While the brain is complex and has billions of nerve cells, the basic anatomy is easy to understand. One part of the brain, the cerebellum, is involved in virtually all movement.
That part of the brain helps a person drive, throw a ball, or walk across the room.
Problems with the cerebellum are uncommon and mostly involve movement and coordination difficulties. This article will give a brief summary of anatomy, purpose, and disorders of the cerebellum. It will also offer tips on preserving brain health.
Briefly, the brain is divided into the cerebrum, brainstem, and cerebellum.
The cerebellum is the area found at the back and bottom of the brain.
The cerebrum is the part of the brain involved in the higher levels of thinking and action. Four lobes or sections make up the cerebrum. Each lobe performs a different job.
Four brain lobes
The frontal lobe is named for its location at the front and top of the brain. The frontal lobe is associated with the highest levels of human thinking and behavior such as planning, judgment, decision making, impulse control, and attention.
The parietal lobe is on top of the brain and behind the frontal lobe. This lobe is responsible for taking in sensory information. The parietal lobe is responsible for understanding someone’s position in their environment.
The temporal lobe is at the lower front of the brain. This lobe is associated with visual memory, language, and emotion.
Finally, the occipital lobe is located at the back of the brain. The occipital lobe processes what a person sees.
Brainstem and cerebellum
Along with the cerebrum, the other parts of the brain include the cerebellum and brainstem.
The brainstem manages vital functions such as breathing, circulation, sleeping, digestion, and swallowing. These are the involuntary functions controlled by the autonomic nervous system. The brainstem also controls reflexes.
The cerebellum is the area found at the back and bottom of the brain and behind the brainstem. The cerebellum has several roles related to movement and coordination, which include:
- Coordinating movement: Most body movements require the coordination of multiple muscle groups. The cerebellum times muscle actions so that the body can move smoothly.
- Maintaining balance: The cerebellum has special sensors that detect shifts in balance and movement. It then sends signals for the body to adjust and move.
- Vision: The cerebellum is responsible for coordinating eye movements.
- Motor learning: The cerebellum helps the body learn movements that require practice and fine-tuning. For example, the cerebellum plays a role in learning the movements needed to ride a bicycle.
- Other functions: Researchers believe the cerebellum has some role in thinking, including thoughts related to language and mood. These functions are not yet well understood.
The most common signs of a cerebellar disorder involve a disturbance in muscle control. This is because the cerebellum controls balance and voluntary movements.
Symptoms or signs include:
- Lack of muscle control and coordination
- Difficulty walking
- Slurred speech or difficulty speaking
- Abnormal eye movements
There are many disorders of the cerebellum including strokes, brain bleeding, toxins, genetic malformations, infection, and cancer. Some disorders of the cerebellum are described below.
Ataxia is a loss of muscle coordination and control due to a problem with the cerebellum. An underlying problem such as a virus or brain tumor can cause the symptoms.
Loss of coordination is often an initial sign of ataxia and difficulty speaking commonly follows.
Other symptoms include blurry vision, difficulty swallowing, tiredness, difficulty with precise muscle control, and changes in mood or thinking.
Blurry vision is a symptom of ataxia.
There are several disorders that cause the symptom of ataxia, such as:
- Poisons damaging the brain
- Head injury
- Multiple sclerosis
- Cerebral palsy
- Chickenpoxand other viral infections
Sometimes ataxia is reversible when the underlying cause is treated. In other cases, ataxia goes away on its own.
Ataxia disorders are a group of degenerative disorders that are defined as genetic or sporadic.
Genetic or hereditary ataxia is caused by a genetic mutation. There are several different mutations and types of hereditary ataxia. These disorders are rare and the most common type, Friedreich’s ataxia, affects 1 in 50,000 people.
Diagnosis is made after extensive testing and ruling out other causes. Genetic testing can identify Friedreich’s ataxia, which usually appears in childhood.
Sporadic ataxia is a group of degenerative movement disorders for which there is no evidence of inheritance. Lack of coordination is usually the first symptom, and many develop difficulty with speaking.
Sporadic ataxia usually progresses slowly and can develop into multiple system atrophy. This condition has symptoms of fainting, problems with heart rate, erectile dysfunction, and loss of bladder control.
These disorders usually get worse over time. There is no specific treatment to ease or stop symptoms of the disorder, except in cases of ataxia where a lack of vitamin E is a cause.
There are numerous devices such as canes and specialized computers to help movement, 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, which leads to ataxia. The following toxins are associated with ataxia:
- Drugs, especially barbiturates and benzodiazepines
- Heavy metals such as mercury and lead
- Solvents such as paint thinners
Treatment and expected recovery depend on the toxin involved and damage to the brain.
Ataxia caused by a virus
A virus can cause ataxia. This disorder is called acute cerebellar ataxia and most commonly affects children. The chickenpox virus is known to have ataxia as a rare complication.
Other viruses associated with acute cerebellar ataxia are Coxsackie virus, Epstein-Barr, and HIV. Lyme disease, caused by bacteria, has also been associated with this condition.
There is no treatment for ataxia caused by a virus. Ataxia usually disappears in a few months once the viral infection goes away.
Ataxia caused by stroke
Stroke, which is either a clot or bleed in the brain, can affect any part of the brain. The cerebellum is a less common site for stroke than the cerebrum.
A clot or bleed in the cerebellum can cause ataxia, headache, dizziness, nausea, and vomiting.
Treatment of the stroke may resolve the ataxia. Occupational and physical therapy can help cope with any permanent damage.
Tumor in the cerebellum
Vomiting without nausea is one of the symptoms of a tumor in the cerebellum.
Tumors are abnormal cells that can grow in the brain. These tumors can start in the brain or migrate from a different part of the body. These tumors may be benign, where they do not spread through the body. Malignant tumors grow and spread and are called cancer.
Symptoms of a tumor in the cerebellum include:
- Vomiting without nausea
- Difficulty walking (ataxia)
- Lack of coordination
Diagnosis and treatment will vary based on age, health, disease course, expectations for treatment, and other factors.
Protecting the cerebellum
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 avoid 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.
- Engaging in physical activity. Regular physical activity benefits the heart and blood vessels and reduces the risk of stroke. The Centers for Disease Control and Prevention (CDC) recommend 5 hoursof exercise per week.
- Protecting the head. Wearing seat belts, helmets, and fixing safety hazards in the home reduces the risk of a brain injury. People should take measures to prevent falls. Parents should also ensure that children can’t access balconies or fire escapes.
- Avoid handling lead. Lead is no longer used in new construction, but older homes may have lead pipes and paint. People should keep homes clean of dust that may contain lead and stop children from playing in soil.