What Makes Human Brain unique Yale study sheds light on the genetic changes

 

The human brain is unique in several ways, including its size, structure, and function.

Size: The human brain is the largest brain relative to body size of any animal. It is about three times larger than the brain of a chimpanzee, our closest living relative.

Structure: The human brain has a highly developed cerebral cortex, the outermost layer of the brain. The cerebral cortex is responsible for higher-level cognitive functions such as language, reasoning, and problem-solving.

               

Function: The human brain is capable of a wide range of complex cognitive functions, including language, abstract thought, and problem-solving. These abilities are due to the unique structure and function of the human brain.

In addition to these general features, there are also a number of specific features that make the human brain unique. For example, humans have a larger number of neurons in the prefrontal cortex, the area of the brain responsible for planning and decision-making. Humans also have a more developed language system than other animals.

                 

The unique features of the human brain are what make us human. They allow us to think, reason, and communicate in ways that no other animal can.

A Yale study, published in the journal Cell, provides a fuller picture of the genetic changes that shaped the evolution of the human brain, and how the process differed from the evolution of chimpanzees.

The study focused on a class of genetic switches known as Human Accelerated Regions (HARs), which regulate when, where, and at what level genes are expressed during evolution.

               

Using advanced techniques, researchers were able to track how HARs interact with genes and human neural stem cells, which allowed them to identify gene targets for nearly all HARs — a significant advance in the study of human evolution.

The results reveal that HARs largely regulate the same genes in both species, particularly those involved in brain development. However, HARs adjust gene expression levels differently in humans, suggesting that evolutionary changes to brain function emerged not by reinventing genetic pathways but by modifying their output.

               

Many HAR gene targets are active in the developing human brain and are linked to processes such as formation of neurons and maintaining communication between neurons. Some are also associated with conditions like autism and schizophrenia, highlighting the potential role of HARs both in shaping normal brain function as well as neurological disorders.