Crebellum Essay

The Cerebellum

The cerebellum (or ‘Little Brain’) is an area located at the back of the brain, positioned underneath the occipital and temporal lobes [Figure 1]. The structure’s main purpose is the fine-tuning of movement, and maintaining posture and balance. The cerebellum is commonly thought of as a motor system, because it is mostly involved in outputting to the movement (motor) system. However, the cerebellum’s purpose is not the creation of motor commands, rather the moderation and adaptation of commands to increase their accuracy. It also uses a surprisingly large amount of neurons relative to its size: although it is only approximately 10% of the brain’s total volume, it accounts for over 50% of the total number of neurons in the brain .

The main functions of the cerebellum are thus:

• Coordination of voluntary movement

• Maintenance of balance and posture

• Motor learning

• Cognitive functions

Each of these I will now explain in more detail.

Coordination of voluntary movement:

The cerebellum helps to control and fine tune the movements we choose to make on a daily basis. For this reason, people with damage to the cerebellum will experience difficulty moving about, and will experience a lack of movement coordination. This is because most movements are created my different muscle groups moving together in a precise, coordinated way, and one of the main functions of the cerebellum is to control the timing of these movements, and the force with which they should be applied. With cerebellar damage, the brain can no longer do this, and movement becomes erratic and jerky.

Maintenance of balance and posture:

One of the most important functions of the cerebellum is the maintenance of balance and posture. The cerebellum receive...

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