Can someone's IQ rise or fall?

Medical Video: Jordan Peterson - Is Increasing IQ Possible?
Can a person's IQ change?
Various theories about IQ
Theory 1: Intelligence is measured by ability, not just knowledge
Theory 2: IQ increases 3 points every decade
Theory 3: Experience and formal education can change IQ
Theory 4: IQ does not exist, and the IQ test results are relative
Theory 5: We can train ourselves to improve intelligence

Medical Video: Jordan Peterson - Is Increasing IQ Possible?

When we grow up, the institution in which we study usually tests intelligence on students, also known as IQ tests. Have you ever taken an IQ test many times? How is the result? Stay the same, increase or even decrease? Why is that so? Some studies say that IQ changes with age. However, what you need to know is that intelligence is not determined from birth.

Can a person's IQ change?

When children and adolescents, a person's intelligence tends to be vulnerable to change. So, it's still very possible to change. In children, the relationship between brain size and IQ is not very influential, compared to adults. IQ itself is associated with brain development in a complicated way. A study cited by the Psychology Today website, with children's participants, found that 7-year-olds with high IQs (more than 120) tended to have less cortical thickness, but afterwards found also an increase in cortical thickness in children with High IQ.

According to, Nicholas J. Mackintosh, an IQ researcher, in his book IQ and Human Intelligence quoted by Psychology Today, if your IQ at the age of 40 is still the same as your IQ when you are 10 years old, then there is something seriously wrong in your life.

Various theories about IQ

A series of IQ tests are believed to be valid results for knowing one's interests and intelligence, is that right? For more details, the following are the opinions of several researchers quoted from the Live Science website:

Theory 1: Intelligence is measured by ability, not just knowledge

According to Jack Naglieri, research professor at the University of Virginia, IQ can change depending on several factors. The best way to measure intelligence is to measure abilities that are based on the knowledge he gets, separate from the knowledge he has. Sometimes, intelligence is obtained not because these children are taught to be smart, intelligence is obtained by teaching them to use what they have efficiently. According to Naglieri, people find it difficult to distinguish between ability and knowledge. A person can learn and improve vocabulary, but that does not necessarily make him smarter.

Theory 2: IQ increases 3 points every decade

According to Richard Nisbett, lecturer in psychology at the University of Michigan, IQ can change at any time. However, IQ tests often produce the same results, even after years of trying again. However, the more you mature, the stability will affect the outcome of the score. So, the average IQ of each person will experience changes over time. In modern society, capabilities are increasing, so it is very possible IQ increases 3 points per decade. The study revealed an 18-point increase in the average IQ of people living between 1947 and 2002. The average IQ of people aged 20 years in 1947 was lower than those of 20 years living in 2002. However, for cases IQ as a measure of intelligence, Nesbitt is not yet sure about its validity.

Theory 3: Experience and formal education can change IQ

According to Stephen Ceci, lecturer in psychology development at Cornell University, after conducting research by observing participants from small to adult for years as the object of his research, it was evident that there was a change in the verbal area in the brain, so adolescents experienced an increase in verbal IQ. According to him, many studies show IQ can change. There are several factors that correlate with IQ changes, one of which is a change in the way he is taught in school. Children who are taught in a systematic rather than thematic way, usually experience an increase in IQ. Because, systematic patterns are more influential in some IQ tests.

Also found are several studies that show brain changes. A taxi driver in London has a brain change when his brain isscan after and before driving activities, when he must learn to navigate the labyrinthine road in London. This is triggered by the navigation capabilities used. According to Ceci, life experiences and experiences related to one's school years can change a person's brain and IQ.

Theory 4: IQ does not exist, and the IQ test results are relative

Unlike the opinions of previous experts, according to Alan S. Kaufman, lecturer in clinical psychology at Yale University School of Medicine, there is no such thing as IQ. The concept of IQ itself is relative. IQ is only a representation of how well you do something, whereas IQ tests are only a comparison with people of your age. We cannot swallow a whole IQ test result, for example a score of 126, because a reliable IQ test also gives you a 95% confidence interval. So, you can say that with these 95% intervals, someone with an IQ score of 126 might have an IQ between 120 and 132.

Theory 5: We can train ourselves to improve intelligence

Kevin McGrew, leader of the Institute for Applied Psychometrics, said that IQ changes depend on several things. According to him, it is important for us to distinguish between two different types of intelligence. There is something called biological intelligence, in this case defined as nerve efficiency. In addition, there are psychometric intelligence - measured IQ scores, this is a method that is indirectly and imperfectly used to estimate your biological intelligence.

The question now is, can we improve biological intelligence? Various studies have been conducted over the past few decades using neurotechnologies (programs that know how to understand the brain based on various aspects), are very likely to improve the efficiency of your nerves. Your cognitive functions can be trained to work more efficiently.

The other question now is, can someone's IQ change? The answer is yes. Changes in the score may not be based on real changes in intelligence as a whole, but rather caused by differences in tests used to measure different abilities. There are some more stable abilities (for example verbal abilities), some are less stable (for example cognitive speed in processing, short-term memory).

The important thing is that you know how to use your intelligence, not just having a certain level of intelligence in general. The question you can ask yourself is, how well do you plan? How well do you respond if the situation doesn't work? These non-cognitive properties can change your cognitive abilities.