Why IQ levels are falling
Study shows young people’s intelligence scores have been dropping since the 1990s

The IQ levels of young people have been steadily falling for the past few decades, according to new research.
The decline is believed to have begun following the generation born in 1975, and indicates that the slow rise in intelligence observed over much of the 20th century has come to an end, says The Times.
Average IQs had risen by roughly three percentage points every decade since the Second World War, in a poorly understood trend known as the Flynn effect.
Subscribe to The Week
Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

Sign up for The Week's Free Newsletters
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
However, the new study, by Norwegian researchers, found that men’s IQs are measurably lower today than the scores of their fathers at the same age. Ole Rogeberg and Bernt Bratsberg, of the Ragnar Frisch Centre for Economic Research in Oslo, analysed the scores from a standardised IQ test taken by more than 730,000 Norwegian men who reported for national service between 1970 and 2009.
The results, published in the journal Proceedings of the National Academy of Sciences of the United States of America, or PNAS, show that those born in 1991 scored about five points lower than those born in 1975.
“This is the most convincing evidence yet of a reversal of the Flynn effect,” said Stuart Ritchie, a psychologist at the University of Edinburgh who was not involved in the research. “If you assume their model is correct, the results are impressive, and pretty worrying.”
The reasons for the Flynn effect and its apparent reversal are disputed. “Scientists have put the rise in IQ down to better teaching, nutrition, healthcare and even artificial lighting,” says The Times.
But “it is also possible that the nature of intelligence is changing in the digital age and cannot be captured with traditional IQ tests”, adds the newspaper.
An international study at the end of last year pointed towards the onset of technology as hindering the development of young people.
Researcher Michael Shayer, who co-authored the report, told Euronews that since 1995 a “large social force has been interfering with children’s development of thinking, getting larger each year”.
This “social force” includes the development of technology, such as game consoles and smartphones, “which have altered the way that children communicate with each other”, he explained.
“Take 14-year-olds in Britain. What 25% could do back in 1994, now only 5% can do,” Shayer added, citing maths and science tests.
Robin Morris, professor of neuropsychology at King’s College London, told The Times that IQ scores probably had hit a ceiling in the West, but there was not yet any reason to be unduly concerned.
“I think the reverse Flynn effect is real but would urge caution about generalising based on one sample,” he said. “Probably the tailing off is a general effect in high-income countries in which the contributor factors generally stabilise.”
Sign up for Today's Best Articles in your inbox
A free daily email with the biggest news stories of the day – and the best features from TheWeek.com
-
Why Russia removed the Taliban's terrorist designation
The Explainer Russia had designated the Taliban as a terrorist group over 20 years ago
By Justin Klawans, The Week US
-
Inside the Israel-Turkey geopolitical dance across Syria
THE EXPLAINER As Syria struggles in the wake of the Assad regime's collapse, its neighbors are carefully coordinating to avoid potential military confrontations
By Rafi Schwartz, The Week US
-
'Like a sound from hell': Serbia and sonic weapons
The Explainer Half a million people sign petition alleging Serbian police used an illegal 'sound cannon' to disrupt anti-government protests
By Abby Wilson
-
The arrest of the Philippines' former president leaves the country's drug war in disarray
In the Spotlight Rodrigo Duterte was arrested by the ICC earlier this month
By Justin Klawans, The Week US
-
Ukrainian election: who could replace Zelenskyy?
The Explainer Donald Trump's 'dictator' jibe raises pressure on Ukraine to the polls while the country is under martial law
By Sorcha Bradley, The Week UK
-
Why Serbian protesters set off smoke bombs in parliament
THE EXPLAINER Ongoing anti-corruption protests erupted into full view this week as Serbian protesters threw the country's legislature into chaos
By Rafi Schwartz, The Week US
-
Who is the Hat Man? 'Shadow people' and sleep paralysis
In Depth 'Sleep demons' have plagued our dreams throughout the centuries, but the explanation could be medical
By The Week Staff
-
Why Assad fell so fast
The Explainer The newly liberated Syria is in an incredibly precarious position, but it's too soon to succumb to defeatist gloom
By The Week UK