If you feel that the world is becoming less intelligent in some way, the data from Norway, Denmark, Finland, France, Britain, and Australia agrees with you, with average IQ scores in those countries f

Key Points:

• The Flynn Effect, observed from the 1930s to the 1990s, showed a consistent rise in average IQ scores of about three points per decade in industrialised countries, attributed to increased cultural exposure to abstract reasoning rather than biological changes.
• Since the mid-1990s, this trend has reversed, with documented IQ declines in countries including Norway, Denmark, Finland, France, the Netherlands, Britain, Estonia, Australia, and the United States, confirmed by longitudinal family data indicating environmental causes.
• Various hypotheses for the reversal are under investigation, including changes in education methods, increased screen time, environmental factors like nutrition and pollution, and the possibility that modern IQ tests no longer align well with contemporary cognitive skills.
• The reversal does not imply a biological decline in intelligence or overall cognitive capacity but suggests a shift in the types of cognitive abilities practiced and developed, highlighted by improvements in 3D spatial reasoning linked to digital environments.
• The continued decline poses significant questions about the future cognitive skills underpinning critical societal functions, and researchers have yet to determine what factors could halt or reverse this trend.