The cerebellum is a part of the brain that plays a vital role in virtually all physical movement.
This part of the brain helps a person drive, throw a ball, or walk across the room. The cerebellum also assists people with eye movement and vision.
Problems with the cerebellum are rare and mostly involve movement and coordination difficulties.
This article explains the anatomy, functions, and possible disorders of the cerebellum. It will also offer tips on preserving brain health.
The brain is hugely complex, but is, on a basic level, divided into the cerebrum, brainstem, and cerebellum.
The cerebrum participates in the higher levels of thinking and action. Four lobes or sections make up the cerebrum, and each performs a different job.
Four brain lobes
The frontal lobe sits at the front and top of the brain. It is responsible for the highest levels of human thinking and behavior, such as planning, judgment, decision making, impulse control, and attention.
The parietal lobe lies behind the frontal lobe. This lobe takes in sensory information and helps an individual understand their position in their environment.
The temporal lobe is at the lower front of the brain. This lobe has strong links with visual memory, language, and emotion.
Finally, the occipital lobe is located at the back of the brain. The occipital lobe processes visual input from the eyes.
Brainstem and cerebellum
The cerebellum and brainstem accompany the cerebrum in promoting full physical and mental function.
The brainstem manages vital automatic functions, such as breathing, circulation, sleeping, digestion, and swallowing. These are the involuntary processes controlled by the autonomic nervous system.
The brainstem also controls reflexes.
The cerebellum is the area at the back and bottom of the brain, behind the brainstem. The cerebellum has several functions relating to movement and coordination, including:
- Maintaining balance: The cerebellum has special sensors that detect shifts in balance and movement. It sends signals for the body to adjust and move.
- Coordinating movement: Most body movements require the coordination of multiple muscle groups. The cerebellum times muscle actions so that the body can move smoothly.
- Vision: The cerebellum coordinates eye movements.
- Motor learning: The cerebellum helps the body to learn movements that require practice and fine-tuning. For example, the cerebellum plays a role in learning to ride a bicycle or play a musical instrument.
- Other functions: Researchers believe the cerebellum has some role in thinking, including processing language and mood. However, findings on these functions are yet to receive full exploration.
As a result of the close relationship between the cerebellum and movement, the most common signs of a cerebellar disorder involve a disturbance in muscle control.
Symptoms or signs include:
- lack of muscle control and coordination
- difficulties with walking and mobility
- slurred speech or difficulty speaking
- abnormal eye movements
There are many disorders of the cerebellum, including:
The main symptom of cerebellum dysfunction is ataxia.
Ataxia is a loss of muscle coordination and control. An underlying problem with the cerebellum, such as a virus or brain tumor, can cause these symptoms.
Loss of coordination is often the first sign of ataxia, and speech difficulties follow soon after.
Other symptoms include:
- blurry vision
- difficulty swallowing
- difficulties with precise muscle control
- changes in mood or thinking
Several factors can cause ataxia, including:
- poisons that brain damage
- head injury
- multiple sclerosis
- cerebral palsy
- chicken pox and other viral infections
Sometimes ataxia is reversible when the underlying cause is treatable. In other cases, ataxia resolves without treatment.
Ataxia disorders are degenerative conditions. They can be either genetic or sporadic.
A genetic mutation causes genetic or hereditary ataxia. There are several different mutations and types.
These disorders are rare and even the most common type, Friedreich’s ataxia, affects only 1 in 40,000 people.
The doctor will diagnose Friedreich’s ataxia after ruling out a range of other causes. Genetic testing can identify the condition, which usually appears in childhood.
Sporadic ataxia is a group of degenerative movement disorders for which there is no evidence of inheritance. This condition usually progresses slowly and can develop into multiple system atrophy.
It presents a range of symptoms, including:
- problems with heart rate
- erectile dysfunction
- loss of bladder control
These disorders usually get worse over time. There is no specific treatment to soothe or resolve symptoms, except in cases of ataxia where the cause is a vitamin-E deficiency.
There are several devices that can help people with irreversible ataxia, such as canes and specialized computers to support mobility, speech, and precise muscle control.
Ataxia caused by toxins
The cerebellum is vulnerable to poisons, including alcohol and certain prescription medications.
These poisons damage nerve cells in the cerebellum, leading to ataxia.
The following toxins might cause ataxia:
- drugs, especially barbiturates and benzodiazepines
- heavy metals, including mercury and lead
- solvents, such as paint thinners
Treatment and expected recovery time depend on the toxin involved and the extent of brain damage.
A virus can cause ataxia.
This disorder is called acute cerebellar ataxia, and it is most commonly occurs in children. Ataxia is a rare complication of the chicken pox virus.
There is no treatment for viral ataxia. It usually resolves in a few months, once the viral infection goes away.
Ataxia caused by stroke
Stroke is a clot or bleed in any part of the brain. The cerebellum is a less common site for stroke than the cerebrum, but it can still occur there.
A clot or bleed in the cerebellum can cause the following:
Treating the stroke might resolve the ataxia. Occupational and physical therapy can help manage any permanent damage.
Tumor in the cerebellum
Tumors are abnormal cells that can either grow in the brain or migrate there from a different part of the body. These tumors might be benign and not spread through the body. Malignant tumors grow and spread, leading to cancer.
Symptoms of a tumor in the cerebellum include:
- a headache
- vomiting without nausea
- difficulties with coordination
Diagnosis and treatment will vary based on age, the overall state of health, the course of the disease, the potential outlook, and other factors.
Preserving overall brain health is the best way to avoid damage to the cerebellum.
Reducing the risk of stroke, brain injury, and exposure to poisons can help prevent some forms of ataxia.
- Quitting smoking: Smoking increases the risk of stroke by thickening the blood and raising blood pressure.
- Limiting alcohol use: Large amounts of alcohol can damage the cerebellum. Alcohol also raises blood pressure, which increases the risk of stroke.
- Exercise: Regular physical activity benefits the heart and blood vessels and reduces the risk of stroke. The Centers for Disease Control and Prevention (CDC) recommend 2.5 hours of exercise per week.
- Protecting the head: Wearing seat belts, helmets, and fixing safety hazards in the home reduce the risk of a brain injury. People should take measures to prevent falls. Parents should also ensure that children have no access to balconies or fire escapes.
- Avoid handling lead: Construction companies no longer use lead, but older homes might have lead pipes and paint. People should keep homes clean from dust that might contain lead and stop children from playing in the soil.
Regular consultation and management can help limit the physical restrictions of genetic ataxia.
Why is the cerebellum so important?