Some of the work i have done

The Cerebellum

Name

Institution

The Cerebellum

Functions of the Cerebellum

The cerebellum is also known as the “little brain” which is found or located at the back of the brain. It underlies the temporal and occipital lobes. Although this part of the brain contains over fifty percent of the neurons held in the brain, it only accounts for ten percent volume of the brain. The cerebellum has been historically known as a motor structure; however it does not initiate motor functions; rather it modifies the commands given by the descending pathways. This helps to make the movements’ to be more accurate and adaptive (Knierim, 2014).

The cerebellum has the following functions.

a. The cerebellum plays an important function in making adjustments to posture to ensure or maintain balance. It receives input from proprioceptors and vestibular receptors and modulates the commands to the motor neurons so as to compensate for the changes upon muscles due to load and shifts in the position of the body. What this does is to help maintain posture and balance.

b. The cerebellum also plays a key role in coordinating voluntary movements. Movements in the human body occur when different muscle groups act together in a temporally coordinated function. Amongst its main functions is to ensure coordination in the force and timing of these muscle groups so as to produce or have fluid body or limb movements’.

c. The cerebellum also plays a key role in motor learning, for example, learning to swing a baseball bat to hit baseball. It fine tunes and adapts motor programs to increase accuracy through a process of trial and error.

d. Finally, the cerebellum also plays a key role in certain aspects of cognitive functions like language. This means that though well known for its motor functions; the cerebellum has other functions that have not yet been exhaustively understood.

Disorders of the Cerebellum

Damage to the cerebellum is characterized by motor disturbances. This is because the cerebellum plays a vital role in motor coordination. Below is a number of disorders that affect the cerebellum.

a. Cerebellar ataxia: - there are two forms of this disorder the first is when a patient experiences disturbances in gait or posture. The patient suffers from lesions in the vestibulocerebellum that causes the patient to have abnormal gait that may resemble an inebriated individual. The reason for a patient having a wide gait is so that he can maintain balance when he stands still. The second form of this disorder is when a patient is unable to coordinate an activity and its timing of the different muscle groups. Instead patients suffering from this condition perform such activities in turn and are unable to do the same together at once.

b. Dysdiadochokinesia: - the patient is unable to perform movements’ alternately such as supinating and pronating the forearms and hands. For example turning the palms of both hands together. A Patient suffering from this disorder will be able to turn each palm individually and not together in coordination.

c. Dysmetria: - this refers to when a patient is unable to gauge the force and distance of objects. For example, when reaching out for a cup a patient with this condition may knock it over as he is unable to gauge correctly the correct force to use.

d. Hypotonia: - this is when a patient has decreased muscular resistance that causes the limbs of the patient to swing back and forth after the original reflex contraction.

e. Scanning speech: - this is when a patient has disjointed, and slow speech as the patient with this condition has difficulty coordinating the tongue, jaw, and larynx muscles. As the cerebellum that coordinates motor functions assists this group of muscles to work together.

f. Delay or lapse in initiating movements: - cerebellar patients find it challenging to initiate movements that are effortless to normal individuals.

g. Nystagmus: - this is when a patient’s eyes continuously oscillate due to damage of the vestibulocerebellum. The cerebellum fine tunes the vestibulocochlear response and damage to it leads to this condition.

h. Intention tremor: - this is when a patient suffers from an oscillatory movement. For example, when trying to press a button the hand may oscillate as it nears the button (Fredericks & Saladin, 1996)..

The reason for my interest in the cerebellum is because despite its small size in terms of volume in the brain it contains a large percentage of neurons.

References

Knierim, J. (2014). Overview: Functions of the Cerebellum. Retrieved from http://neuroscience.uth.tmc.edu/s3/chapter05.html

Fredericks, M, C., & Saladin K, L. (1996). Pathophysiology of the Motor Systems: Principles and Clinical Presentations. Disorders of the Cerebellum and Its Connections. FA Davis.

.