Under the Microscope Prof William RevilleAn American professor of philosophy, James Flynn, made the remarkable discovery in 1984 that average intelligence quotient (IQ) scores for all industrialised countries had been steadily increasing for the past 60 years.
Many researchers have since confirmed this phenomenon, which has come to be called the Flynn Effect. There is no consensus yet as to why this occurs, but Flynn has proposed a reasonable explanation.
Companies that produce IQ tests generate new tests approximately every 10 years, and each new test is normalised by administering it to a large representative sample of the population. The quality of the responses distribute themselves on a bell-shaped curve when displayed on a graph. The average score, at the top of the bell, is assigned a value of 100. To make sure that new tests synchronise with older tests, batches of participants take both tests. In the early 1980s, Flynn studied this data and noted: "Every time the kids took the new and the old tests, they did better on the old ones." He went on to study the effect in detail, and since then many others have confirmed it.
A consensus based on extensive research has grown in recent decades to the effect that IQ is a largely inherited trait. The heritability of IQ is generally reckoned to be about 60 per cent, leaving 40 per cent to be accounted for by the environment. But heritability cannot reasonably account for the Flynn Effect - the increase in IQ is too large and has happened too quickly. We simply cannot be evolving that fast. Why then are IQ scores getting higher? Environmental factors must play an important role. Several explanations have been suggested, including better education, improved nutrition, a trend towards smaller families, and greater environmental complexity.
The rise in IQ test scores occurred at greatly varying rates in different parts of the world, but the average rate of increase is about three IQ points per decade. Children attend school much longer now than in the past, and therefore it would be expected they would do better on school-content-related tests of vocabulary, arithmetic or general information. But such abilities have shown very small improvements over the years. The largest Flynn effect is seen with culturally neutral tests such as Raven's Progressive Matrices, which minimise the need for specific skills or familiarity with words and symbols.
Improved nutrition might play a small part in the Flynn Effect, but it must be remembered that poor diet hasn't really been an issue in the West since the early 1950s.
The general environment today is much more complex and stimulating than in the past and there has been a huge increase in exposure to many types of visual media such as TVs, video games and computers. Each successive generation is exposed to richer optical displays, possibly making people more adept at visual analysis. This might explain why tests such as Raven's have shown the greatest increases, since they depend on such analysis.
Flynn proposes that the heritability of IQ includes both a direct effect of the genes on IQ and an indirect effect, whereby the genes change the environment, in turn affecting IQ. In other words, those with a naturally higher IQ tend to seek out environments that are stimulating and those environments further increase IQ. The direct genetic effect on IQ could be small, but the indirect feedback loops might create large differences in IQ.
So, the environment can affect heritable traits such as IQ, but what part of the environment is making us smarter? Flynn points the finger at "cognitively demanding leisure". The Flynn Effect is most pronounced on tests such as Raven's, which presents you with a series of visual grids, each composed of a mix of shapes that seem vaguely related to one another. One shape is missing from each grid and you must choose the correct missing shape from eight possibilities. To solve this puzzle you must analyse a changing set of icons, looking for unusual patterns or correlations among them. This is not the kind of thinking you get practice at by reading a book or holding a conversation. But it is exactly the type of thinking you do when learning how to master your new mobile phone, your new DVD player or your new TV remote. Over the last 50 years, we have had an explosion of new technologies, and our interaction with them forces us to grapple with the logic of the new interfaces, to sense relationships and to follow clues - the same skills measured by the Raven's test.
Whatever about evidence for a general increase in IQ, I am aware of no evidence for any increase in wisdom. Wisdom can be thought of as accumulated knowledge combined with good judgement and insight into inner qualities. It can be defined, in a practical sense, as the ability to foresee consequences and acting to maximise the long-term good. Most psychologists regard wisdom as distinct from the cognitive abilities measured by intelligence tests. It is a trait that can be developed by experience, but not taught.
Intelligence has to do with our abilities to process data. Wisdom is concerned with what to do with the results produced by intelligence. As Plato said: "Wise men talk because they have something to say; fools because they have to say something."
William Reville is Associate Professor of Biochemistry and Public Awareness of Science Officer at UCC - understandingscience.ucc.ie