Cerebellum – structure, functions, diseases and damages

Proven content

The cerebellum is the largest part of the hindbrain (weighs about 150 g) and is located near the brainstem. It precisely coordinates skilled free movements, controlling the strength, duration and strength of muscle contraction, so that these movements are smooth, balanced and accurate. It is also responsible for maintaining balance, muscle tone and body posture. Cerebellar dysfunction, along with degenerative diseases of the cerebellum such as spinocerebellar ataxia, multiple sclerosis, malignancies, etc., can lead to imbalance, hypotension, difficulty speaking, sleeping, maintaining muscle coordination and dyssynergies, which can sometimes be life threatening.

Cerebellum – what is it?

The cerebellum, meaning “small brain” in Latin, is the structure of the hindbrain that controls balance, coordination, movement and motor skills and is believed to be important in processing certain types of memory.

Although the cerebellum only makes up 10% of the brain’s total mass, it contains more than half of the nerve cells than the rest of the brain combined. The cerebellum is also one of the few structures in the mammalian brain where neurogenesis (development of new neurons) has been confirmed.

The cerebellum is the older part of the brain that also occurs in animals. According to scientists, the cerebellum was present in animals that existed before humans.

See also: CNS – structure and functions

Cerebellum – structure

The cerebellum is the largest structure in the hindbrain and is located in the back of the skull below the temporal and occipital lobes, behind the brainstem.

When looking at the brain, the cerebellum looks like a smaller structure separate from the brain, located under the hemispheres of the cerebral cortex. The cerebellum consists of the cortex covering the white matter (in which the nuclei of the cerebellum are scattered), as well as a fluid-filled chamber. It is also divided into two hemispheres – left and right. Between them there is a cerebellar worm.

There are 10 lobules on the surface of the cerebellum. They separate the slots from each other. As for the slots, two of them are the most important, i.e. the first and the posterolateral slit. They divide the cerebellum into lobes: anterior, posterior and flocculent-papular.

The cerebellum communicates with other parts of the central nervous system through the so-called branches:

1. upper cerebellar limb: it connects the cerebellum with the interbrain and runs in it both afferent and centrifugal fibers, responsible for the transmission of signals between the cerebellum and the thalamus and the motor cortex;
2. middle limb of the cerebellum: through it, the cerebellum connects with the bridge and this is the way the afferent fibers reach it, which transmit information about motor activities coordinated by the motor cortex of the brain;
3. inferior limb of the cerebellum: It includes both centrifugal and centripetal fibers responsible for communication between the cerebellum and the medulla.

It should be added that the cerebellum is further divided into areas related to the performance of strictly defined functions:

1. vestibular cerebellum: it includes the flocculent-follicular flap and it is connected with the vestibular system which controls the balance;
2. spinal cerebellum: it is formed primarily by the cerebellar worm and is associated with receiving stimuli from the spinal cord;
3. new cerebellum (cortical): it includes the lateral parts of the cerebellar hemispheres and its function is to receive information from the cerebral cortex.

The cerebellum makes up only 10% of the total brain volume, but contains approximately 50% to 80% of the brain’s neurons.

See also: How does chess affect the brain?

Cerebellum – functions

The cerebellum affects a number of functions in our body.

Cerebellum and coordination of any body movements

Movement is a complex process that requires the collaboration of many different muscle groups. It is worth considering how many muscle groups are involved in the process of walking, running, or throwing a ball.

While it is believed that the cerebellum does not initiate movement, this part of the brain helps organize all the activities of the muscle groups involved in that movement, enabling the body to be able to produce smooth, coordinated movement. This includes eye movements and speaking movements.

See also: Disturbances in the position and movement of the eyes

Cerebellum and mental functions

Scientists believe that the cerebellum plays a role in thinking, including language and mood processing, as well as attention, fear responses, and pleasure or reward responses.

Cerebellum and balance and posture

To understand the important role that the cerebellum plays, it can be helpful to look at what happens when the function of this part of the brain is impaired.

For example, drinking alcohol has an immediate effect on the cerebellum and leads to disruptions in coordination and body movements. People who are seriously intoxicated may find that they cannot even walk in a straight line or touch their own nose when asked to do so.

See also: Do you like a drink? You don’t even know what the consequences might be

Cerebellum and motor science

When you learn to perform a new skill, such as riding a bike or throwing a ball, you often go through a process of trial and error. As you fine-tune your motor movements, you eventually become better able to perform the action, and ultimately you can perform the action smoothly. The cerebellum plays a key role in this motor learning process.

See also: Fine motor skills – characteristics, disorders and developing exercises

Damage to the cerebellum

Injury to the cerebellum or its connection to other parts of the nervous system can result from injury, medical conditions, medications, and other factors, including:

1. alcohol use disorders;
2. a brain tumor;
3. head trauma;
4. Pląsawica Huntingtona;
5. infection;
6. lead or mercury poisoning;
7. drugs including benzodiazepines or barbiturates;
8. multiple sclerosis;
9. Parkinson’s disease;
10. stroke.

Cerebellum – diseases

When our cerebellum is damaged, nerve cells break down and die, which can cause:

1. ataxia: loss of control over any movements (e.g., being able to move the body the way we want);
2. cognitive impairment: restriction of conscious mental activity, including thinking, learning, memory, and concentration;
3. dystonia: involuntary muscle contractions that normally work together, keeping a part of the body in an unusual and often painful position;
4. tremor: involuntary, rhythmic muscle contractions that can lead to tremors in the arms, legs, face, head or vocal cords;
5. unsteady gait: walking unsteadily or clumsily (a person with an unstable gait may appear intoxicated even if they are not);
6. vertigo: vertigo due to spinning, rocking or tilting, often associated with problems with balance and often accompanied by nausea, vomiting, headache, or hearing loss;

In addition, researchers are investigating the relationship between cerebellar dysfunction and the following factors:

1. anxiety disorders: a category of disorders, including panic disorder and social anxiety disorder, that are characterized by excessive or irrational anxiety or fear that is disproportionate to the actual risk;
2. autism spectrum disorder: a developmental condition that results in impaired social interaction and communication;
3. dyslexia: a disorder that impedes speech processing and causes problems with reading, writing and spelling;
4. schizophrenia: a psychotic disorder characterized by distorted perceptions, thoughts, emotions, and beliefs that are not related to reality.

What can you do to protect your cerebellum?

Maintaining a healthy and injury-free cerebellum and the rest of the brain is key to physical and emotional health and overall well-being. Here are some tips to keep in mind to keep your brain healthy:

Protect your head: reduce the risk of head injuries by wearing seat belts in the car; Get rid of the dangers of falling from your home, such as loose wires and slippery rugs; Wear a helmet before riding your bike or when you are about to engage in contact sports.

Exercise regularly: Not only is exercise good for overall health, it also helps stimulate blood flow to the brain.

Eat healthily: a healthy diet can benefit all parts of the body. Focus on fresh fruits and vegetables, whole grains, nuts, seeds, fish, and lean meat.

Limit alcohol consumption: drinking too much alcohol can damage the cerebellum. It can also increase your risk of stroke.

Avoid smoking: smoking is associated with many conditions, including high blood pressure and stroke.