Sharp IQ Decline Strikes U.S. Adults Aged 18–22 Most Severely

Cognitive Test Scores Trend Downward Across the United States

According to НВ — Техно: A new analysis of cognitive assessments taken by almost 400,000 American adults shows that average intelligence scores in the U.S. slipped steadily between 2006 and 2018. Researchers describe this downturn as a reversal of the Flynn effect-the long-observed rise in average IQ results that had been documented since the 1930s. The drop appeared across demographic lines, affecting both men and women, different age groups, and people with varying levels of education. The steepest losses were seen among adults between 18 and 22 years old and among test-takers with lower levels of education.

What the Data Show About Reasoning, Language, and Spatial Skills

The research looked at online cognitive test results from 394,378 participants ranging from 18 to 90 years old. The tests measured three areas:

• abstract and logical reasoning,
• verbal ability,
• spatial visualization.

Scores for abstract and logical thinking fell, while verbal ability remained largely stable. However, spatial reasoning improved, especially on tasks involving mental rotation of three-dimensional objects. Video games are sometimes suggested as an explanation for that improvement, though this idea remains speculative. Over the last decade, average scores on the ACT and SAT, two standardized U.S. college entrance exams, have also declined. This cognitive slide began before generative AI became widespread and before the COVID-19 pandemic struck.

The researchers stop short of identifying exact causes. British commentator James Marriott has proposed that the overall decline may be linked to a cultural shift from printed books to smartphones.

In sum, the findings point to major shifts in the cognitive abilities of Americans and raise fresh questions for future research.

These results could signal a need to reassess educational strategies and teaching methods across the United States. The downward trend may carry serious implications for the next generation. The findings also add to broader debates among educators and policymakers about how technology, daily habits, and learning environments shape mental performance. Understanding the root causes could help identify ways to boost intellectual development in young people and lift national educational outcomes.

As cognitive abilities continue to decline among young adults, it's essential to explore factors that may influence mental acuity. For instance, research indicates that bilingualism can significantly enhance brain function, potentially offsetting some cognitive decline. Understanding these connections could provide insights into reversing current trends and improving mental performance.