Human Brains’ Plasticity Contributes to Evolution

But as smart as chimps are, their brain power pales in comparison with our own.

Researchers from George Washington University developed three-dimensional models of humans and chimps brain and compared them with each other.

The neocortex-the outermost layer of the brain characterized by the squiggly sulci, or brain folds-is the region that gives all primates their exceptional intelligence.

After carrying out a series of MRI scans, researchers were able to create 3-D models of each brain, in order to study it more carefully.

You may have heard that brains, in general, are plastic. Chimps demonstrate plasticity when they pick up things like cooperative grooming practices. The study found that human and chimpanzee brain size were both greatly influenced by genetics.

The study suggested there are many factors that make brain of humans superior to that of chimpanzees.

Specifically, researchers looked at the correlations between genetics and brain size and structure among relatives. The team wanted to see if there is a direct link between brain size, genetical background and anatomical structure.

More precisely, the human brains had belonged to twins and other siblings, while the animal brains had also originated from closely related individuals, such as half siblings or parents and offspring.

Now, this study has shown a new manner in which the two separate groups are distinct, and this is related to the way their brain’s architecture is shaped.

In chimpanzees, brain organisation is also highly inherited, but in humans this is not the case. This means that chimps have greater limitations on the ways in which their brains can develop and on their capacity to learn new behaviors or skills compared with humans. In contrast, the findings related to brain organisation revealed key differences between chimpanzees and humans. This allows the environment, experience, and social interactions with other individuals to play a more dramatic role in organizing the cerebral cortex.

Aida Gómez-Robles, an anthropologist from the George Washington University and lead author of the study, said, “We found that the anatomy of the chimpanzee brain is more strongly controlled by genes than that of human brains, suggesting the human brain is extensively shaped by its environment no matter its genetics”.

According to their findings, it would seem that the human brain possesses a higher degree of plasticity, meaning that the human brain is very malleable and it is capable of responding and adapting to any number of environmental changes. Relatives with similar genes tended to have very similarly sized brains.

In the context of neurology, plasticity describes the tendency of the brain to change shape, structure and size in reaction to external factors.