Are People Becoming More Intelligent: A Discussion in Relation to the Flynn Effect

In 1981 James R Flynn began a process of examining intelligent quotient tests and found, that between the years of 1932 and 1978 in America, the mean intelligent quotient (IQ) test scores rose by 13.8 points, which equated to 0.33 points per year (Flynn, 1984). Other researchers found this increase in IQ scores continued on into the mid 1990s (Rowe & Rodgers, 2002). Additionally, this rise in the scores was not confined to the United States alone, with Flynn, (1999) reporting a 27 point gain between 1942 to 1992 in the UK and Flynn, (1987) reporting smaller increases in other countries such as Norway, France and Holland. Additionally, the increases in IQ points has not been confined to developed countries with Daley, Whaley, Sigman, Espinosa, & Neumann, (2003) reporting increases in developing countries over a 14 year period. This year on year increase in IQ scores has now become known as the Flynn effect. But does this mean that generations are gradually becoming more intelligent? This paper will discuss this question by examining the Flynn effect and possible explanations to this phenomenon.

As part of the process of validating and establishing norms for new IQ tests, groups of participants are required to take the old and new versions of IQ tests to ensure the results of the two tests correlate. In 1981 James R Flynn began a process of examining the results from the older and newer versions of these tests and noticed that there was a significant gain in IQ points between the population that took the test originally and the population that took the same test when helping to establish the norms for the revised versions of the tests (Maltby & Macaskill, 2010). This led Flynn to widen his research and examine 73 other American studies and later to investigate 14 other countries, and concluded that there was a year on year rise of IQ test scores across nations and cultures, albeit smaller increases were noticed in some countries e.g. Norway, France and Holland (Flynn, 1987). These findings were subsequently backed up by various other studies (e.g. O. Must, te Nijenhuis, A. Must, & van Vianen, 2008; Daley et al., 2003)

Although there is a noticeable year on year rise in intelligence test results Flynn does not believe that generations are actually getting more intelligent. If this were to be the case, based on his figures, Flynn suggests there would be 20 times more geniuses alive (Maltby & Macaskill, 2010). Though, how are geniuses identified and recognised in order to be able to quantify them? A genius is one who is highly creative, inventive and productive, and not merely someone who scores high on conventional IQ tests (Albert, 1975). Feldman, (1984) concurs with Albert (1975) after examining the lives’ and achievements’ of 26 individuals with IQ scores above 180 and found that an extremely high IQ does not seem to indicate that the individuals will be any more creative or inventive than the average population. No matter the definition, it is difficult to identify, and therefore quantify, geniuses as they could be quietly being creative in their own lives and not yet come to be known to the general population.

There are, however, a number of researchers who do not agree with Flynn and suggest that generations are actually getting more intelligent. Comparing the cognitive development of children who were the same age, from studies carried out in 1967, 1972, 1993 and 1996 A Flieller, (1999) found that children in the 1990s showed an improved level of cognitive development than similar aged children in the 1960s and 1970s studies. Furthermore, Bocerean, Fischer, & Andre Flieller, (2003) found that children in 2001 showed improved mathematical ability than did similar aged children in 1921.

So if Flynn does not believe generations ...

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So if Flynn does not believe generations are getting more intelligent then how is this year on year increase in IQ test scores explained? Flynn believes that IQ tests do not measure intelligence but actually they correlate with intelligence, and it is not intelligence that is improving from one generation to the next but some kind of improved problem solving ability (Maltby & Macaskill, 2010). This could call into question the validity of intelligence tests and their purpose, if in fact they are not actually giving a measurement of intelligence. So whether it is intelligence that is increasing or a problem solving ability that is being honed, there is still the evidence that the IQ scores are increasing across generations, which still requires explanation.

Flynn does not believe that there can be any weight given to a genetic explanation to the rise in IQ scores because the timescales within his study periods were too short to allow for genetic change, and he favours a more nutritional hypothesis and other socio-economic status (SES) correlatives (Maltby & Macaskill, 2010). Capron & Duyme, (1989) concur with this SES hypothesis to explain the rise in IQ scores when they performed a cross fostering study looking at children born into high and low SES families and children adopted into high and low SES families when having the opposite SES biological families. They found that children adopted by high SES parents scored higher than children adopted by low SES parents and children born to high SES parents scored higher than children born to low SES parents. They also found there was no evidence for an interaction between the SES the child was born into and that which they were adopted into. This study by Capron & Duyme, (1989), and others like it, might also help discredit the assortive mating theory towards the increase in the rise in IQ scores, and therefore add more weight to Flynn’s arguments to discount a genetic explanation.

There are, however, researchers who suggest there are genetic links to intelligence (Kanazawa & Kovar, 2004) and with more people travelling and marrying outside their local groups, populations could have benefited from outbreeding vigour. There are some researchers that suggest that this heritability of intelligence i.e. the percentage of its variation that can be attributed to its variation in genes, steadily increases with age (McCartney, Harris, & Bernieri, 1990). Finkel, Pedersen, McGue, & McClearn, (1995) even suggests that heritability of intelligence appears to be distributed over a bell curve where the heritability in preschoolers is less than 3%, 81% from ages of 27 to 65 years and drops to 54% between the ages of 65 to 85 years. A possible explanation for this could be that that heritability for intelligence exists, but this is only amplified with prolonged environmental stimulation, and aging differences could account for the decline from 65 years of age onwards.

One of the explanations that Flynn does suggest for the rise in IQ scores is that populations are becoming increasingly adept at taking intelligence tests (Flynn, 1984). One reason why this theory might be discounted is that there is evidence to suggest that the Flynn effect is slowing down or actually in reversal (Sundet, Barlaug, & Torjussen, 2004). Sundet et al., (2004) tested the IQ of Norwegian male conscripts from the mid 1950s to 2002 and found that up until the 1980s the conscripts increase in height correlated with their IQ scores which implied there was a nutritional link to IQ scores. However, in the 1990s there was a decline in the rise in the IQ scores noticed and the eventual halt in the rise in IQ scores was recorded. Although this study does loosely control for SES by correlating heights, what this paper fails to take into consideration is the family size and structure the conscripts came from. There are a number of researchers who believe that the smaller the sibling group the higher the individuals IQ will be (Sundet, Eriksen, Borren, & Tambs, 2009). Whilst there are others that believe that it is the birth order that is important (Black, Devereux, & Salvanes, 2004).

Another reason to discount Flynn's, (1984) suggestion that individuals are becoming more practised at test taking is that it should be expected that there should be an increase in scores across all tests or exams. However, during the same period that American IQ scores were increasing the American SAT scores decreased (Zajonc & Bargh, 1980). Although Flynn, (1984) suggests that SAT and IQ scores are highly correlated, Chall, (1996) posits the decrease in SAT results could be down to teaching practises, which would not affect general intelligence. Interestingly, as previously discussed Sundet et al., (2009) reflected an increase in IQ points with a smaller family size whereas Zajonc & Bargh, (1980) suggest there is no significant link between SAT score decline and family configuration. So perhaps there is less of a correlation between IQ and SAT score than Flynn, (1984) posited.

This essay has discussed whether it is possible that generations could be becoming more intelligent by defining the Flynn effect and exploring what the Flynn effect is measuring. This paper also provides a critical evaluation into the explanations that Flynn has provided to explain the year on year increases in IQ scores. Although the debate on the Flynn effect continues, the importance of this research is paramount as the investigation into the Flynn effect may help establish what IQ tests are really a measure of and whether intelligence should be labelled based on IQ tests. Additionally, if the Flynn effect is found as being significant, then society has a moral obligation to consider adjusting for the Flynn effect when it comes to major decision making such as assessing mentally disabled.

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