Tuesday 16 July 2019

Patricia Casey: Why IQs are falling and why this cannot be ignored

Dr Patricia Casey
Dr Patricia Casey
Brain decline: environmental factors are at play

Patricia Casey

Maybe I'm stupid too, but I had no idea that our IQs (intelligence quotients) are declining. This finding received considerable media coverage in the past week. The reported change in IQ is not specific to us in Ireland, since no such studies have been carried out here. Across the globe, from Scandinavia to Korea, intelligence is now going backwards, apparently. Until recently, there had been evidence that it was increasing.

The gradual increase in IQ is referred to as the Flynn Effect, named after James R. Flynn, from the University of Otago in New Zealand. It was he who identified an increase in the intelligence test scores across Europe and many parts of the world over the 20th century. He demonstrated that IQ increased by three points every decade from 1950 to the 1980s.

But this trend is now in reversal, according to a number of studies. The most recent study from the Ragnar Frisch Centre for Economic Research in Norway analysed IQ tests scores of 730,000 individuals and it has shown that the Flynn effect reached its apogee for those born in the 1970s and that it has declined in subsequent birth cohorts.

The source of this data was from 18- and 19-year-old Norwegian men who took these tests as part of their compulsory military service between 1970 and 2009. They were born between 1962 and 1991. Flynn himself, in a study of British teenagers a decade ago, found a similar fall.

The idea that people were becoming less intelligent was captured in the movie Idiocracy in 2006. This comedy has become something of an icon for those who point to the dumbing down of social and political debate. According to the New Scientist, it is the comedy that became a documentary.

The findings in the Norwegian study are not new. Other researchers, from China to Australia, Brazil and Denmark have identified similar patterns.

For example, one test, the Raven's Progressive Matrices, was used initially in 1942 and the points score rose by 14 points between the first testing and a later one in 2008.

Tests such as these are upgraded regularly to take account of simple things such as alterations in the words we use. They are then standardised against the older versions and psychometricians developing them have found that students scoring the average of 100 on the new tests, scored higher in the older ones.

Why might IQ be declining? For many decades, researchers thought that intelligence was inherited and that those with high IQs produced children who were also bright.

Likewise, those who had low IQs were believed to not just have more children but also produce children who were less able than their brighter counterparts.

In the US the Immigration Act of 1924 placed restrictions on the numbers of immigrants from certain countries, whom eugenecists at the time believed would contaminate the population as a whole due to their overbreeding and low intelligence.

This would now appear to be a crude untruth. The Norwegian study mentioned above had access to the IQ scores of some of the parents and their children and it found that even when bright parents were identified the scores in their children were lower.

Moreover they, and not the less intelligent, had larger families, thus discrediting the belief that the fecundity of low IQ parents was responsible for the decline in measured intelligence overall. Most people who have studied this believe that it is environmental factors that are at play rather than genes.

These include the education system, nutrition, the increasing use of the internet, reading less and the focus on social media rather than on face-to-face conversation stimulating critical thinking.

At this stage, the exact factors from this list are speculative and more research is required to elucidate them with greater specificity.

It is also possible that improvements in public health such as sanitation and nutrition along with more stimulating environments have gone as far as they can in aiding our intelligence, at least in the developed world.

Intelligence, and the factors that influence it, is something that commentators are loath to discuss because of the eugenic connotations.

Yet if the decline in intelligence in the population at large continues the implications are serious. It has implications for political debate, personal aspirations and the education system. It cannot be ignored.

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