It is known that the left and right hemispheres of a person have different functions, which, however, are complementary. Asymmetry is a phenomenon that is inherent in the brain of not only humans, but also animals. Moreover, the left hemisphere is not a mirror image of the right one and vice versa. The hemisphere in which each individual has a speech center is dominant. In the vast majority of cases, this role is played by the verbal-logical left hemisphere.
Connections between the hemispheres
There are some interesting facts about the connections that exist between the two halves of the brain. First, the left hemisphere is always slightly larger than the right. Secondly, in the right hemisphere there are long nerve fibers that connect it with the left. The left one, on the contrary, contains a large number of short fibers that create connections in limited areas. Brain asymmetry is a process that takes an average of ten to fifteen years to form. Sometimes its speed can be due to genetic characteristics. It is practically not observed in infants. Asymmetry is an acquired quality. In addition, it has been proven that in illiterate people it is less pronounced. That is, in the process of learning andacquisition of new knowledge the brain becomes more and more asymmetric. Those who do not pay due attention to education slow down the development of many important functions.
Opening asymmetry
Asymmetry is a feature that has always interested scientists. But up to a certain point, it remained a mysterious object that could only cause a lot of assumptions even among the brightest minds of mankind. The history of the development of this area began with the discovery by Paul Broca of the relationship between human speech and the use of the right or left hand. This happened in 1861, when a scientist discovered that his patient, who suffered from loss of speech, had lesions in the left hemisphere of the brain.
Also, the connection between the two parts is carried out with the help of a special bundle of neurons - the corpus callosum. Thanks to him, they work harmoniously, as a whole. Some seriously ill patients underwent an operation to dissect the corpus callosum. This made it possible to study in more detail the features of the right and left hemispheres.
Split-brain experiments
Functional asymmetry manifests itself in a completely paradoxical way. For example, it turned out that the left hemisphere is responsible for building logical connections, mathematical calculations. It “understands” any complex speech well. The right hemisphere, on the contrary, can recognize only the most general connections. When presented with the most common objects - a spoon or a ball of thread - it can assign them to a certain class. The advantage of the righthemisphere is an excellent orientation in space. An experiment was set up: patients with a medically split brain were asked to assemble a structure according to a drawing with their right hand. In doing so, they made many mistakes. This was due to the fact that the left hemisphere is responsible for the right side of the body.
Experiments of Sperry
Split-brain studies have also shown that people with right hemisphere damage have very poor spatial orientation. Often such patients cannot find their way to the house where they have lived for decades before. P. Sperry proved that when the corpus callosum is cut, the following happens: the processes in the two hemispheres of the brain begin to proceed independently. It is like two different people acting independently of each other. According to many scientists, asymmetry is a phenomenon that a person has inherited in the course of evolution and is its acquisition.
Agnosia due to brain damage
Asymmetry of the brain actually manifests itself most clearly with damage to one of the hemispheres. For example, injuries to the right hemisphere can lead to various types of so-called agnosias. With this disorder, a person is not able to perceive previously familiar information. For example, facial agnosia is known, in which the patient does not recognize the faces of familiar people. And this despite the fact that the memory for other objects of the surrounding world and the situation remains absolutely intact.
Twomindset
So, the asymmetry of the brain involves the division of mental functions into two large areas - spatial-figurative thinking and abstract-logical. There are many synonyms for these terms. For example, the definitions of verbal and non-verbal thinking, as well as discrete and simultaneous, are similar. The right hemisphere is responsible for simultaneous thinking, since it perceives an object in the entirety of its properties. The totality of perception is inaccessible to the logically oriented left hemisphere. It analyzes and studies each object separately.
Analysis and synthesis functions
Asymmetry of the brain is responsible for the distribution of functions between the two hemispheres. The left hemisphere is responsible for analytical processing of information. He is characterized by thinking according to the type "from the particular to the general", that is, induction. It processes the entire flow of information from the surrounding world according to a logical principle. The right hemisphere is responsible for such a mental operation as synthesis. In this case, the parts of the perceived object are combined into a whole. Thinking is carried out according to the deductive principle - from the general to the particular. The right hemisphere is responsible for metaphorical, figurative thinking.
Interhemispheric asymmetry: other differences
Perception of current events in chronological order is a function of the left hemisphere. For the right, on the contrary, all events seem to occur simultaneously. It is not oriented in time: for it there is only "here and now". The left hemisphere is oriented toreading diagrams, such as information on maps. The right one, on the contrary, is oriented in a specific space, for example, indoors.
There is also a difference between the distribution of emotion control function in the cerebral hemispheres. The left hemisphere is responsible for positive experiences, the right, on the contrary, for negative ones.
Asymmetry in nature
It should be noted that the phenomenon under consideration is characteristic of many objects of nature. Interhemispheric asymmetry is not only a human prerogative. If symmetry is represented in the structure of molecules and crystals, then asymmetry is in the arrangement of internal organs, the structure of the DNA helix. There is also hair asymmetry.
Research in this area leaves many mysteries. But the progress of science does not stand still. Perhaps the knowledge that now seems obvious will become completely obsolete for scientists of the future. Perhaps the scientists of the future will be able to finally unravel all the secrets of the highest product of evolution - the human brain.
