Do they stupid from coronavirus?

A group of scientists from the UK conducted a study on the negative impact of coronavirus on the level of intelligence - its results were published on the website of the authoritative medical journal The Lancet and were widely discussed in the Russian media. The authors of the work revealed significant signs of the deterioration of intelligence in the ill -fed and came to the conclusion that the changes are long -term. Problems with memory and attention were talked before before, but this is the first full scientific research on this topic.

Why is the work of British scientists important, but at the same time it has significant gaps, is it about the deterioration of intelligence as a whole or about the fall of only some indicators and is the mental abilities really not restored after the illness? “Paper” discussed an article with a researcher at the Cognitive Research Laboratory of the RANEPA and the candidate of psychological sciences Ivan Ivanchey.

- What theses of the article by Lancet, in your opinion, deserve the most attention?

- The article was actually published not in Lancet, one of the main medical journals in the world, but in Eclinicalmedicine , which is published by the Lancet Publishing House as an additional magazine. It is new and much less prestigious, so it is not necessary to assume that this is a very authoritative publication. Obviously, the article attracted a lot of attention, because it was published on the Lancet website, but they are actually connected only by the publishing house. Which, of course, does not worsen its quality.

This article is one of the first attempts to systematically evaluate the negative effects on the psyche and cognitive processes that follow Covid and its different currents. In this sense, this is a very important job. Prior to this, there was a lot of clinical evidence that the long -term negative consequences have long -term negative consequences, including cognitive processes. But these were data from doctors, not systematic scientific research.

The authors tried to apply polls similar to the intelligence test with various cognitive tasks on a very large sample (more than 80 thousand people). We looked at how these tasks are affected by the fact that people have been ill with Covid. The results show a fairly clear dependence between the severity of the course of the disease and how much the level of the tests deviates from the expected. That is, the heavier the person was sick, the stronger the decrease in cognitive indicators.

- What are the gaps in the study?

- In the [studied] groups, there is a decrease in intellectual indicators - but this is not entirely correct formulation. Because if we are talking about a decrease, then there should be two measurements: before the disease and after. But the authors measured the solution of the problems only once and then looked whether the person was sick before or not. At the same time, in a group where people were seriously ill, respondents could be initially low with low indicators. You can even come up with a reasonable explanation: for example, the same people who did not believe in the seriousness of the disease did not take any safety measures - they did not perform a cognitive test well.

The authors are trying to solve this problem with the help of statistics: they show that in all demographic and social indicators these people should have intelligence on average higher than what they received. This is a normal approach, but not superpowial. It would be much more convincing to make two measurements: before the illness and after the illness. But you yourself understand, it is difficult to do it, because we never know which people get sick.

In addition, the test that is used in the study is Great British Intelligence Test - not common and not exhaustive. In the article you can see what tasks there were: spatial thinking, for short -term memory, and thinking by analogy. But, for example, there are no tasks for things that often worry people after Covid: concentration, the ability to remember or recall the information.

“When this article came out, it was retold in the media with headlines in the spirit of“ Scientists proved that coronavirus causes a deterioration in intelligence. ” I understand correctly that it is incorrect, this thesis is not proven and can there be nuances?

- correctly, I would say this: people who have been ill with coronavirus have some reduced cognitive indicators. We are not talking about intelligence as a whole, but about individual cognitive functions.

According to the schedule in the article, you can see that the most powerful decrease in the indicators had people who were hospitalized and connected to the Ivl. They have a decrease by 0.5 sigma. In Sigma statistics, this is a standard deviation. If we take all the people who performed the tests and take the average value, then about 70 % of people will lie in the plus or minus one sigme. If you have a plus of two sigma to the average indicator, then you have passed the test better than 99 % of people.

Immediately there was a decrease in the alleged intellectual abilities by 0.5 sigma. If you conditionally evaluate the intelligence on a 10-point scale and you had 9 out of 10, then it became 7.5–8. Not much, but noticeable.

- And what is generally understood by intelligence and cognitive functions?

- This is a difficult question, researchers have been trying for many years to understand how it is best to measure intelligence. Cognitive functions are a different name for cognitive functions. That is, all the functions of our brain and psyche, which are aimed at processing information, making decisions, remember and remember.

The authors of the study tried to collect different tasks. But for the most part, verbal, spatial abilities, tasks for memory there, for example, were evaluated for the most part. That is, this is an attempt to evaluate the elementary cognitive processes that we use every day.

- The mechanism of the influence of coronavirus on the brain and the nervous system is still incomprehensible?

- Yes. There are already some studies that show what changes in the nervous system occur when coronavirus enters the body, but they are still small and not giving final conclusions. In the work of British scientists, the mechanism has not been studied in any way.

If we conduct the same study, for example, after the influenza epidemic, it may turn out that hospitalization with influenza would also lead to a decrease in cognitive functions. This may not happen because the influenza virus enters the nervous system and affects the brain. Imagine that you are hospitalized with a serious illness for three weeks-and after that you are asked to take some tests. Even if not immediately, but after a few months. It is possible that your body is still restored and now you are not up to cognitive tests, you have a low motivation for their implementation, a low concentration of attention, simply because you suffered a serious illness.

This study does not exclude the possibility that any severe infectious disease can reduce the performance of intellectual tests.

-The article caused resonance even due to the thesis that the deterioration of intelligence is long-term. How appropriate is the thesis that intelligence is not restored after coronavirus?

- Almost no. The source of data on this occasion is the fact that they took these measurements throughout 2020. Some people, for example, were sick in the spring-and after a few months they still show reduced test results. Hence the conclusion about the long -term.

The pandemic is only the second year, so I would not replicate this conclusion. But the only reliable option to say how long the consequences of the disease are to wait a decade after the pandemic.

Another way out is to see the mechanisms of changes in the nervous system. Knowing about these processes, we can say whether they are reversible or not. Such neurophysiological studies could give an answer about long -term. But while the conclusions are premature.

- How important is it for scientists to establish the influence of coronavirus on intelligence? How much is this topic under discussion and is it worth waiting for new research on it?

- This is a very discussed topic. But in order to draw reliable scientific conclusions, we need controlled research.

It is difficult to conduct experiments with the disease. So you need to better analyze the data. And from the point of view of reliable conclusions, there have not been so many time. It is very difficult to conduct studies that would give a clear answer to questions about a decrease in cognitive functions due to Covid, but they will be one hundred percent. This was the first attempt by a large -scale systematic study.

Photo on the cover: frame from the movie " Idiocracy "

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