Why does the human brain stack up like this

  Speaking of the human brain, you must be able to think of this kind of nuts-walnuts. Their appearance is too similar, with layers of folds and deep and shallow grooves. It is no wonder that it advocates “complementing shape with shape”. Of Chinese people think that “walnuts can nourish the brain”. But in fact the two are not the same.
  If you compare several walnuts, you will find that the sulcus of walnuts is different. They look different, but the brain is not. Scientists have found that people’s brains are very similar, with a lot of grooves in some places, and relatively smooth in some places. It seems that the brain also has a “fixed drawing”. If someone’s brain does not fold according to the “drawing”, they are likely to be sick.
The “drawings” of the brain folding

  In the history of biological development, the nervous system is an important evolution. We believe that the more complex the nervous system is, the higher its evolutionary level. Except for a handful of animals, such as sponges, almost all animals in the eukaryotic phylum have a nervous system. Mammals not only have a nerve center-the brain, but also have evolved a cerebral cortex that can think. But the human cerebral cortex is still very special. The brains of other animals are not folded into “walnuts” like ours. Even the close relatives of human apes are not as “wrinkled” as our brains. Why is our cortex especially “wrinkled”? What determines it? What is the “blueprint” of the brain?
  Needless to say, the “blueprint” of the brain is the genes, which instruct the brain to fold in fixed steps, and there are different genes involved in the folding of the brain. Researchers at the Max Planck Institute in Germany have discovered a gene that exists only in humans. This gene named “ARHGAP11B” allows the human brain to produce more brain cells. When there are more and more brain cells and the brain cannot fit, folding will occur.

  Then, other genes guide the brain to fold step by step. For example, researchers at the Max Planck Institute in Germany and the Leibniz Institute for Polymers in Germany found that the brain always starts with brain cells that have three proteins: proteoglycan connexin, basement membrane glycan and collagen. Folding, the genes that control the synthesis of these three proteins mark the starting point of folding.
  Adam O’Neill, a neurologist at the University of Otago in New Zealand, found another gene, PLEKHG6, which can direct brain cells to produce at the right time and go to the right place. O’Neill modified a skin cell in the laboratory. It should have developed into the skin of the hand. By changing the gene expression of this cell, it will develop into a “mini brain”. Then, O’Neill disabled the PLEKHG6 gene and found that some brain cells in the “mini brain” did not reach the correct position, and the final folded “mini brain” was not the same as the normal brain.
  So we know that the production sequence and location of brain cells also have a “blueprint”. The brain cells must obey the instructions and reach the correct position, so that when the brain folds according to the “first production, first folding” rule, it will fold. The correct shape.
Serious consequences of folding errors

  The genes that control brain cells in normal people are similar, so the production order and location of brain cells can be kept consistent, so that the folded shape of the brain of different people will be very similar, but if the gene is mutated, the folded shape of the brain will change , The possibility of mental illness will greatly increase.
  Schizophrenia is a relatively common mental illness, manifested by mental disorders, delusions, and perceptual distortions, but many other mental illnesses also have these symptoms, so it is difficult to confirm whether a patient really has schizophrenia based on these symptoms. And the sooner a patient with schizophrenia receives psychotherapy or medication, the faster his condition will get better. Therefore, if there is a way to diagnose schizophrenia earlier, it will greatly increase the possibility of curing the disease.
  For this reason, many scientists have conducted research in this area. Lina Parañapan, an associate professor of psychiatry at the University of Western Ontario in Canada, found that an MRI scan of the brain to compare the shape of the folds of the brain is conducive to the diagnosis of schizophrenia. The research team collected MRI scan data of 123 test subjects in Switzerland, including 79 potential patients who had shown symptoms of schizophrenia but had not yet been diagnosed and 44 healthy people. They found that their brains were folded in different shapes. Normal people have more folds in the brain area, but potential patients have few folds. The cerebral cortex is very flat, while the adjacent areas are the opposite. Four years later, 16 of the 79 potential patients who participated in the experiment were diagnosed with schizophrenia. If potential patients could be prevented based on the physical examination results of abnormal brain fold shapes 4 years ago, they would probably not have the disease.
  The number of brain cells in our cerebral cortex is far more than other mammals. This is the reason why our intelligence has soared. At the same time, the increased number of brain cells and complex brain structures also increase our mental illness. risk. On the basis of understanding the brain structure, early prevention and early treatment should become an important means for us to deal with risks.