Intelligence is inherited: the opinion of supporters of the hypothesis
Borislav Kozlovsky, "Snob"They don't become smart
Erudition is hardwired in the genes –
unlike the ability to solve puzzlesThis will never be told at school, because thereby they will completely discourage the desire to study: IQ is an innate thing by 80 percent: Plomin et al., Variability and stability in cognitive abilities are largely genetic later in life (about the exact figure, of course, they still argue).
The remaining 20 percent seem to depend on books, parents and teachers, but they are also a weak consolation: this is by no means "one fifth of the total intelligence", because calculations are carried out in units of deviation from the norm. Roughly speaking, if the "innate IQ" is 110 (and the norm is always 100), then the IQ of an adult will be squeezed in a narrow corridor between 108 and 112. In short, no matter how hard you try, you are either a smart guy from birth, or doomed to carry bags of potatoes all your life.
A new wave of rebellion against this view of things, where everything is too hopeless, was raised by four scientists from the University of Amsterdam. The team of professor-psychologist Han van der Maas found a weak point in the prevailing theory: IQ tests, on the results of which it is based (Kan et al., On the Nature and Nurture of Intelligence and Specific Cognitive Abilities). The tests have long been claimed that they are "overloaded with culture". In other words, the result of a diligent, dim-witted geek who just memorized a lot of facts will be better than that of a savage savage. Even if there are no questions about "the value of pi to the tenth digit" or "the distance from Moscow to Paris" in the IQ test, the result may still indirectly depend on mathematical literacy or the ability to read a map.
The idea was this: we will clear the tests from the oppression of culture – and find out how intelligence is transmitted in its purest form. This "in its purest form" has a strict name and an iron theoretical base under it. Cognitive scientists have been talking and writing about "liquid" intelligence since the 1970s - as opposed to "crystallized", based on erudition.
In search of "liquid" intelligence, van der Maas graduate students sat down to dig up old data from 23 studies on twins (there were 7852 test subjects). Why twins? Because they have the same genes to a single one. All the differences in intelligence that tests reveal cannot be attributed to any heredity – it is the same in twins.
The Minnesota Study of Twins Reared Apart, launched in 1979, turned out to be the most valuable source of information. The task was to find not just twins, but those who grew up in different families: for example, parents divorced or orphans were adopted by different people. There were 126 such pairs.
A real story about two of its participants – brothers Jim and Jim (pictured – VM), separated in childhood and met at the age of 39, roams the web. Without knowing anything about each other, they both married girls named Linda, named their eldest sons James and gave the same nicknames to the dogs.
But for scientists concerned about intelligence, another coincidence was more important: both received twos in English and fives in mathematics at school, and also fell in love with carpentry.
In Minnesota, the subjects were tormented with questions of various types: there was a game "find 10 differences", and the rotation of colored figures in the mind, and puzzles for folding paper figures. The authors of other studies on gemini raised from the archive were not so sophisticated, but the Dutch easily divided their questions into groups in descending order of cultural load: "vocabulary", "information", "understanding", "adding pictures", "sorting pictures" and a few more points.
That's where the surprise was waiting: it turned out that in tests with a high "cultural load", the twins consistently show the most similar results. Paradoxically, children who grew up in qualitatively different families (there were different numbers of books on the shelves, and they were taught differently at school) answered the questions as if they got the knowledge right in their mother's womb.
This idea smacks, if not mysticism, then Lamarck's theory of evolution: unlike Darwin, the classic believed that acquired traits are inherited. For example, knowledge: the father mastered the book – and the son has something in his head (even if he did not see his father in his eyes). But genetics seems to have put a fat cross on this idea for a long time, because there is no place to record a chronicle of successes, defeats and read literature in DNA.
Explanation without mysticism: what can be roughly described as a "craving for knowledge" is an innate property of the brain encoded in genes. It is inherited. And if you do not keep a person in deaf isolation, then, with the right heredity, he will extract enough information about the world from the most stingy stream of information. Here you can recall the story of Sofia Kovalevskaya, who studied mathematics by looking at formulas on the wallpaper in her nursery, or the future academician Israel Gelfand, who at the age of 15 in a village near Tiraspol got the first textbook on analysis, and at 19 entered the graduate school of Moscow State University. That is, a potential Lomonosov will not disappear even in a rural school in Brazil. But even the most beautiful developing gymnasium will add little to his talent.
Portal "Eternal youth" http://vechnayamolodost.ru28.10.2013