Gray Matter – Concept, functions, location and importance

We explain what gray matter is, what its functions are and where it is located. Also, why is it important and what is white matter.

Gray matter - brain
In the brain, gray matter spreads to form the cerebral cortex.

What is gray matter?

It is known as gray matter or gray matter to the element that constitutes certain areas of the central nervous system (brain and spinal cord) of characteristic gray color, composed of neuronal bodies (the “body” of neurons) and dendrites devoid of myelin, together with glial cells or neuroglia.

Gray matter found inside the spinal cord, tending towards the center and towards its sides, in the form of the letter H; and in the brain, on the other hand, in the external zone except in the basal ganglia, thus forming the cerebral cortex: the most complex nervous structure in the human body.

In principle, not being covered by myelin, the gray matter not used for the rapid transmission of nerve impulsesTherefore, it is associated with other intellectual capacities of the human being, although it is not possible to affirm that the greater the mass of gray matter, the greater the intelligence, since dolphins have more than human beings.

Gray matter function

Gray matter - neurons
Through neural connections, gray matter fulfills mental and cognitive functions.

The gray matter of the brain fulfills the vital function of being the receiver of the information and the person in charge of the thought, that is, of reasoning and memory in its various areas and meanings. From linguistic ability, perception, interpretation, abstraction and a huge etcetera of mental and cognitive functions, they all depend on gray matter and the connections between its multiple types of neurons.

Instead, in the spinal column, gray matter operates as regulating and selecting the information that will be transmitted to the brain, but also from a source of immediate impulses and the so-called “body memory” that allows all reactions not to come from the brain and thus lightens the work of nervous processing.

Location of gray matter

Gray matter is found on the entire brain surface, as it makes up the cortex of the brain, the most developed, complex and most connected area of ​​our entire nervous system. It is also found in the basal ganglia, deep in the cerebellum, and in the areas of the thalamus and hypothalamus.

At the same time, can be found inside the spinal cord, in an H- or butterfly-shaped segment, on the dorsal, intermediolateral and ventral horns of the spine, as well as in the intermediate zone (dorsal nucleus of Clarke).

Importance of gray matter

Gray matter
Thanks to gray matter, complex, creative and abstract thought patterns emerged.

Medical cases of people injured in regions of the brain rich in gray matter have been seen, and the impact that these injuries can and usually have on various areas of human cognitive functioning: language ability, short or long-term memory, has been noted. , associative ability, learning, etc.

Thanks to this, it is known that gray matter is precisely the portion of the nervous system that allowed the emergence of complex thought patternscreative and abstract in primitive humanity. So it was not enough to have a larger brain to have human intelligence, but rather a brain with abundant gray matter and a rough cortex was required, which fosters numerous connections between the neurons that compose it.

Gray matter and white matter

Gray matter differs from white matter in much more than its color, determined by the high presence of dendrites with myelin in the latter (myelin is whitish in color). They are distinguished in the speed of transmission of nervous information, much faster in white matter that in the gray, and in the depth to which it is, since the white matter is the interior of the brain (although the covering of the spinal cord).

White matter was long thought to be passive, but today we know that plays a vital role in the distribution of nervous information and in the modulation of action potentials, that is, it is responsible for basic operational functions that support complex processing, which is responsible for gray matter, especially in the brain.