Thanks to popular psychology, it is widely believed that the tendency towards creativity or science depends on which hemisphere of the brain is more developed. We decided to figure out whether there are “right-brain” and “left-brain” people.

The idea that the brains of artists and thinkers work differently has been around for a long time. For example, Russian physiologist Ivan Pavlov assumedthat the left hemisphere dominates thinkers, and the right hemisphere dominates artists. In the second half of the 20th century, such hypotheses seemed to receive scientific confirmation: in 1973, an article was published in the New York Times “There are two surprisingly different people living in our heads.”. It was dedicated to the work of Roger Sperry, who in the 1960s studied people with split brains. He observed how the functioning of the nervous system changes if the corpus callosum, which connects the two hemispheres, is cut. A New York Times journalist summarized the results of his research as follows: “Each of us is capable of two incompatible styles of thinking, two separate learning mechanisms.”

At the same time, the belief was established that one hemisphere dominates the other, and this affects the choice of profession and the way of solving certain life problems. Subsequently, books based on this belief began to appear, the authors of which promised to develop the right or left hemisphere: "Efficient brain. Right brain vs left brain", “Superbrain: training the right hemisphere, developing the left hemisphere” etc. It’s easy to find on the Internet tests, allowing you to recognize your dominant hemisphere, or teaching methods, taking into account this feature of the brain.

American neuropsychologist Roger Sperry in the 1950s observed monkeys and cats with a dissected corpus callosum connecting the hemispheres. The scientist noticed that in this case, the hemispheres learned separately and perceived information differently. These results were met with skepticism, partly because in the 1940s, treatment for intractable epilepsy 26 patients The corpus callosum was incised, and after the operation (called a commissurotomy), none of them showed any neurological or psychological consequences. These and other data have led some scientists to the conclusion that the hemispheres are equipotential - initially perform almost the same functions.

In the 1960s Sperry started researching brain function in people who survived commissurotomy. During experiments, he and his assistants noticed that the hemispheres have their own functional specialization: right allows you to navigate in space, paint, recognize faces, perceive music, be aware of social relationships, and the left - understand speech, analyze events, carry out mathematical calculations, give explanations and solve logical problems. In 1981 Roger Sperry for his research received the Nobel Prize in physiology and medicine.

Popular psychologists have glossed over existing differences in how the hemispheres process information. Because of this, the left began to be considered cold, rational, logical, masculine, and the right - holistic, intuitive, spontaneous, creative, feminine. In this interpretation, it turns out that the hemispheres unite two different subpersonalities: one (left hemisphere) is an analyst and accountant, and the other (right hemisphere) is a free artist and Zen master. And depending on which hemisphere dominates, a person exhibits either a craving for science or artistic inclinations.

However, the point is not that one hemisphere performs some tasks and fails to cope with others, but that it solves some tasks faster and therefore takes the initiative. In normal people who have not undergone corpus callosum splitting surgery, the two hemispheres exchange information during most tasks. In a person with a split brain, cooperation between the hemispheres is impaired, so it becomes noticeable interhemispheric asymmetry.

In 2013, a group of scientists led by Jared Nielsen published a study, which finally refuted the idea that in humans one of the hemispheres predominates. Neurologists conducted MRI scans of the brain in 1011 people aged 7 to 29 years. The subjects were at rest or reading a book, and the scientists observed the activity of different areas of the brain. As a result, no clear evidence was found that some people have a more developed neural network in the right hemisphere, while others have a more developed one in the left hemisphere.

Let's summarize. Modern researchers agree that the two hemispheres differ in how they process tasks, not in what specific tasks they solve. So, in the case of speech, the left hemisphere knows better the rules of grammar and methods of word formation, while the right hemisphere knows better reads intonation and the emotional component of the statement. Although there are differences between the hemispheres, a healthy brain works in an integrated manner.

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