This article was originally published on The Conversation.
We’re getting more stupid. That’s one point made in a recent article in the New Scientist, reporting on a gradual decline in IQs in developed countries such as the UK, Australia and the Netherlands. Such research feeds into a long-held fascination with testing human intelligence. Yet such debates are too focused on IQ as a lifelong trait that can’t be changed. Other research is beginning to show the opposite.
The concept of testing intelligence was first successfully devised by French psychologists in the early 1900s to help describe differences in how well and quickly children learn at school. But it is now frequently used to explain that difference – that we all have a fixed and inherent level of intelligence that limits how fast we can learn.
Defined loosely, intelligence refers to our ability to learn quickly and adapt to new situations. IQ tests measure our vocabulary, our ability to problem-solve, reason logically and so on.
But what many people fail to understand is that if IQ tests measured only our skills at these particular tasks, no one would be interested in our score. The score is interesting only because it is thought to be fixed for life.
A version of this article originally appeared at The Conversation.
There could be a way of predicting – and preventing – which children will go on to have low intelligence, according to the findings of a study researchers at Cardiff University presented on Monday. They discovered that children with two copies of a common gene (Thr92Ala), together with low levels of thyroid hormone are four times more likely to have a low IQ. This combination occurs in about 4% of the UK population.
Importantly, if you had just one of these factors, but not both, there did not appear to be an increased risk of low intelligence. These are early results, but suggest that it might be possible to treat children early with thyroid hormone supplementation to enhance their intelligence. This raises many ethical issues.
A common objection is that being smarter does not make your life better. In this study, researchers were concerned with those with an IQ between 70-85. Below 70 is classified as intellectual disability but an IQ of 70 to 75 is similar to mild intellectual disability.
Even for individuals with an IQ between 75 and 90 there are still significant disadvantages. Job opportunities tend to be the least desirable and least financially rewarding, requiring significant oversight. More than half the people with this IQ level fail to reach the minimum recruitment standards for the US military. Individuals with this lower level of intelligence are at significant risk of living in poverty (16%), being a chronic welfare dependent (17%) and dropping out of school (35%) compared to individuals with average intelligence. Studies show that they also face an increased risk of incarceration and being murdered.
Linda Gottfredson, who’s undertaken much of this research, concludes that at the very least, “an IQ of 75 is perhaps the most important threshold in modern life”. So it is clear that those of low-normal intelligence, although not classified as disabled, are significantly disadvantaged.
If we could enhance their intelligence, say with thyroid hormone supplementation, we should.
Dan Hurley is writing a book about new research into how people can increase their intelligence. His latest article for DISCOVER, published in April, was about how the brain forms memories.
Can you consciously increase your intelligence? That question was the title of an article I wrote in April for the New York Times Magazine, examining studies showing that people who train their working memory with specially designed games show increases in their fluid intelligence, the ability to solve novel problems and identify patterns. In particular, the article focused on a game called the N-back task, in which a participant is challenged to keep track of spoken words or locations on a grid as they continuously pile up.
While some skeptics doubt that anything as profound as intelligence can be increased in as little as a month by playing a silly game, far stranger methods are also being tested. And the results keep getting published in respectable journals, showing significant effects.
Perhaps the most seemingly absurd approach is the use of “first-person shooter” video games, like Call of Duty. Studies by Daphne Bavelier at the University of Rochester have found that practicing the games improved performance on an array of untrained sensory, perceptual, and attentional tasks. Notably, the transfer is broad enough to improve trainees’ ability to distinguish an auditory signal from white noise, despite the fact that no auditory training was involved in the games, and that two distinct brain areas are involved in auditory and visual processing.
“This is not the first kind of activity you’d think is good for the mind,” Bavelier told me. “But there is a whole field of research showing that executive control and the ability to decide whether to attend to something or not is a main determinant of intelligence. In that sense the games are making you smarter. Whether they will make you do better on an exam, I cannot say.”