Next time someone tries to sell you a book or device in order to retrain your supposedly flabby right hemisphere, take out your wallet. And then press it firmly against your chest and run away with your strength. As in some other myths, there is a grain of truth in this too. However, this grain will probably be difficult to find under a pile of disinformation, which was falling asleep.
Is it true that some people have a better-left hemisphere, while others have a better right hemisphere? There is reliable evidence that the two sides of the brain, called hemispheres, differ in their functions. For example, when different hemispheres are damaged, it affects different abilities.
And tomography shows that when people perform different thinking tasks, their hemispheres behave differently. Of course, the most dramatic evidence of brain function asymmetry - the superiority of one or the other hemisphere in the performance of certain tasks - is given by patients who have undergone "brain decomposition" surgery.
In this procedure, surgeons separate the nerve pathways that connect the opposite points in the left and right hemispheres of the brain in a final attempt to take control of a severe form of epilepsy.
Tomography shows that when people do different thinking tasks, their hemispheres behave differently.
The connecting hemisphere, which is the main purpose of this operation, is the corpus calcium body.
Roger Sperry received the Nobel Prize in 1981 for his landmark research on patients with split brains. Once they recovered from surgery, they seemed deceptively normal in their daily activities. But as soon as Sperry tested them in the lab, it turned out that two halves of their brains were working independently. Each half acted without understanding or knowing the other.
In Sperry's laboratory tests, patients looked at the center of the screen, where the researcher briefly highlighted words or pictures. At a fixed glance, the information displayed to the left of the fixation point goes to the right hemisphere, and the same is true for the information provided to the right of the fixation point.
In more familiar situations, this separation does not occur because patients are constantly shifting their gaze on their surroundings. As a result, information usually reaches both hemispheres. When this is not the case, some very specific things can happen.
The right hemisphere receives information and controls the movements of the left side of the body, and the left hemisphere does the same with the right side. Almost all right-handed people and most left-handed people have primary areas for receiving and processing language messages in the left hemisphere. Thus, if we limit new information to the right hemisphere, the left hemisphere, which is more verbal than the right hemisphere, will not be able to tell us what information has been received. And we will be surprised to see how the left-hand moves from isolated information for reasons it cannot understand.
For example, if a researcher shows the right hemisphere of a naked person's brain-damaged subject a picture of him or her, he or she may giggle. However, when asked why she is giggling, she (i.e. her left hemisphere) will not be able to explain this. Subjects with a split-brain may even do something with their right hand, such as putting together a piece of dice, with no idea that their left hand will destroy the piece in a few seconds. All this is proven. The argument concerns the uniqueness of the tasks performed by these two hemispheres and how they do it. In this respect, brain researchers have become more cautious in recent years, while many popular psychologists seem to be "off the chain.
Using Sperry's methods, researchers have confirmed that the left and right hemispheres perform relatively well in different ways. The two halves of the brain are different in how they handle tasks, not what they handle.
The left hemisphere has a better understanding of specific features of speech, such as grammar and word formation, while the right hemisphere has a better understanding of intonation and accents of speech. Although the right hemisphere manifests itself better in the implementation of non-linguistic functions that involve the visual complexity and spatial processes, the left hemisphere also plays a role in this, if we give it such an opportunity. The right hemisphere better understands the general feeling of space, while the corresponding areas in the left hemisphere become active when a person determines the location of objects in specific places. In many cases, it is not that one hemisphere or another cannot accomplish a task, but that one of them can accomplish that task faster and better than the other.
The tendency of psychologists to attribute all mental abilities to the individual right and left hemispheres is probably more relevant to politics, social values, and commercial interests than to science. Critics have called this extreme view a "dichotomy".
Popular psychologists have also described genuine differences in the way the hemisphere processes information, declaring the supposedly cold and rational left hemisphere as "logical," "linear," "analytical," and "male," and the supposedly warm right hemisphere as "holistic," "intuitive," "artistic," "spontaneous," "creative," and "female. Claiming that modern society underestimates the emotional perception of the world typical of the right hemisphere, supporters of the dichotomous approach began to promote bizarre schemes to increase the activity of this hemisphere. Their books and seminars promised to free us from the barriers to personal growth imposed on us by the inflexible school system, which approves of "left-hemispheric thinking".
However, a group of experts assembled by the American National Academy of Sciences came to the following conclusion: "...we have no direct evidence that we can teach the use of the brain hemispheres separately. And that training behavior could probably improve different styles of learning or problem solving, but such improvements have nothing to do with the difference in the functioning of the two hemispheres.
A practical result: Do not go for the dichotomous approach of those who need to earn money in the workshop, or for those who advertise different things to synchronize the activities of the hemispheres, whose promises sound too good to be true. Current research into the differences between hemispheres, even by those responsible for discovering the specialization of the left and right hemispheres, focuses on showing that the brain works as one.