The Claim That Gen Z Is “Less Cognitively Capable” Than Their Parents Doesn’t Hold Up

A widely shared claim holds that Generation Z is the first generation to end up less cognitively capable than its parents. The idea gained traction after neuroscientist Dr. Jared Cooney Horvath told the U.S. Senate that decades of rising cognitive performance had plateaued and reversed.[1]

There is a problem with that claim: the IQ studies most often cited to support it did not actually measure Generation Z. The central source is a 2016 systematic review of “negative Flynn effect” studies—the reversal of the long-running rise in cognitive test scores known as the Flynn Effect.[2] [3]

The studies gathered in that review tested people born no later than about 1994. Most definitions, including Pew Research Center’s, place the start of Generation Z around 1997. That means the research being used to describe Gen Z was, in fact, measuring older Millennials and, in several cases, Generation X.[4]

This is not a technicality. If a body of studies does not include the generation it is being used to describe, it cannot tell us whether that generation is experiencing the trend. And several of the studies pointed in a different direction entirely: Norwegian and Danish military-conscript data show declines among men born from the late 1970s into the mid-1980s, and the British adolescent studies place their later cohorts in the early-to-mid 1990s—Generation X and Millennials, not Gen Z.[5]

There is a further reason for caution. The 2016 review has drawn scrutiny beyond the question of whom it measured. A university research-integrity investigation found that one paper cited in the review contained plagiarism, an issue later addressed through a published corrigendum.[6] And one of the review’s co-authors compiled widely circulated national-IQ datasets that scholarly bodies have criticized for unrepresentative samples and other validity problems—datasets a major academic publisher has since said it is reviewing.[7] Such concerns do not automatically invalidate every finding, but they make careful scrutiny essential before broad conclusions are drawn.

The underlying worry is reasonable. Parents are right to be concerned about the educational and mental-health impact of unregulated device use. They are right to want policymakers to investigate and, where warranted, to act. They are right to ask which tools are used in the classroom and whether those tools actually advance learning. And they are right to want policy grounded in evidence rather than in a compelling clip.

Education policy should be informed by reliable evidence and accurate information, candidly presented to parents, policymakers, administrators, teachers, and the public alike. Discussions driven by catchy but unfounded claims make for bad policy. Our children and our students deserve better.

Want to go deeper? We've published a companion piece that examines the research Jared Horvath continues to cite on screen time and where it diverges from the broader evidence base. Read the full breakdown here.