Split brain is normal. Andrey Kurpatov on QWERTY / brain, science, man
The hemispheres of our brain are connected by a powerful plexus of nerve fibers called the corpus callosum. In addition to it, there are several more points of contact, but the corpus callosum is the most powerful “bridge” between the right and left hemispheres, which allows them to exchange information with each other.
In the classification of living beings, man is given the honorary name – homo sapiens. It is natural to assume that our mind is conditioned by a special device of the brain. What does it consist of? The human brain is large and weighs a lot. But there are animals in which the brain is larger and heavier.
Humans have a large relative brain weight, that is, the ratio of brain weight to a kilogram of total body weight. But in these respects we are inferior to animals – cetaceans are in the lead in terms of the relative weight of the brain. For a very long time, scientists believed that humans have the largest surface of the cerebral cortex, that it has more convolutions, that it contains more nerve cells, that nerve cells are denser in it. But it turned out that animals with a legendary reputation – dolphins – surpassed us in these indicators as well.
If not the size and weight of the brain, then what is the distinguishing feature of the brain of a “smart person”? Today we can point to only one unique feature of our brain – functional asymmetry. The brain of all animals and the human brain is symmetrical – its right and left halves are built identically both in terms of composition and number of individual elements, and in general architecture. In animals, the right and left halves of the brain perform the same work.
In humans, the right and left hemispheres of the brain have different functions, they control different types of activities. It has been known since ancient times that with focal lesions of the cortex (due to hemorrhages, injuries, tumors, etc.), complete or partial loss of speech can occur – aphasia. However, it was only a little over a hundred years ago that it was proven that aphasia develops only with lesions of the left hemisphere.