Scientists reveal human brains differ from apes’ much more than previously believed
The researchers analyzed the activity of genes in various layers of the medial prefrontal cortex of humans, chimpanzees, and macaques, - TASS
An international research team from Russia, China, and Germany has uncovered differences in the structure of the cerebral cortex of the brains of humans and chimpanzees, which are more significant than had been previously assumed, Skoltech’s press service said. The results of the study have been published in the Nature Neuroscience. According to the announcement, the microarchitecture of the human brain’s cerebral cortex underwent notable changes during the course of evolution, despite the seemingly close anatomical similarities of human and ape brains.
The scientists studied the cerebral cortex, the domain of the brain which developed most significantly during the evolutionary process. Each of the six layers of the brain’s cortex has its functional role in handling information, the particular distribution of various types of cells and the organization of a cell network, as well as different gene functions. Taking laboratory rodents as a test case, it has been shown that the work of more than 5,000 genes is different for various layers of the cortex. As far as the human brain is concerned, no systematic analysis of gene functioning in the different layers of the brain’s cortex has ever been done before.
The researchers analyzed the activity of genes in various layers of the medial prefrontal cortex of humans, chimpanzees, and macaques. As a result, they detected 2,320 genes, the new markers of the layers of the cortex, which are unique for humans, while the 367 genes which are common for humans and chimpanzees function in the cortex’s other layer. When comparing chimpanzees to macaques, only 133 genes have such differences.
Interestingly, from the evolutional divisions between branches of macaques and chimpanzees, a greater amount of time had elapsed than between the partition of chimpanzees and humans, but the changes are less pronounced for the first case. This implies that the prefrontal cortex has notably changed throughout the course of man’s evolution.
The scientists believe that the results of the study will present new data on the peculiarities of the microarchitecture and functioning of genes in the tissues of the human brain, and will offer the opportunity for developing new techniques of regulating human cognitive functions at the regular aging rates and at the pathogenic mechanisms in the cerebrum