Researchers have documented a reversal of the Flynn effect, the long-term rise in average IQ and cognitive performance observed across generations for roughly 200 years.
For the first time in modern history, Generation Z shows lower performance than previous generations in several cognitive domains despite more years of formal education.
Neuroscientist Dr. Jared Cooney Horvath testified before the U.S. Senate Committee on Commerce, Science, and Transportation on January 15, 2026, linking the shift to widespread classroom screen use.
The Flynn Effect and Its Reversal
The Flynn effect refers to steady gains in IQ scores of about three points per decade in the 20th century, attributed to better nutrition, health, and access to education.
International assessments reflect the pattern. PISA 2022 results recorded significant drops in mathematics, reading, and science across OECD countries compared to prior cycles, with declines beginning around the mid-2000s and accelerating post-2010.
Horvath Senate Testimony
In written testimony submitted on January 15, 2026, Dr. Horvath stated that cognitive development in children across much of the developed world has stalled or reversed over the past two decades.
He highlighted evidence from PISA, TIMSS, and meta-analyses showing that higher classroom screen exposure correlates with weaker outcomes in reading, math, science, and higher-order reasoning. Horvath described a “structural mismatch” between human cognition, which evolved for deep focus and face-to-face interaction, and digital platforms designed for fragmented attention.
Teens now spend almost half their waking hours on screens, with substantial portions of that time during school hours on computers or tablets. Studies indicate students are often off-task for significant portions of device-based instructional time.
Broader Data and Context
Meta-analyses of educational technology show small or negative effect sizes for general learning outcomes when compared to traditional instruction, particularly for one-to-one device programs and online learning. Narrow, constrained tools for repetitive practice sometimes show modest benefits, but broad classroom integration frequently underperforms standard methods.
U.S. and international test data, including NAEP and TIMSS, show pre-pandemic declines in key subjects among younger students, with further declines after 2019.
What the Reversal Means in Practical Terms
The shift occurs even as students spend more time in school, suggesting that reduced educational access is not the cause.
Moving Forward
Dr. Horvath and other researchers call for evidence-based standards for educational technology, including independent efficacy trials before large-scale deployment. Policy recommendations include mode-equivalence validation for digital assessments, stronger data protections for students, and guidelines limiting non-essential screen exposure in early education.
No consensus exists on all contributing factors. Researchers continue to examine the roles of digital device use, instructional methods, and other environmental variables. Longitudinal studies remain ongoing to track impacts on future workforce skills and societal outcomes.
