Where is the gray matter of the cerebrum located?

Overview

The brain is composed of more than a thousand billion neurons. Specific groups of them, working in concert, provide us with the capacity to reason, to experience feelings, and to understand the world. They also give us the capacity to remember numerous pieces of information.

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Where is most of the gray matter located?
Where is gray matter found in the brain quizlet?
How is grey and white matter arranged in the cerebrum?
Where is gray and white matter located?

There are three major components of the brain. The cerebrum is the largest component, extending across the top of the head down to ear level. The cerebellum is smaller than the cerebrum and located underneath it, behind the ears toward the back of the head. The brain stem is the smallest and is located under the cerebellum, extending downward and back toward the neck.

The cerebral cortex is the outside portion of the cerebrum, also called the “gray matter”. It generates the most complex intellectual thoughts and controls body movement. The cerebrum is divided into left and right sides, which communicate with each other through a thin stalk of nerve fibers. The grooves and folds increase the cerebrum’s surface area, allowing us to have a tremendous amount of gray matter inside of the skull.

The left side of the brain controls the muscles on the right side of the body and vice versa. Here, the left side of the brain is highlighted to show the control over right arm and leg movement, and the right side of the brain is highlighted to show the control over left arm and leg movement.

Voluntary body movements are controlled by a region of the frontal lobe. The frontal lobe is also where we shape emotional reactions and expressions

There are two parietal lobes, one on each side of the brain. The parietal lobes are located behind the frontal lobe towards the back of the head and above the ears. The taste center is located in the parietal lobes.

All sounds are processed in the temporal lobe. They are also important for learning, memory, and emotion. The occipital lobe is located at the back of the head behind the parietal and temporal lobes.

The occipital lobe analyzes visual information from the retina and then processes that information. If the occipital lobe becomes damaged, a person could become blind, even if his or her eyes continue to function normally

The cerebellum is located at the back of the head underneath the occipital and temporal lobes. The cerebellum creates automatic programs so we can make complex movements without thinking.

The brain stem is located underneath the temporal lobes and extended down to the spinal cord. It is critical for survival because it connects the brain with the spinal cord. The top portion of the brainstem is called the midbrain. The midbrain is a small portion of the brain stem located at the top of the brain stem. Just below the midbrain is the pons, and below the pons is the medulla. The medulla is the part of the brain stem closest to the spinal cord. The medulla, with its critical functions, lies deep within the head, where it is well-protected from injuries by an extra-thick section of overlying skull. When we are asleep or unconscious, our heart rate, breathing and blood pressure continue to function because they’re regulated by the medulla.

And that concludes a general overview of the components of the brain.

At the rear of the brain is the cerebellum. The cerebellum is similar to the cerebrum in that each has hemispheres that control the opposite side of the body and are covered by gray matter and surface folds. The vermis, which is a central constricted area, connects the hemispheres.

The cerebellum is concerned with the automatic regulation of movement and posture, and the learning of new motor patterns. The cerebellum basically coordinates body movement and is located at the back of the brain beneath the occipital lobes.

The cerebellum fine tunes motor activity or movement such as the fine movements of fingers. The cerebellum controls balance or equilibrium, posture, and coordination by controlling the tone of muscles and the position of limbs. The cerebellum is important in one's ability to perform rapid and repetitive actions such as playing a video game. In the cerebellum, right-sided abnormalities produce symptoms on the same side of the body.

The cerebellum functions closely with the cerebral cortex and the brain stem. It's separated from the cerebrum by the fold of dura called the tentorium. It's divided into two lateral lobes connected by a fingerlike bundle of white fibers called vermis. The outer layer of the cerebellum consists of fine folds called folia. Three fiber bundles called cerebellar peduncles connect the cerebellum to the three parts of the brain stem: The midbrain, the pons, and the medulla oblongata.

Damage to the cerebellum or the cerebellar peduncles is very common in multiple sclerosis (MS) due to the large amount of white matter in these structures.

Some of symptoms associated with damage to the cerebellum or the nervous tracts leading to it are:

•	Dysdiadokokinesia (difficulty in performing rapid alternating movements)
•	Ataxia (difficulty in coordinating movements)
•	Tremors
•	Loss of balance and vertigo
•	Muscle weakness
•	Dysarthria (loss of coordination of the muscles controlling speech)
•	Loss of postural tone

The white matter regions of the central nervous system (CNS) contrast with the gray matter regions. The white matter refers to those parts of the brain and spinal cord that are responsible for communication between the various gray matter regions and between the gray matter and the rest of the body. In essence, the gray matter is where the processing is done and the white matter is the channels of communication.

The white matter is so-called because it contains many nerve fibers or neurons that are sheathed in the white fatty insulating protein called myelin. In section, myelin is white whereas the gray matter is that color due to all the gray nuclei contained in the cells that make it up.

The white matter is found in the inner layer of the cortex, the optic nerves, the central and lower areas of the brain or brainstem, and surrounding the central shaft of gray matter in the spinal cord.

MS is predominantly a disease of the white matter in the CNS. About 95% of all lesions associated with MS occur in the white matter.

The gray matter regions of the CNS, the brain and spinal cord, contrast with the white matter regions. The gray matter is the areas where the actual "processing" is done whereas the white matter provides the communication between different gray matter areas and between the gray matter and the rest of the body.

The neurons in the gray matter consist of neuronal cell bodies and their dendrites. The dendrites are short protrusions that communicate with immediately neighboring neurons in the CNS. In contrast with the neurons of the white matter, gray matter neurons don't contain long axons that transmit the nerve impulses to more distant regions of the CNS.

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About 40% of the human brain is made up of gray matter and the other 60% is white matter. The gray matter, however, consumes about 94% of the total oxygen used by the brain.

The vast majority of MS lesions occur in the white matter areas but a small number, about 5%, do occur within the gray matter. Gray matter is so-called because in section it has a gray color due to all the gray nuclei in the cells that make it up.

Gray matter involvement is detected even in the earliest stages of MS, and gray matter atrophy occurs at a faster rate than white matter atrophy early in the disease course.

Studies have determined that:

•	Gray matter involvement and in particular cortical demyelination can be extensive in MS.
•	Gray matter pathology may occur in part independently of white matter lesion formation.
•	A primarily gray matter-related process may be the earliest manifestation of MS.
•	Gray matter involvement is associated with physical disability, fatigue, and cognitive impairment in MS.
•	Gray matter disease might help explain the observed dissociation between markers of inflammatory demyelination (relapses, white matter gadolinium enhancement, white matter lesion burden) and disease progression.

It's likely that gray matter damage is related to white matter damage. However, continued studies of gray matter pathology as well as neuronal and axonal involvement in MS and related experimental models are necessary to better understand the etiology and pathogenesis of the degenerative components.

In a recent supplement to Neurology, it was stated basically that recent studies have found that gray matter damage, which isn't effectively detected through MRI, may be more pronounced than white matter damage, especially early in the disease process, and can have considerable impact on clinico-cognitive functioning and neuro-psychological deficits. So gray matter damage is probably greater than earlier believed or seen on an MRI and because of this finding, it's felt that cognitive and psychological functions may have been impacted to a greater extent.

Where is most of the gray matter located?

Grey matter is abundant in the cerebrum, cerebellum, brain stem, and the spinal cord. The sheet of grey matter that constitutes the cerebrum varies in thickness from about 2 to 5mm. In the cerebellum, which makes up just 10% of the brain's volume, contains more neuronal cell bodies than the rest of the brain combined.

Where is gray matter found in the brain quizlet?

-The gray matter, containing neuron cell bodies and dendrites, is found in the cortex (surface layer) of the brain and deeper within the brain in aggregations known as nuclei (superficial).

How is grey and white matter arranged in the cerebrum?

White matter is found buried in the inner layer of the brain's cortex, while the grey matter is mainly located on the surface of the brain. The spinal cord is arranged in the opposite way, with grey matter found deep inside its core and the insulating white matter wrapped around the outside.

Where is gray and white matter located?

The white matter is found in the inner layer of the cortex, the optic nerves, the central and lower areas of the brain or brainstem, and surrounding the central shaft of gray matter in the spinal cord. MS is predominantly a disease of the white matter in the CNS.