1 February 2013. Political scientist James R. Flynn first discovered from careful statistical analyses of IQ results from many countries that the IQ increased with time. It was happening at a rate of three IQ points every decade for as far back as the tests had been conducted. It was later dubbed the Flynn effect.
The obvious conclusion seemed to be that, for some reason, people were getting smarter. Flynn summarized his experience some years ago in “What Is Intelligence?”, but in a new book published last year, Flynn asks “Are we getting smarter?”
In his new book, Flynn clarifies that there is a difference between intelligence and an IQ score. So the rising IQs may be a reflection of the world in which we live, the educational system, media, communications and all. It may be that the brain as such is not getting any better, but more that it is being exercised more and, just like a muscle, getting better at doing the job. Thus, IQ tests are regularly updated with new norms, so that the average remains close to 100. As an example, one of the early IQ tests included a map sketch of the US with Florida chopped off. The subject was then asked what was missing from the drawing. That question became way too easy, once everybody got a TV and saw the weather map every evening.
As a political scientist, Flynn does not dwell at the variety of brain functions and domains that occupy psychologists a great deal. A high IQ is known to be related to academic success and high income, so the IQ counts, even if it is a non-specific omnibus measure. Some of the known gap between developing and industrialized countries may well relate to differences in schooling and culture. This gap between north and south remains, although we may all be getting better at graduating and at landing a well-paid job.
But within populations and between countries, can we attribute the time trends to the fact that we are using our brains more efficiently? This is quite likely part of the explanation. But many other factors may play a role, too. Maternal nutrition during pregnancy, parasite infestation, domestic violence, and many other adverse influences can halt a child’s brain development, and removing such risk factors can make the IQ results increase.
And then there are the chemical brain drainers. Studies in New York City have shown how SAT scores improved with a 17-year delay after the phase-out of lead additives in gasoline began. Thus, some IQ improvement gains may be due to better control with some known chemical brain drainers. A recent article calculated that, if mercury exposures from seafood are curbed, then EU newborns will gain about 600.000 IQ points every year. That is no small gain, and economists have calculated that it corresponds to €8-9 billion annually based on prospective life-time incomes.
Will Flynn’s rising trend continue? Hopefully so. But that is no reason to consume the gain by allowing some more chemical brain drain. That would be like driving faster, because you have air-bags in the car. Exposures to pesticides and other brain-toxic chemicals can wipe out the gain and possibly even cause a reversal of the Flynn effect. Even if we appear to be smarter, that would be really dumb.