Today, we will be interested in the Intellectual Quotient – the famous IQ – because it has a central role in the High Intellectual Potential. This is basically the result of a psychometric test that would provide an indication of the intelligence of the individual being tested.
Before I begin, I would like to clarify two points that I find important. The first is that you will quickly realize that the IQ – at least its result – is not completely reliable. In reality, it is estimated that the score obtained is only about 70% representative of our "real intelligence". Thus, it is possible to pass the same test several times and obtain different results. That's why I don't devote a crazy cult to the intellectual quotient. Then, my second point, is that I will still talk about the results of this test. However, it is possible to misinterpret a bad score. Some people allow themselves to classify men according to their intelligence, and the results of the IQ tests have been the source of some racist theories. This is not the case. Again, I am not convinced by the value of the result, so I will not base and/or support a theory based on it.
Also, you will see that I have included greyed parts on this page. They correspond to a kind of FAQ around the intellectual quotient, and eventually allow a pressed reader to pick up only a few key points. Good reading.
What does IQ mean?
IQ meansIntellectual Quotient. It is the unit of measure of intelligence. It results from psychometric tests. Be careful, it's a good idea.quotientintellectual and notcoefficientintellectual.
Definition of IQ
As stated above, the intellectual quotient is used to measure human intelligence, which is measured itself through the General Factor, or Factor. g.
What is the Factor? g ?
I'm not going to go into the details because it's long and complicated (we may come back to it a next time, that said). What we must remember is that in 1904 a psychologist named Charles Spearman proposed the idea that all the mental performance of a person can be conceptualized into a single general skill factor: the Factor g. It's kind of like the power of a computer if you want. The more powerful the computer, the more its Factor g be raised. The tests of Intellectual Quotient therefore allow to measure this Factor g.
NB: I hope you noticed that the Factor g written with a small "g" in italics, not to be confused with Point G, which benefits from a large "g". Two rooms, two atmospheres.
The various IQ calculations
It is estimated that there are two ways to calculate the Intellectual Quotient: the classical IQ, and the standard IQ.
IQ classical, or mental age
The first, and also the oldest, way to calculate IQ is the so-called classical IQ, or mental age method. For example, a 10-year-old child who has the cognitive abilities of a 15-year-old child will have "15 years of mental age". To define this, he is presented with several items. Items of a child aged 10, 11, 12, 13, 14 and then 15 years. Those aged 15 must be stranded by almost all 14-year-olds, achieved by 50% of 15-year-olds, and achieved by almost all 16-year-olds. Simple, right? And to calculate this IQ, the following formula is used:
(mental age / real age) * 100 = Intellectual Quotient
Thus, if we take the example above, we can deduce that the child will have a classical IQ of (15/10)*100 = 150. The idea is easy to understand I find. On the other hand, it only applies to children as it will be more complicated to differentiate the mental age of an adult aged 50 from that of 55.
IQ by rank, become standard IQ
The second way to calculate the Intellectual Quotient is the IQ by rank. This method has become much more used (notably because it also works on adults), so it is called standard IQ. On this site, when I speak of IQ (only, without anything), I refer to this method and not to mental age. Here, the intellectual quotient is represented with the normal law (aka Gauss curve, aka normal curve). Fixed calibration (due to its construction) mean IQ in the middle of the bump. The standard deviation of 15, and the average intellectual quotient at 100, are generally used.
Understand that this is a historical and completely arbitrary measure, because it is estimated (yes yes, an estimate) that the distribution of IQ in the world is Normal. Thus, with a standard deviation (arbitrariness) from 15 and an average (arbitrariness also) to 100, the Gauss curve implies that:
- 68% of the population is located at a standard deviation of the average, thus between 85 and 115 (100 plus or minus 15);
- 95% of the population is located at two standard deviations from the mean, thus between 70 and 130 (100 plus or minus 15*2).
How do I calculate the IQ?
The IQ is calculated in two ways: Mental age (it is said that you are the mental age of someone of XX years), or by row (the global scale is based on the Gauss curve). There are several scales to calculate IQ by rank (as we do today). In all cases, the IQ is calculated with a psychologist.
Is the IQ innate or acquired?
We don't know too much.. The IQ seems mostly innate. Nevertheless, a variety of factors (biological, genetic and environmental) can influence this. Today, there are not enough studies and scientific evidence to give a firm and definitive answer.
Does the IQ have a curve shape?
We don't know.. The curve shape (the normal Gauss curve) is the current representation that is made because it is assumed that intellectual quotients are distributed in a normal way among all human beings. However, there is no evidence to justify it.
Settlement effect
Conventional and standard IQs (on the Wechsler scale) are relatively similar for median scores. For example, a child with an IQ of 110 on the Wechsler scale (so a standard IQ) will be close to an IQ of 110 mental age. It's another story when IQs increase. So, a 6-year-old girl with a standard IQ of 149 will have an IQ of... 179! This is why it is said that the standard IQ has a settlement effect on the IQ. As the IQ increases, the result will be lower than on an IQ of mental age. He's going down.
In particular, in order to limit this effect, Cattell developed a standard IQ with a standard deviation of 24 (not 15 as Wechsler).
Little story
The IQ is therefore an arbitrary measure that allows us to attempt to measure human intelligence. So how did we get there? For this, I propose a small historical page about the creation of this Intellectual Quotient.
Work on human intelligence begins at the end of the 19th century.nd century. The Englishman Sir Francis Galton (a cousin of Darwin!) is convinced that human intelligence is largely hereditary. So he's looking for a way to measure it to... improve the human species. Good atmosphere. Moreover, it is he who presents to the world the idea of eugenics (selection of individuals in a genetic way to eliminate those who do not enter into a predefined framework). Really creepy. Fortunately, he never managed to find an effective method of calculation.
In 1890, the American McKeen Cattell began to evoke the idea of mental age. But it was only in 1905 that two Frenchmen – Alfred Binet and Théodore Simon – developed the first usable test: the Binet and Simon test. They do so at the request of the State (in order to identify students with school difficulties) and this is why the classical IQ method is not valid for adults.
To address this problem, the American David Wechsler develops two new IQ tests per row: WAIS (Wechsler Adult Intelligence Scale) and WISC (Wechsler Intelligence Scale for Children). It is he who creates the standard deviation of 15, and the average at 100. It is these two tests which are still the most practiced (several others have been born in the meantime).
Factors influencing IQ
More and more studies show questionable and partial influences between a phenomenon and IQ. Some doubts arise because the correlations are really weak. On the other hand, one factor seems particularly important: the rate of myelination of the brain. Myelins are kind of membranes that connect the nerves of our brain. They therefore contribute to the rate of spread of the nervous flow which explains 50% of the Factorg, and finally the intellectual quotient.
So, in bulk, these are the factors that seem to influence IQ.
Biological factors
The thyroid system and melatonin seem important – whether it is the mother's during pregnancy, or the individual child and then adult. Subsequently, IQ may vary in adolescence, without knowing exactly why (food, alcohol, tobacco, drugs, social environment, etc.). Finally, the size of the brain seems to be important, and especially the volume of grey matter (neocortex).
Genetic factors
Part of the IQ seems hereditary, although this inheritance does not explain everything. If, for example, you have a gifted mother and a neurotypical father, then you are more likely to be in between. But the calculation doesn't work every time. For example, if your two parents have a weak intellectual quotient, there's nothing to say that you're not going to be gifted. Studies were conducted on homozygous twins raised (or not) in the same household. A correlation exists, but the intellectual quotients of separately raised twins are not identical so either the social environment plays a role or the IQ is not hereditary (or both). Mystery.
Environmental factors
There is still too little research on the subject. Nevertheless, pesticides and endocrine disruptors seem to have a negative effect on our intellectual quotients.
Is IQ genetic?
It seems. Parents' IQs appear to influence the child's IQ. Nevertheless, the scientific consensus does not yet have enough evidence to fully affirm it. In addition, some other factors (biological, genetic and environmental) also appear to be important. In all cases, the parents' IQ score does not provide a reliable definition of the child's IQ, or even a predictive range.
Does the size of the brain matter with the IQ?
Yes. Or at least we think so. In fact, it seems that it is mainly the volume of grey matter that plays an important role on IQ (not the whole brain).
How to increase your IQ?
We don't know.. The influence of the outside world on our intellectual quotient is still mysterious. Nevertheless, there is much to bet that a healthy lifestyle can only do good.
Factors influenced by IQ
It seems that our personalities are partly influenced by our IQ. Individuals with a rather weak intellectual quotient have broadly identical personalities. This is not the case for people with high intellectual quotients: their personalities are more varied. I explain: there is more difference between people with IQs of 140 and 160 than two people with IQs of 100 and 120. One can imagine that high IQs are therefore more sensitive to their environment in creating their personality. This joins the hypersensitive characteristics of zebras, gifted and other high intellectual potentials. Indeed, hypersensitivity and emotional potential are important characteristics of people with high potential with high intellectual maturity.
IQ tests
I quickly approached the various existing tests to measure the intellectual quotient. In this part, I will go a little deeper on the subject and on the interpretation of the results. It is also possible to test its high potential via clinical approach.
I also allow myself to make a small part of the link between the school and the intellectual quotient. Testing the potential of a (potential) adolescent or early child usually occurs in two situations. (1) The first is when early students are in a failure situation. Because of their different cognitive functioning, children with high potential experience boredom at school – the school system is not for them. Or they have different dys (dyslexia, dyspraxis, etc.), ADHD (Disability of Attention / Hyperactivity), or a strong lag with others. (2) The second is when intellectual functioning succeeds in today's society, and the gifted child demonstrates incredible academic success (with class jumping). In any case, taking a psychological assessment that will allow the correct diagnosis to be made seems to me a priority in order to detect the potential.
Why take an IQ test?
Depends. There is no specific reason, it depends on everyone. Some may want to satisfy a need for curiosity, while others may want to "check" the potential presence of High Intellectual Potential For example. In any case, if you have any doubts about an intellectually early child potential, go because understanding the potential will help to grow into a gifted adult.
Can I find a free intellectual quotient test?
Yes, but no. Search on the internet and you will find a multitude of free IQ tests. Nevertheless, a "true" IQ test must be done by a graduate psychologist. So yes you can find a free intellectual quotient test on the internet, but it will not give you a valid result.
How much does an IQ test cost?
At least €200 or more. That is why it is important to be certain of its motivations before launching it.
Understanding the different tests
There are many different IQ tests. Nevertheless, the best known are:
- Wechsler tests (WAIS and WISC). These are IQ tests per row with an average of 100 and a standard deviation of 15;
- The Cattell test: also an intellectual quotient test per row, but with an average of 100 and a standard deviation of 24.
You can only pass it to a graduate psychologist and if possible specialized in IQ testing. And be careful, it costs a lot (count 2-300€ easily).
Composition of an IQ test
An intellectual quotient test is usually composed of several sub-tests (called Subtests). Each subtest is oriented around a particular axis. For example:
- Subtests related to performance to test memory or buildability. Typically, you can be asked to remember and return as many numbers as possible of a suite, or build a kind of puzzle, or reconstruct an image with cubes, etc.
- Logical subtests: find the next digit of a sequence of numbers (a priori without logical follow-up).
- Verbal subtests linked around the language, such as finding the word that does not belong among others.
The overall test may take place in one or more sessions. There's really no rule. Thereafter, it is up to the psychologist to appreciate your results and give you your score. If you get a score that is substantially the same as the different tests, we will talk about homogeneous results. If they are not identical, you will have heterogeneous results. We also speak of laminar or complex intelligences.
Limits of an IQ test
The limits of these tests are (in my opinion) very numerous. First of all, I find them too related to the state in which you are when you pass it. With stress or fatigue, it is most likely that you are more in trouble than if you were in good shape. Second point, some categories are difficult to notice and the psychologist who gives you the test can therefore vary your result. Finally, the language barrier can be a huge barrier for people who pass it in a language that is not their mother tongue. Moreover, Cattell's test does not pass a verbal subtest in order to limit this effect of linguistic bias. They say he's acultural.
Interpret the results of an intellectual quotient test
We just saw that the IQ test has several limits – too much in my opinion. Thus, the overall result is to be taken with tweezers. Instead, I recommend studying the results of each subtest and discussing them with the person who passed them on (and paying attention to the IQ classification). She is the one who will be most able to give you a precise account, not what you can draw from a score on a piece of paper. Also remember that if you go back to the test, you probably don't get the same result. It's normal, you'll have done it under different conditions. In addition, it is estimated that the result is only 70% of your "real intelligence".
For all these reasons, I chose not to talk about my IQ score. I do not think that it affects the gift which, in my opinion, is rather based on a feeling than on a variable number. Despite this, I fully understand the need for some to put a number on what they feel. It always feels good. I just highlight the fact that this number has a variability that I consider too important to be taken seriously – even if I agree with you, it can give a real trend.
What is a high IQ?
130. High intellectual potentials are generally considered to have an intellectual quotient greater than 130 (on the Wechsler scale).
What is the average IQ of a person?
100. It is considered (arbitrarily) that the average IQ of a person is 100 on the Wechsler scale. But this is only a scientific consensus.
What is the IQ of a gifted one?
130 and over. It is generally considered that gifted, early or high potentials must have an intellectual quotient greater than 130 (on the Wechsler scale).
How does IQ evolve with age?
It's dropping., or at least that's what we think right now.
What is the IQ of an Autistic Asperger?
70. In order for an individual to be diagnosed with High Level Autism or Asperger Syndrome, his or her intellectual quotient must be greater than 70 on the Wechsler scale (in addition to the other usual criteria for diagnosis of autism).
The limits and criticisms around IQ
Even if the idea of measuring intelligence seems, why not, to be a good thing, the intellectual quotient is regularly strongly criticized. Here are the main causes.
Lack of a global and common definition of intelligence
First, scientists fail to agree on a definition of intelligence. And if we don't know what to measure, you will agree that it can be difficult to measure it. In fact, this lack of definition is due to the fact that intelligence remains a major subject of scientific debate. Many major issues remain unresolved.
Cultural bias
This point can be defined in two subparts. First of all, there is a cultural bias in the very definition of intelligence (which contributes to the absence of a scientific consensus, as mentioned above). Depending on where we are in the world (so according to the culture of the country), intelligence will have neither the same value nor the same definition. Should intelligence be measured according to the criteria of those who created the IQ scales?
Secondly, and I mentioned earlier, there is a cultural bias in particular in the verbal subtests present in certain verbal QI tests. If you pass the intellectual quotient test in a country where your mother tongue is not spoken, you can actually be disadvantaged (without affecting your real level of intelligence). You just don't speak the language well. I'm sure I won't get the same results if I go back to the same IQ test in Spain as I did in France. Yet I'm just as smart. To limit these effects, Cattell's test does not propose verbal subtest – it is acultural.
Problems raised by scales: variance and high scores
IQ scales are also limited. Already, there is a difficult variance between several tests. If you pass the same test twice, you may not get the same results. This can be due to the presence or absence of stress, fatigue, agreement with the psychologist, appreciation of the same psychologist, etc. And that, scientifically, is not great. Another problem is that the accuracy of the scale when arriving on high IQs can be improved.
The myth of the Flynn Effect
James Flynn is an American. He noted the overall (global) increase in IQ scores throughout the 20th century.nd Until the early 1990s. This increase is called the Flynn Effect. In seeking to understand why the 1990s marked the end of cognitive growth, researchers have identified several possibilities:
- Changing power models with globalization;
- Influence of new stimuli from a young age (including TV screens, computers and smartphones);
- Correlation with increased lifetime.
The reason is in fact quite different: the Flynn effect has never really been validated, and the intellectual quotients of our planet have stopped falling. Flynn would only have been interested in the weakest intellectual quotients (which they did increase by improving living conditions). However, the overall average has declined. In addition, IQ scales have been regularly updated, distorting overall studies over several decades.
Why is the IQ decreasing?
We don't really know.. However, it seems that the influence of new stimuli (screens in particular) on young and developing brains as well as more repeated contacts with certain endocrine disruptors and chemicals are not for nothing.
How does IQ develop during depression?
It's dropping.. It seems that IQ is falling during depression. This decline is even greater in bipolar disorders.
Is the IQ reliable?
Not really.. The results can vary according to many factors (fatigue, stress, psychologist, cultural bias, etc.) without your intelligence being changed. In addition, scientists do not so far agree on a precise definition of intelligence. It is difficult to measure something that is not yet well understood.
Average IQ
Finally, we start the last part of this article (and the one I find the most funny) around the Average IQ. The idea of this study is to look at the impact that this intellectual quotient can potentially have on a population, a profession or a country – not to draw risky conclusions. Averages of intellectual quotients should therefore be taken with tweezers.
Averages by country and occupation
First, we'll talk about the average IQ per country. In France, we have an average IQ of 98. This is not too bad, as it seems that the average per country is between 84 and 88. The winners are in East Asia: Hong Kong (107), South Korea (106), Japan (105), and Taiwan (104). You will notice that I said the average IQ per country is between 84 and 88. So why not 100, as indicated on the IQ curve earlier? Simply because this is a country average, not the number of inhabitants. For example, the Chinese have an average IQ of 100 and (as long as they are a lot) will significantly increase the average if one takes an average per inhabitants.
Now let's take a few IQ averages per occupation. In the United States, the average physician has 114, dentist 108, physiotherapist 111, and dietician 91.
What is the average IQ of the French?
98. The average intellectual quotient for French is 98 on the Wechsler scale.
Why is the French IQ falling back?
We don't really know.. Nevertheless, it is possible that this is for the same reasons as the decline in IQs around the world: too many screens and chemicals in our daily lives.
What is Japan's average IQ?
105. Japanese, often taken as an example, have an average IQ of 105 on the Wechsler scale.
Records
Some records now. Attention, however, the tests were carried out with the Cattell scale (not the Wechsler scale). Thus, the results obtained are more impressive. The best of the best seems to be Australian mathematician Terence Tao with an IQ of 230 (loan of 180 at Wechsler). It is followed by Kim Ung-Yong with an intellectual quotient of 210 (which would make about 160 with Wechsler). He was even hired by NASA when he was nine! Normal.
For the weakest IQ, it's very hard to say. Indeed, they are generally not measured and so I find no archive about it. Sorry.
Who has the highest IQ in the world?
Terence Tao. It is the Australian mathematician Terence Tao who peaks at 230 on the Cattell scale, or about 180 on the Wechsler scale.
Who has the lowest IQ in the world?
We don't know., because no one rushes to get tested in case of suspicion of IQ too weak.
Who has an IQ of more than 200?
Few people. Indeed, such high intellectual quotients are very rare. After that, everything depends on the scale to which they are measured.
Star IQs
Now let's talk about our little celebrities. Obviously, everyone explains having a (very) high score. So we could legitimately ask ourselves a few questions. (1) Are all intellectual quotients on the same scale? Probably not, as some high scores don't seem feasible at Wechsler. But even by putting them on the Cattell scale (which is likely with Anglo-Saxons), these results are incredible. So (2) are all public characters gifted or (3) are they all laughing at us?
What was Albert Einstein's IQ?
160. It is estimated that Albert Einstein had an intellectual quotient of about 160, but this is only an estimate.
What was Stephen Hawking's IQ?
160. As with Einstein, it is estimated that Stephen Hawking had an intellectual quotient of about 160, but this is only an estimate.
What is Adriana Karembeu's IQ?
120. During a television show on France 2, Miss Karembeu performed an intellectual quotient test and learned that she was actually in the top of the range: 120.
What's Bill Gates' IQ?
160. Bill Gates, the founder of Microsoft and one of the world's largest fortunes would have an intellectual quotient of 160.
What is the IQ of the Bogdanov brothers?
190. They reported having passed an IQ test at age 11 and being part of the 0.01% of the population with a very high IQ more than 190.
What's Elon Musk's IQ?
ManyAt least this is what some seem to estimate.
What's Jodie Foster's IQ?
132. This is also what earned him his (more than deserved) gifted actress.
What is Jeff Bezos' IQ?
Outside the common. He never revealed the result, but it seems that when he was tested at the age of 8, the result was "out of the ordinary". Mystery.
What is Garry Kasparov's IQ?
190. Uncontested champion of chess, Kasparov would have an extraordinary intellectual quotient of 190.
What's Kanye West's IQ?
132. Kanye West said, at a recent conference as part of his candidacy for the US presidential election, he had an IQ of 132, which would make him a " Engineering while making his life complicated because his " brain is too big for his skull And he had to go to the hospital.
What is Kim Namjoon's IQ?
148. The South Korean artist would have an IQ of 148, well above average.
What is Koko Gorilla's IQ?
70-95. Koko, the famous gorilla who spoke sign language, had an IQ between 70 and 95 (possibly more than much of humanity, just that).
What is Leonardo da Vinci's IQ?
220. Some concluded that Leonardo da Vinci must have an intellectual quotient of 220.
What's Marilyn Monroe's IQ?
165. His IQ was also higher than that of Einstein. No wonder she ended up jumping to the White House!
What is Nabilla's IQ?
160. We found our new Einstein. Blague aside, it's an incredible woman business.
What is Barack Obama's IQ?
137. The figure does not seem official, but several sources report a very high IQ. Yes he can have an IQ of 137.
What's Rowan Atkinson's IQ?
173. Mister Bean is actually not that simple, because Rowan Atkinson would have an intellectual quotient of 173.
What's Sharon Stone's IQ?
154. One more proof that incarnation of ingenious characters does not mean that one can't have been gifted.
What is Donald Trump's IQ?
« One of the best and you all know it. ». In the continuation of his Tweet, he recommends that we not " feeling stupid or unsure of ourselves "For " It's not our fault. " A genius.
What's Uma Thurman's IQ?
183. Now she's not just a little gifted! Kill Bill also has under his blonde hair.
What's Mark Zuckerberg's IQ?
152. This is in any case the most recent estimate.
Conclusion
In conclusion, the Intellectual Quotient (IQ) allows to measure intelligence through the measurement of the Factor g. It is therefore not a precise measure, because it does not measure the object directly but rather something in correlation. In the idea, it's like you have to measure your size according to your shadow. Moreover, the lack of scientific consensus on the definition of intelligence, as well as the various biases and variables that may occur in an intellectual quotient test, mean that this is only an approximate measure. It can, however, give a trend, but not a definitive measure.
A high IQ is normally the only gateway to the High Intellectual Potential. However, because of all these variables and inaccuracies, I think that the doubt should be felt rather than measured.
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