tools to reduce mental effort. In the same way a calculator saves us from having to our sums in our head, or on a piece of paper, search engines and now AI is taking it to a whole other level.
A recent review of smartphone use concluded that heavy reliance on phones for information retrieval, navigation and everyday decisions encourages people to depend on devices rather than internal cognitive processes, diminishing intrinsic memory and problem-solving capacity over time.
Emerging work on AI assistants suggests a similar pattern. A 2025 article in Frontiers in Psychology argues that delegating more tasks to AI can either free up mental bandwidth for complex thinking or encourage “cognitive laziness”, depending on how systems are used and what kinds of tasks are offloaded.
In other words, if students and early-career workers use AI to explore ideas, debate alternatives and check reasoning, it may aid deeper learning. If they use it to avoid struggle entirely, it can actually hollow out the very skills employers say they need most.
From classroom trends to candidate pools
Employers are already seeing signs of strain. Surveys of hiring managers and HR leaders consistently highlight gaps not in technical knowledge, but in areas like communication, collaboration, critical thinking and attention to detail. A 2024 analysis cited by HR Daily Advisor found recent graduates ranking lower than other workers on these soft skills, including strategic and critical thinking.
The National Association of Colleges and Employers reports a persistent disconnect between how students rate their own career-readiness competencies and how employers rate them, especially on critical thinking, professionalism and teamwork.
On the demand side, the World Economic Forum’s Future of Jobs 2023 report puts “analytical thinking”, “creative thinking” and other high-order cognitive skills at the top of employers’ priority lists, and estimates that around 44% of workers’ core skills will be disrupted between 2023 and 2027.
So we have a workforce where:
- Basic academic and cognitive scores are declining for incoming cohorts in many countries.
- Employers say they cannot find enough people with the exact cognitive skills most at risk of digital erosion.
- AI tools are arriving that make it tempting to outsource those very skills at an even higher rate.
For talent leaders, alarm bells should be ringing. Campus recruiting, early-career programmes and leadership pipelines need to be fed with sharp young talent ready to learn the ropes and grow professionally... but are they becoming a dying breed?
The automation temptation
Against this backdrop, automation has a clear commercial appeal. Forecasts tied to the World Economic Forum suggest AI and related technologies could displace tens of millions of roles globally by 2030, with a heavy impact on routine cognitive work such as data processing, basic coding and standard content production.
A growing body of commentary notes that AI’s early impact is particularly strong on entry-level white-collar roles, the very roles traditionally used to grow future managers and leaders.
If the incoming talent pool looks less prepared on core cognitive dimensions, the business case to “automate instead of hire and train” becomes even stronger:
- Why invest in multi-year development of attention, reasoning and writing skills if AI can deliver all/most of the output immediately?
- Why build large (and expensive) graduate intakes if entry-level tasks are the first to be automated?
In the short term, those decisions can look rational. Over time they risk hollowing out the mid-career and senior layers that depend on people who have done the hard cognitive miles early on. For sectors already struggling with leadership succession, that is a serious structural risk.
Helping HR, talent acquisition, employer branding, and company culture professionals find careers worth smiling about.
What employers and EB leaders can do now
If the trend lines point to a smaller share of candidates with strong, self-developed cognitive skills, what can employers do that is not simply “hope schools fix it”?
A few practical levers are emerging.
1 - Hire for cognitive habits, not just credentials
If formal test scores and degrees are less reliable signals, selection needs to probe how candidates actually think:
- Use work samples and case exercises that require sustained attention, reasoning and writing, not just AI-prompting.
- Make it explicit when AI use is allowed or not, so you can see candidates’ unaided capabilities as well as their tool use.
- Include behavioural questions that surface habits around focus, deep work and distraction management.
This is already happening quietly in sectors like consulting and professional services. Expect it to spread.
2 - Treat cognitive skills as trainable infrastructure
Many employers still treat critical thinking, structured writing and attention control as “nice to have extras” rather than core hiring or on-the-job training areas.
Given the data, that seems outdated. Instead:
- Build foundational programmes in reasoning, evidence use, long-form writing and quantitative thinking into early-career pathways.
- Teach “AI-native” employees how to use tools as amplifiers rather than crutches, with explicit norms about when to switch them off.
There is a branding upside. A credible promise that “you will leave this company sharper than you arrived” is attractive in a world where people worry about their skills being commoditised.
3 - Acknowledge digital and AI hygiene
Younger workers know their phones are a problem. Teachers, doctors and now politicians are talking about it in public.
Employers who can say, concretely, “here is how we protect your focus and help you build real depth while using modern tools” will stand out:
- Clear policies on notification culture and meeting overload.
- Guardrails on AI use in sensitive tasks.
- Manager training on protecting focus time and modelling non-performative busyness.
This is increasingly part of wellbeing and productivity, but it is also a cognitive-health issue.
4 - Advocate upstream without oversimplifying
Finally, big employers have a voice in education debates. Using that voice to call simply for “more devices” or “pure tech bans” misses the nuance emerging from the research.
The evidence to date suggests:
- Moderate, structured use of digital tools tied tightly to pedagogy can support learning.
- Excessive or leisure-style device use in class is consistently linked with distraction and lower performance.
- Unguided reliance on digital tools, including AI, encourages cognitive offloading, which can either support or erode skills depending on design.
Responsible employer advocacy will reflect that nuance, pushing for environments that build long-term cognitive capacity rather than maximising screen exposure for its own sake.
The long view
Whether or not “peak human intelligence” has already passed, the combination of falling scores, saturated screens and ubiquitous AI is reshaping the supply side of the talent market.
If large employers respond primarily by automating entry-level work, they may get short-term efficiency at the cost of long-term cognitive depth in their organisations.
The alternative is harder and more expensive. It involves hiring for raw potential, training for thinking, and designing work and technology use so that people’s minds get sharper over time, not duller.
That choice, more than any eventual verdict on Gen Z’s test scores, could decide whether the next generation of leaders is equipped to tackle the problems AI cannot solve for them.
Takeaways
1. The “peak intelligence” story is really about stalled cognitive gains
For most of the twentieth century, each generation outperformed the last on core tests of reasoning, literacy and numeracy. The new research is not just saying “Gen Z is dumber”, it is highlighting a stall or reversal in those gains, especially in high-income countries that digitised classrooms fastest. That has long-term implications for how employers think about raw cognitive capacity in their future talent pool.
2. Global test scores are sliding, not just “post-Covid wobbling”
NAEP, PISA and other large assessments show some of the steepest declines on record in maths and reading. Covid disruption and absenteeism matter, but the pattern suggests deeper, systemic issues in how young people are learning and concentrating. Employers relying on degrees and grades as shorthand for “baseline capability” need to revisit those assumptions.
3. Screens in class are not neutral, they reshape attention and memory
The evidence is clearest where devices are used like leisure tech during lessons. High rates of distraction from phones and laptops in class correlate with lower maths and reading performance, and cognitive scientists are increasingly concerned about the effect of constant multitasking on deep memory and sustained attention. Years of learning in that environment show up later as patchy focus and shallow processing at work.
4. Governments are quietly admitting the experiment went too far
Dozens of countries and regions have moved to restrict or ban phones in schools, often citing learning loss and classroom disruption. At the same time, a few high performers are doubling down on structured, curriculum-aligned tech and AI. The political signal is clear: the “more screens everywhere” phase is ending, replaced by a harder conversation about what kinds of digital use actually build cognitive skills.
5. AI is the next big offload, and it can either sharpen or soften thinking
AI assistants make it easy to outsource not only memory, but also drafting, analysis and decision-making. Used well, they can free up mental bandwidth for higher-order thinking. Used as a shortcut to avoid struggle, they encourage what psychologists call “cognitive laziness” and can erode exactly the skills employers claim to prize: critical thinking, structured writing and judgement.
6. Employers are already feeling the cognitive squeeze in early-career hiring
Recruiters and hiring managers report that new graduates struggle less with tools and more with fundamentals: clear communication, reasoning with data, attention to detail, and working without constant digital distraction. That gap is surfacing in campus hiring, assessment centres and first-year performance, even in organisations with strong brands and competitive salaries.
7. Automation looks rational in the short term, but it hollows out the pipeline
If entry-level tasks can be automated faster than humans can be trained to do them well, the commercial temptation is obvious. The risk is that organisations quietly remove the very roles where people used to build cognitive “mileage” and operational judgement. That creates a future leadership problem, not just a headcount efficiency win.
8. Employer brands will be judged on how they grow, not just buy, cognitive strength
In a world of slipping scores and ever-present AI, strong brands will not just market flexible work and cool tools. They will show how they protect focus, teach deep thinking, and help people get sharper over time. That means hiring for cognitive habits, designing work that rewards depth, and setting explicit norms for when to lean on AI and when to think for yourself.
References
-
Dr Jared Cooney Horvath, testimony to US Senate Committee on Commerce, Science, and Transportation. Read the testimony on commerce.senate.gov (United States)
-
NAEP Long-Term Trend Assessment: 2022 Reading and Mathematics, Age 9. Read the NAEP 2022 highlights on nationsreportcard.gov (United States)
-
PISA 2022 Results (Volume I): The State of Learning Worldwide, OECD. Read the PISA 2022 results on oecd.org (Global)
-
OECD – Students, Digital Devices and Success. Read the report on oecd.org (Global)
-
Governing – Digitally distracted students have lower academic performance. Read the article on governing.com (United States)
-
Pew Research Center – 72% of US high school teachers say cellphone distraction is a major problem in the classroom. Read the analysis on pewresearch.org (United States)
-
National Center for Education Statistics (IES) – More than half of public school leaders say cell phones hurt academic performance. Read the release on ies.ed.gov (United States)
-
UNESCO – Smartphones in school: only when they clearly support learning. Read the article on unesco.org (Global)
-
AP News – Chile becomes latest country to ban smartphone use during class. Read the story on apnews.com (Chile)
-
AP News – Bolivia kicks off school year with ban on cellphones. Read the story on apnews.com (Bolivia)
-
Le Monde – France is considering banning phones in high schools. This school near Paris already does. Read the article on lemonde.fr (France)
-
VOA Learning English – US states push for cell phone ban in high schools. Read the story on voanews.com (United States)
-
The Guardian – Estonia eschews phone bans in schools and takes leap into AI. Read the article on theguardian.com (Estonia)
-
The Guardian – ‘These results are sobering’: US high school seniors’ reading and math scores plummet. Read the article on theguardian.com (United States)
-
AP News – US high school students lose ground in math and reading, continuing yearslong decline. Read the story on apnews.com (United States)
-
The Wall Street Journal – Twelfth-Grade Math and Reading Scores in U.S. Hit New Low. Read the article on wsj.com (United States)
-
The Times of India – Himachal Pradesh bans mobiles for students, teachers during school hours. Read the report on timesofindia.com (India)
-
Trends in Cognitive Sciences – Cognitive offloading (smartphones and external memory tools). Read the article on cell.com (Global)
-
Springer – Digital-age memory and screen use (book chapter). Read the chapter on link.springer.com (Global)
-
CJAST – Smartphone use, cognitive offloading and cognitive functioning. Read the article on journalcjast.com (Global)
-
Frontiers in Psychology – AI assistants, cognitive offloading and ‘cognitive laziness’. Read the article on frontiersin.org (Global)
-
HR Daily Advisor – Key workplace skills missing in 2024 graduates. Read the article on hrdailyadvisor.hci.org (United States)
-
National Association of Colleges and Employers – The gap in perceptions of new grads’ competency proficiency and resources to shrink it. Read the report on naceweb.org (United States)
-
World Economic Forum – The Future of Jobs Report 2023. Read the report on weforum.org (Global)
-
The Guardian – AI and the future of work (interactive on white-collar jobs). Explore the interactive on theguardian.com (Global)
-
The Post Millennial – Gen Z 1st generation to score worse on tests than their parents after textbooks replaced with $30 billion in laptops. Read the article on thepostmillennial.com (United States)




