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IQ test scores have been in free fall since the 1970s: are we less intelligent? The growth reported during the twentieth century has reversed: are we all becoming stupider, or rather is this tool, which perhaps should be considered outdated?
The increase in the level of IQ between one generation and another recorded during the 1900s is officially over. Analysis of the results of 730,000 IQ tests taken in Norway reveals that scores have been declining since the mid-1970s, and attempts to provide some possible explanations for the decline.
The study published in the Proceedings of the National Academy of Sciences raises what is known as the Flynn Effect among those who deal with intelligence and demographic trends. Around the 1980s, the New Zealand researcher James R. Flynn observed how, in the first part of the century, the global average value of intelligence, assessed through IQ tests, had grown linearly, increasing by approximately 3 points for each decade.
Momentum exhausted. From the new analysis conducted by scientists at the Ragnar Frisch Center for Economic Research in Norway, it emerges that this effect reached its peak in the mid-1970s, and then began to decline. The team acquired the results from IQ tests of 730 thousand Norwegian 18-19 year olds being evaluated for compulsory military service. From 1970 to 2009, three generations of young men, born between 1962 and 1991, were recruited. Among those born after 1975, there was a drop in average scores of 7 points for each generation. The result confirms some other studies, partly conducted by Flynn himself on British teenagers.
