Flynn effect: are we getting smarter?

At the end of the 20th century, a worldwide trend of increasing scores on intelligence quotient (IQ) tests was detected when comparing successive generations. This phenomenon is known as the Flynn effect. and it is especially important in populations of low socioeconomic status.

However, increases in IQ due to the Flynn effect have recently been reduced in rich countries, to the point of that other factors have overtaken it, making the current trend in these places towards declining intelligence half.

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What is the Flynn effect?

The researcher James Robert Flynn (1934-) has defended during his professional career the fact that intelligence depends largely on environmental factors, which make it unnecessary to resort to intergroup explanations, such as the genetic superiority of certain social groups.

The term “Flynn effect” was coined by Richard Hernstein and Charles Murray in the book The Bell Curve (1994). These authors used it to describe the

increase in IQ that occurs with generational changes, a phenomenon that has been detected in many parts of the world and that Flynn helped spread.

The Flynn effect occurs in the fluid intelligence, crystallized, spatial, and global IQ, but is particularly noticeable in fluid IQ scores. In contrast to crystallized intelligence, which depends on experience, fluid intelligence is defined as the ability to solve new problems and is attributed mainly to biological factors.

Various studies and meta-analyses carried out worldwide have confirmed the cross-cultural nature of the Flynn effect. However, it seems to occur almost exclusively in populations of low socioeconomic status, which most likely indicates that it is related to environmental factors.

Likewise, the magnitude of the Flynn effect has decreased over time, at least in rich countries. Added to this are other phenomena that influence what is currently the global trend has reversed and is now negative; we will talk about this later.

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Explanations of this phenomenon

Since the increases in intelligence that have been detected have occurred too rapidly (sometimes as much as 10 IQ points in 30 years) to be due to genetic variation, proposed explanations for the Flynn effect focus primarily on the environment.

1. Improved schooling

Some authors have proposed that the Flynn effect is simply due to increased literacy rates, which are associated with improved IQ. On the other hand, access to high-quality schooling, especially in children of low socioeconomic status, could also explain part of this phenomenon.

2. Compensation of nutritional deficits

nutritional deficits interfere with physical development of children, and therefore also in the cognitive. In places where infant feeding is not adequate, as was the case in most of the world a century ago or in many African countries today, IQ scores are generally higher low.

It is important to bear in mind that these effects overlap with educational improvements after a certain age. In any case, it is believed that nutrition may be more relevant to intellectual development very early in life.

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3. Advances in medicine

Like the improvement in nutritional conditions, medical progress has allowed the healthy development of many people. According to some studies, it is particularly important reduction in the number of infectious diseases, as well as in its severity; This type of alteration can affect the brain if not treated properly.

4. environment enrichment

Flynn himself defended in his book "What is intelligence?" (2007) that recent changes in society have increased the abstract reasoning capacity of the world population. These variations can be technological or social, mainly.

Among the relevant factors Flynn highlights familiarization with new technologies, which can be stimulating for the brain, the increase in academic and work demands and the decrease in the number of children per family, which would allow an improvement in the attention and care received by the little ones.

5. Familiarity with IQ tests

In addition to the popularization of IQ tests, this factor is related to the increase in literacy rates and the improvement of formal education. Schooling enhances the capacity for abstract thought and therefore allows higher scores to be obtained in the instruments that measure intelligence.

In the same sense, the test format has been extended significantly during the last decades as form of educational testing, including tests with verbal and mathematical items very similar to some tests of IC. This may also have influenced the familiarity with this type of evidence.

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Are we getting smarter?

Although the Flynn effect remains significant at low socioeconomic levels and in poor countries, Studies carried out in recent decades confirm that the influence of this phenomenon is being reduced at the world. This means that currently the average IQ level tends to go down, even maintaining the Flynn effect.

According to various investigations, the Flynn effect has been overcome by other factors that favor a reduction in the average IQ in countries such as the United Kingdom, Norway, Denmark or Australia. Experts also predict that this decline will continue for at least the rest of the 21st century in Europe and the United States, if the current trend continues.

However, it is anticipated that the increase in intelligence will continue to occur in regions where the needs of the population are covered to a lesser extent, as is the case in Latin America, East Asia, the Arab countries, Africa and the India.

At the moment, the exact causes of this phenomenon have not been determined. There are those who relate it to the arrival of immigrants from countries with a lower average IQ, but the research does not support this hypothesis. Historically, the decline in intelligence has been attributed to the fact that people with a higher IQ tend to have fewer children.