The Flynn Effect: A Historical Perspective

The Flynn effect, named after James R. Flynn, refers to the observed trend of rising IQ scores from 1938 to 1979. This increase was substantial, with IQs rising between 5 and 25 points on standardized tests. The IQ scale is somewhat peculiar, with the average score set at 100. Therefore, a score above this average indicates above-average intelligence. Mensa, the organization dedicated to identifying and nurturing human intelligence, accepts only the top 2% of test-takers, which translates to a score of 132 or higher on the Stanford-Binet test. The additional 25 points that Flynn noted could potentially elevate an average individual today into Mensa territory—if only it were that simple.

James R. Flynn himself was a fascinating figure. Hailing from a Catholic Irish-American background, he abandoned Catholicism by the age of 12, favoring scientific inquiry over creationist teachings. Over his lifetime, he contributed significantly to various fields, including research on IQ, equality, and climate change, championed racial equality, emigrated to New Zealand, and even ran for parliamentary office there.

The Reversal of the Flynn Effect

If we accept the Flynn effect as valid, what then is the issue? Are we not becoming smarter? The complication emerges when examining data collected after the initial findings, particularly from the 1970s onward, where the Flynn effect no longer appeared. Instead, evidence suggested that average IQ scores were declining—essentially, we are becoming less intelligent.

However, a closer inspection of the data reveals that the IQ gains observed by Flynn primarily arose from those at the lower end of the scoring spectrum. In essence, those who previously performed poorly on IQ tests were improving over generations, thus raising the average, while the higher-scoring individuals showed minimal improvement. Factors such as prenatal and postnatal nutrition, exposure to intellectual stimuli during early childhood, and wider access to education likely contributed to the initial rise in IQ scores. It seems that environmental elements were responsible for the improvement rather than genetic factors; our potential for intelligence remained stable, but our ability to express that potential improved.

Examining Environmental Influences

So, if environmental factors led to improved IQ scores, could they also be responsible for this decline? Since the 1970s, we have entered the technological age, where we delegate most cognitive tasks to computers, a significant shift to consider. My mother’s warning still echoes in my mind: “Get off that computer or it will rot your brain.” While technology is a major factor, it is not the sole change; our diets have also evolved dramatically due to industrialized agriculture, pesticide use, and the rise of processed foods. Urbanization has transformed our living environments, increasing our exposure to various chemicals as well.

This situation exemplifies correlation without causation—many factors changed concurrently with the decline in IQ scores, but that does not imply they caused the decline.

In terms of chemical changes in our surroundings, the use of flame retardants has become widespread since the 1970s, intended to provide extra time for occupants in case of a fire. While this seems like a commendable use of technology, research indicates a connection between certain flame retardants, known as PBDEs (polybrominated diphenyl ethers), and reduced IQ in children. These chemicals are prevalent in furniture, electronics, carpets, and various consumer products, affecting the endocrine system and potentially causing neurodevelopmental delays in young children.

Debating Intelligence Trends

Experts have yet to reach a consensus on whether intelligence is genuinely declining. Scholarly discussions revolve around whether shifts in score collection methods, the validity of IQ tests as measures of intelligence, and other statistical intricacies complicate the understanding of cause and effect. Conversely, it is possible that the reversal of the Flynn effect is indeed genuine and environmentally induced. While scientists work to decipher this complex puzzle, I will aim to limit my family’s exposure to chemicals and prioritize whole foods. As for my mother’s warnings about technology, those will need to take a back seat for now, as my screen time continues to soar!