Introduction[edit | edit source] Show
The cerebellum is a vital component in the human brain as it plays a role in motor movement regulation and balance control. The cerebellum [1] (see image on R, horizontal fissure marked red)
Damage to this area in humans results in a loss in the ability to control fine movements, maintain posture, and motor learning The cerebellum is neuron-rich, containing 80% of the brain’s neurones organized in a dense cellular layer, and it's surface area when unfolded is nearly 75% of the surface area of the cerebrum.[1] Anatomical Position[edit | edit source]The cerebellum is located at the back of the brain, immediately inferior to the occipital and temporal lobes, and within the posterior cranial fossa. It is separated from these lobes by the tentorium cerebelli, a tough layer of dura mater. It lies at the same level of and posterior to the pons, from which it is separated by the fourth ventricle. Structure[edit | edit source]The cerebellum consists of two hemispheres which are connected by the vermis, a narrow midline area. The cerebellum consists of grey matter and white matter:[2]
There are three ways that the cerebellum can be subdivided – anatomical lobes, zones and functional division[2]
Nerves[edit | edit source]The cerebellum attaches to the brainstem by three groups of nerve fibers called the superior, middle and inferior cerebellar peduncles, through which efferent and afferent fibers pass to connect with the rest of the nervous system. Function[edit | edit source]Function by regions
Main Functions overall[3]
Blood Supply[edit | edit source]The cerebellum receives its blood supply from three paired arteries (originate from the vertebrobasilar anterior system)[2]
The SCA and AICA are branches of the basilar artery, which wraps around the anterior aspect of the pons before reaching the cerebellum. The PICA is a branch of the vertebral artery. Venous drainage of the cerebellum is by the superior and inferior cerebellar veins. They drain into the superior petrosal, transverse and straight dural venous sinuses. Clinical Significance[edit | edit source]The cerebellum receives afferent information about voluntary muscle movements from the cerebral cortex and from the muscles, tendons, and joints. It also receives information concerning balance from the vestibular nuclei. Each cerebellar hemisphere controls the same side of the body, thus if damaged the symptoms will occur ipsilaterally.[1] Dysfunction of the cerebellum can produce a wide range of symptoms and signs. The most common cause of cerebellar dysfunction is alcohol poisoning, but also trauma, multiple sclerosis, tumors, thrombosis of the cerebellar arteries and stroke.[1] The clinical picture depends on the functional area of the cerebellum that is affected[3].
A wide variety of manifestations are possible (remembered by acronym ‘DANISH‘)[2]
Occlusion of PICA cause Wallenberg syndrome The short video below gives a good picture of the manifestations of cerebellum damage [4] The cerebellum appears to play a role in many types of behaviours. Cerebellar damage not only affects movement coordination but also disrupts some perceptual abilities such as visual motion discrimination. The cerebellum acts to make predictions for different cerebral areas of the brain to optimize their abilities-- helping to predict optimal motor commands for movement control and upcoming sensory events for sensory perception possibly explaining how cerebellar damage affects other behaviours.[5] Physiotherapy[edit | edit source]Physical therapy intervention is the primary treatment for gait ataxia and imbalance in individuals with cerebellar damage. Physical therapy aims to restore movement and function following cerebellum injury using movement, exercise and manual therapy, as well as education and advice. Physical therapy may include exercises such as
An important finding of a recent study[7] was that the level of challenge to balance was more important than the duration of exercise in producing Neurorehabilitation and neural repair. Cerebellar patients with ataxia can benefit from a home exercise program focused on balance training (with significant improvements after just six weeks). Highlighted was the importance of the 1. level of challenge to balance being of upmost importance 2. individualizing the program and offering continued training and progression if necessary to see effect retention. Regeneration ? ![edit | edit source]Current research is going on into the search for neurogenesis of the central nervous system. An exciting prospect. Some of the news is reported below.
Further Viewing[edit | edit source]The below 4-minute video gives a great 3D view of the cerebellum and highlights it's similar structure to that of the cerebrum. [10] References[edit | edit source]
What part of the nervous system is responsible for mediating reflexes?The area of the nervous system that is responsible for mediating reflexes is the: ANS: spinal cord. The spinal cord is the main highway for ascending and descending fiber tracts that connect the brain to the spinal nerves, and it mediates reflexes.
Which of the following would the nurse use to test the motor coordination of an 11 month old infant?Which of these tests would the nurse use to check the motor coordination of an 11-month-old infant? To screen gross and fine motor coordination, the nurse should use the Denver II with its age-specific developmental milestones.
Which nervous system brings back information from muscles and glands?The autonomic nervous system is the part of the nervous system concerned with the innervation of involuntary structures, such as the heart, smooth muscle, and glands within the body.
Which nervous system includes the spinal cord?The nervous system has two main parts: The central nervous system is made up of the brain and spinal cord. The peripheral nervous system is made up of nerves that branch off from the spinal cord and extend to all parts of the body.
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