Reverse Flynn Effect: After Decades of Increasing IQ, Are Humans Getting Dull-witted?

For decades, IQ scores have been rising, but the trend has now reversed. This phenomenon is called the reverse Flynn Effect.

What Is the Reverse Flynn Effect?

In the early days of the 19th century, scientists were under the impression that one could possibly get a lead on underlying intelligence based on observations of practical, definite abilities, among them verbal reasoning and working memory. Psychologists Alfred Binet and Theodore Simon began working on a kind of test to measure such skills and others like visual-spatial, which became the precursor for the IQ test.

Created in 1905, IQ tests were basically developed to find out which children needed extra attention in schools. Through the years, IQ tests were used to analyze different cognitive skills and potentials possessed by a person.

The Flynn Effect got its name from the contention that IQ scores change over time and, more specifically, show an apparent increase in intelligence by the general population through a steady increase in variables. This phenomenon was first described by intelligence researcher James Flynn.

In 1984, Flynn discovered that from 1932 to 1978, there was an increase of 13.8-point IQ score. This substantially translates to an approximate 3-point per decade increase in IQs. The phenomenon determined that with time, people's average IQ increases and showed promise that the intelligence of our society only increases with the development of civilizations.

Experts, however, found a newer phenomenon in recent years, marked by a decline in intelligence. They found that children born in 1975 reached 'peak IQ,' and average intelligence had been dropping ever since.

In the paper "Looking for Flynn effects in a recent online U.S. adult sample: Examining shifts within the SAPA Project," researchers concluded that American IQs are falling for the first time ever. Led by Elizabeth M. Dworak, the researchers analyzed shifts in 394,378 scores on intelligence tests completed from 2006-2018.

It was found that IQs had dropped in all other areas except spatial reasoning. Scores significantly dropped in visual problem-solving and analogies, computation and mathematics, logic, and vocabulary.

What Causes the Decline in Intelligence?

The general decline in intelligence is however not a declaration that our society is getting less intelligent. It is more of an implication of a changing society.

This decline is then attributed by studies to changes in reduced nutrition, quality of education received, and test-taking behavior. It is hypothesized that younger generations are experiencing decreased test-taking confidence or are not responding particularly well to the format of IQ tests.

Meanwhile, some experts argue that average IQs decline due to dysgenic fertility- the less intelligent have more children than the smart folk.

On the other hand, another study in 2018 found that IQ scores fell off even within families and not just across society. That fits data showing the children and grandchildren of high-IQ American immigrants see their scores regress toward the national mean.

Human intelligence is way too complex to be captured with a standardized test. The media, cultures, and even our environment are continuously changing and evolving.