Adults can concentrate better and better
According to intelligence tests, the average IQ has been rising for decades. This "Flynn effect" can also be seen in a standard attention test - but only in adults. The situation is somewhat different for children.
The ability of adults to concentrate has increased over the past 20 to 30 years. This is the conclusion of a meta-analysis published in the journal "Personality and Individual Differences". The research group led by Denise Andrzejewski from the University of Vienna sees this as initial evidence that attention is also subject to the Flynn effect.
The Flynn effect refers to a phenomenon that was observed in many countries in the mid to late 20th century: The mean intelligence quotient - the result of standardised intelligence tests - increased from generation to generation. The effect is named after the political scientist James Flynn, who first reported on it in 1984. On average, IQ has increased by around three points per decade, but the trend has since stagnated in some countries, and in some the trend has even reversed. Experts still do not agree on the causes.
The ability to concentrate could be a building block of general intelligence and one of the causes of the Flynn effect. With this idea in mind, the team led by the Viennese psychologist analysed data from 179 studies involving a total of more than 21,000 people from 32 countries, including Germany, Austria and Switzerland: between 1990 and 2021, they all had the standard psychological test "d2", which measures the ability for selective and sustained attention - the ability to concentrate.
The test consists of 14 lines (12 lines in the new version), and each line is filled with 47 characters, including only the letters d and p and sometimes one or two small vertical lines above or below the letters. The task: to cross out each d with two strokes, as error-free as possible, but also as quickly as possible, as the time is limited to an average of 20 seconds per line.
On average, the concentration performance (defined as the number of correct minus incorrect answers) of the adults increased moderately over the years. However, it remained roughly the same for the children: although they worked increasingly faster, they made more mistakes. The researchers interpret this as an indication of impulsive, more superficial test behaviour, possibly caused by the fact that society today is more error-tolerant and that performance is measured by speed rather than accuracy.
However, the results were somewhat different when the group looked at the German-speaking countries separately. The children did not make more mistakes here, but fewer, and the adults' ability to concentrate did not increase. Nevertheless, the overall conclusion across more than 30 countries was that the Flynn effect also applies to the ability to concentrate. And this increase could contribute to an increase in intelligence - the actual Flynn effect.
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