What Is Corticospinal Tract?

The corticospinal tract is responsible for controlling primary voluntary movement for the skeletal and cardiac motor systems, including the trunk, limbs, and cranial muscles. It is also the largest spinal tract that involved involuntary muscle movements. Moving muscles within this area include the trunk, hip, and knee. It is essential for maintaining a good posture, locomotion, and balance.

How to Work Corticospinal Tract

The five hundred cranial nerves are controlled by the corticospinal tract and are connected to the cerebral cortex, brain stem, and spinal cord. Nerves exiting the cranial cavity exit via the medulla oblongata decussate and travel to areas of the body through the intervertebral discs. The inner core of these discs is thickly populated with fibrous tissue. Which helps define the internal regions of the spinal column. The inner reaches of the spinal canal are lined with dense glial cells. Which provide structures and nutrients necessary for supporting the back, pelvis, and neck.

Disorders and Diseases Can Affect The Corticospinal Tract

Several disorders and diseases can affect the corticospinal tract and cause impairments in its functions. Among them are multiple sclerosis (MS), stroke, traumatic brain injury, multiple sclerosis-related cerebellar degenerations, central auditory processing disorders, and Parkinson’s disease. These disorders can be the result of genetic differences and environmental factors. Multiple sclerosis is a chronic progressive disorder affecting the central nervous system and causing loss of self-awareness, stiffness of muscles, loss of dexterity, and fatigue. This disorder generates wide-ranging and permanent disabilities in the victim’s daily life. Limiting his or her ability to perform even the simplest activities of daily living.

Parkinson’s disease is a degenerative disorder of the central nervous system which causes the loss of voluntary movements and cognitive dysfunction. It is characterized by rigidity and slowing of the motor pathway in the brain. Causing certain mental signs and symptoms such as rigidity of the trunk, inability to extend the limb, the rigidity of eyes, involuntary twitching of limbs, difficulty in concentrating, and irritability. It is a disorder of the central nervous system which affects the secretion of dopamine, the body’s chemical signal that helps maintain the functioning of the brain and its various parts. Dopamine is essential for proper nerve transmission. Which is important in the movement of both the internal organs and the limbs.

Multiple Sclerosis

Multiple Sclerosis (MS) is a type of degenerative non-degenerative disorder of the central nervous system which results from the destruction of myelin in the corticospinal tract. Myelin is a protective sheath around the nerves. Which helps the nerves conduct impulses smoothly by making sure that they do not pass through the sheath surrounding the nerves. As myelin gets damaged. The integrity of the motor cortex deteriorates leading to loss of muscle coordination, gross motor skills, and independent movement of the limbs. When this happens. The result is impaired voluntary movement. The associated discomfort and impediment in walking, standing, and other activities. The extent of the damage depends on the severity of the disease.

Parkinson’s Disease

MS is closely related to stroke and Parkinson’s disease. Both of which are diseases of the nervous system that lead to loss of voluntary control. MS is also related to severe brain trauma. Which further compromises the ability of the patient to regulate his/her own movements. MS occurs in five percent of all cases of Parkinson’s disease and approximately 25 percent of cases of stroke. With respect to symptoms, MS is characterized by poor muscle tone. Wasting of muscle mass with the formation of age spots. Stiffness of the spinal cord, loss of balance and coordination, difficulty in swallowing food, decreased sense of smell, and reduced facial expression.

Also Read: Inferior Mesenteric Artery

Types of Multiple Sclerosis (MS)

·         Primary

There are two types of MS: primary and secondary. In primary MS, the myelin in the central cortex is continually damaged and leads to a loss of neurological function. The disease often begins at the age of twenty years but it can affect anyone regardless of age. MS is caused by abnormal myelin production by the cells and synapses in the cerebral cortex. Leading to the death of the myelin-producing neurons.

·         Secondary

In secondary MS, the myelin is regenerated. But the process does not last. As a result of this. Neurons are still lost. Do not perform their usual functions. These neurons provide inputs to the motor neurons (ie: thigh, arm, shoulder, and face muscles). The person receives movement directions. This form of MS is called predominantly motor neurons MS.