Ausgabe 36/2010

How Hereditary Can Intelligence Be? Studies Show Nurture at Least as Important as Nature


Part 2: IQ Increases with Each Year Spent in School

By contrast, IQ increases with every year a child spends at school. During World War II, some children in Holland started school late because of the Nazi occupation -- with momentous consequences. "The average IQ for these children was seven points lower than for children who came of school age after the siege," Nisbett says.

Unequal educational opportunities were and still remain particularly prevalent in the United States. American society denied black slaves an education, and refused them access to books. But the races remained divided even after the abolition of slavery in 1865. For a long time, dark-skinned children attended special schools that had terrible facilities. So it's hardly surprising that they were behind when they were finally granted access to the public schools that were previously the sole preserve of white children.

White academics in the US repeatedly tried to claim that the resulting differences in performance were genetically determined. In the 1960s, psychologist Arthur Jensen from the University of California at Berkeley wondered why so many underachieving pupils were dark-skinned. How could anyone deny that their low intelligence was a feature of their ethnicity, Jensen argued. He therefore concluded that there was no point in trying to encourage children from socially disadvantaged groups at an early age.

The controversial book "The Bell Curve" was published in 1994. Its authors, Richard Herrnstein and Charles Murray, warned against giving ethnic minorities easier access to universities.

An Unplanned Experiment in Germany

This is the line of reasoning that German central banker Thilo Sarrazin recently adopted when he provocatively suggested that the children of Turkish immigrants were genetically less well disposed than German children.

In spite of Sarrazin's claims, an unplanned experiment that took place in Germany proved long ago that skin color had no influence on intelligence. After World War II, many American servicemen fathered children with German women. These bi-national offspring were dubbed "occupation babies". Some of them had light-skinned American dads, others dark-skinned ones. In contrast to the US, this had no influence over their performance at school.

In 1961 Klaus Eyferth at the Hamburg University Institute of Psychology saw this as a unique opportunity to uncover the "developmental characteristics of (biracial) children" by comparing them with "white occupation babies." Eyferth gave intelligence tests to 264 children and adolescents, 181 of them with dark skin, 83 with light skin. The children with a white father had an average IQ of 97, those with a black father 96.5, values statistically so close to one another to disprove the notion of "developmental characteristics."

Hundreds of Thousands of Genes Play Role in Cognitive Skills

Modern genetic research has also now shown that there is no such thing as a biological source of cleverness consisting of one or a few "intelligence genes." Apparently there are hundreds -- if not thousands -- of genes that play a role in determining our cognitive skills.

A person's ability to make use of his or her genetic potential can indeed be influenced, especially if the person is assisted and permits others to help. Education researcher Anders Ericsson has also shown that master musicians, for example, aren't born that way. Studying violinists in Berlin he found that none who had practiced for fewer than 10,000 hours ever became virtuosi. By contrast, nearly all those who had practiced for more than 10,000 hours by the age of 20 went on to become principal violinists.

The analogy doesn't only hold for musicians. The notions of "chess genius" or "math genius" are likewise mere metaphors that don't have any biological basis whatsoever.

True, time and again it has been observed that children in several Asian countries are far better at calculating than their peers in the West. But that has nothing to do with genetics -- and everything to do with attitudes. In one study, students from Japan and Canada were given mathematical tasks. No matter how well they actually did, the researchers told one group of subjects they had done excellently. The others were informed they had flunked completely. The scientists then gave the subjects another set of tasks, and said they could take as long as they wanted.

The reactions by the students showed remarkable cultural differences. The Canadians were apparently motivated by success. Those who had been told they had done well in the first test spent significantly longer doing the second task than fellow Canadians who were given to believe they had done terribly the first time round. The Japanese subjects behaved quite differently. Those who had been given a bad grade in the first test worked longer and more diligently than those who had been praised. It therefore seems that a sense of failure was motivating for them.

Cognitive Skills a Reflection of Environment

Numbers aren't the only thing you can teach through repeated practice. The same is true for words. A person's vocabulary is an expression of how much their parents and significant others spoke to them as a child. According to studies conducted in the US, the average child has heard about 30 million words by the age of three. The figure for disadvantaged children is only 20 million. This then affects their active vocabulary. The average middle-class three-year-old can use 1,100 words, whereas children from poorer families only have about 525 at their disposal.

The new findings by the intelligence researchers all point in the same direction: Our cognitive skills are a reflection of our environment. "The low IQs expected for children born to lower-class parents can be greatly increased if their environment is sufficiently rich cognitively," says psychologist Nisbett.

The practical possibilities have been explored by psychologists Sharon Landesman Ramey and Craig Ramey from Georgetown University in Washington, DC. The Rameys used as their subjects the children of extremely poor and poorly educated parents. In one project children spent their days at a special day-care center in which there was one teacher for each child and where the young charges were given special encouragement from the age of six weeks.

After three years, these children were compared to a control group. Lo and behold, the average IQ of the boys and girls was a staggering 13 points higher than that of similar children who had not been given special attention.

Translated from the German by Jan Liebelt


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Norberto_Tyr 09/13/2010
1. Thinking is like digesting, a bodily function, as Schopenhauer would say
Thinking, the main operation of the brain, is like digestion to the stomach, merely a bodily function; then I do not know how the ability to think according to a-priori patterns imprinted in our brain operating under the forms of time and space could not be inherited as any other physical trait. On the other hand, the question about intelligence taxonomy, namely how this ability is distributed within the human kind is a completely different subject matter, let alone the definition of ‘intelligence’. When an organized group of people attempts to take possession of the ‘intelligence’ definition in order to pump-up their rather floppy self-esteem we are up for mischief on a grand scale. Regardless of the rather diffuse definition of ‘intelligence’ suffering from well known limitations, the empowering industry of intelligence tests (imagine that you are able to classify people like in the Guinness books of records) allows a Babieca becoming a demigod generating million of US dollars (for what they worth since these ‘assets’ are someone’s else liabilities) through books, lectures, reputation and entertainment. This is the proof of a theory I proposed long ago, namely that the professions we choose are compensation for our own perceived defects, for example, a person wishing to measure people’s intelligence betrays his doubts on his own intelligence. By placing himself above the rest he avoids been tested himself, thus, a judge might be someone that thought of himself a liar when he was a kid, a journalist, someone that is trying to hide a personal secret so he fends himself discovering others, in the same way that ‘Become a millionaire in one week’ can only be written by someone doubting that that is possible, otherwise he would not have wasted weeks writing it. I see Sarrazin labeling people at willy-nilly within this context, I do see Wilders in the very same business as well. They doubt their own skills and talent therefore they believe that projecting their own inferiority complex to others are protecting themselves. This is a serious problem, as demonstrated by history, even though they cannot fool themselves they might be able to fool others, and that is dangerous. For instance, in the recent past someone was caught unexpectedly in an incredibly precarious situation as it was, apparently, incredibly successful, the problem was that all his victims mistakenly believed that he was the source of the success, and of course, he could not disappoint them. Now, a sensible person would have had taken advantage of the situation by loosing prestige but saving the day, but not, prestige was his only asset so he doubled the bet over and over again until it was utterly unsustainable, then he laconically said: ‘ok, I quit’, so he would not witness people witnessing that the king was naked. This proves another theory, a disability can become an asset, and vice versa. For example, a group of people lacking talent might protect themselves combining and supporting each other regardless. Kissinger I believe once said: ‘successful defensive strategies gradually shift to the offensive’. Yes, a real or perceived threat can trigger this behavior. We must not dismiss the fact that the disappearance of the threat would deflate the power of that strategy, especially when is used on the offensive. There is another danger, people believing that have suffered certain fate real or imaginary might attempt to repeat that onto others. An old adage says that you test the worth of a man by granting him power, Mandela’s restraint is a case in point. True, give them power and see what they do with that power, especially with utterly defenseless people like Roma people in France, for instance, and also beyond. Finding common denominators is also a common technique to detect ‘intelligence’. On the other hand, I would like to propose an intuitive ‘definition’ for ‘intelligence’, I prefer the idea of ‘art’ because is universal. Cultures are based on art, and art is not a cacophonic arrangement of ideas combined at random lacking either plan or basic technique (Jazz has technique but not the plan and Piet Mondrian’s pictures (et al) have a plan but not technique, for example). Art is planned and people with sensibility do not need training to appreciate it. A westerner can easily appreciate Keops, or the Taj Mahal and Liu Ts’ai’s fishes; conversely, an Oriental person can appreciate Vivaldi, Bach and Mozart perfectly well; we can also appreciate art across time (Altamira’s paintings and good Picassos). What would do a Lascaux caveman genius with an ‘intelligence’ test ? I have an idea though. Well, I am running out of the number of characters graciously granted by Der Spiegel, so we must leave as it is, food for thought, but before we go let me express that I do not see Sarrazin as an exception but rather the norm of the XXI century, unfortunately. Norberto
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