A recent study revealed that the IQ scores of young adults have been declining in the past few decades.
According to a study published by researchers from the Ragnar Frisch Centre for Economic Research in Oslo in the journal Proceedings of the National Academy of Sciences, the IQ scores of humans have been falling for decades now.
The intelligence decline is believed to have begun after the generation born in the 1970s. This indicates that the rise in humans’ intelligence quotient observed at the beginning of the 20th century has finally come to an end.
Known as the Flynn Effect, it was said that the average IQ of young adults has risen by about three percent every decade since the Second World War. However, this trend has not been fully explored and studied, providing scientist with little information about the Flynn Effect.
According to the new study, the IQ of men today is measurably lower than those of their fathers at the same age. Using the scores from a standardized IQ test taken by over 730,000 Norwegian men ages 18 to 19 years old who have served in the military between 1970 and 2009, the researchers were able to find that people born in 1991 scored less than five points than those born in 1975.
“This is the most convincing evidence yet of a reversal of the Flynn effect,” Stuart Ritchie, a psychologist from the University of Edinburg who was not involved in the study, said. “If you assume their model is correct, the results are impressive and pretty worrying.”
The results of the study showed that the turning point for the Flynn Effect occurred for children born around 1975.
This is not the first time that a dip in human IQ scores has been observed. In fact, James Flynn himself looked at the IQ scores of British teenagers nearly a decade ago and found a similar falling trend.
“It looks like there is something screwy among British teenagers,” Flynn said. “While we have enriched the cognitive environment of children before their teenage years, the cognitive environment of the teenagers has not been enriched.”
Further investigation into the matter led researchers to believe that the primary cause of the IQ decline is not the shift in demographic factors.
Instead, rapid changes in lifestyle are potentially behind these lower IQs. Some experts are also suggesting that the IQ tests were not updated to quantify and estimate our current intelligence accurately.
At the moment, further studies are required to identify what causes the Flynn Effect reversal entirely.