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myoclonic

Epilepsy

Epilepsy is a brain disorder that causes people to have recurring seizures. The seizures happen when clusters of nerve cells, or neurons, in the brain send out the wrong signals. People may have strange sensations and emotions or behave strangely. They may have violent muscle spasms or lose consciousness.

Epilepsy has many possible causes, including illness, brain injury, and abnormal brain development. In many cases, the cause is unknown.

Doctors use brain scans and other tests to diagnose epilepsy. It is important to start treatment right away. There is no cure for epilepsy, but medicines can control seizures for most people. When medicines are not working well, surgery or implanted devices such as vagus nerve stimulators may help. Special diets can help some children with epilepsy.

NIH: National Institute of Neurological Disorders and Stroke

Seizures

Seizures are symptoms of a brain problem. They happen because of sudden, abnormal electrical activity in the brain. When people think of seizures, they often think of convulsions in which a person's body shakes rapidly and uncontrollably. Not all seizures cause convulsions. There are many types of seizures and some have mild symptoms. Seizures fall into two main groups. Focal seizures, also called partial seizures, happen in just one part of the brain. Generalized seizures are a result of abnormal activity on both sides of the brain.

Most seizures last from 30 seconds to 2 minutes and do not cause lasting harm. However, it is a medical emergency if seizures last longer than 5 minutes or if a person has many seizures and does not wake up between them. Seizures can have many causes, including medicines, high fevers, head injuries and certain diseases. People who have recurring seizures due to a brain disorder have epilepsy.

NIH: National Institute of Neurological Disorders and Stroke

Cerebellar Disorders

When you play the piano or hit a tennis ball you are activating the cerebellum. The cerebellum is the area of the brain that controls coordination and balance. Problems with the cerebellum include:

Treatment of cerebellar disorders depends on the cause. In some cases, there is no cure but treatment may help with symptoms.

NIH: National Institute of Neurological Disorders and Stroke

Dementia

What is dementia?

Dementia is a loss of mental functions that is severe enough to affect your daily life and activities. These functions include:

It is normal to become a bit more forgetful as you age. But dementia is not a normal part of aging. It is a serious disorder which interferes with your daily life.

What are the types of dementia?

The most common types of dementia are known as neurodegenerative disorders. These are diseases in which the cells of the brain stop working or die. They include:

Other conditions can cause dementia or dementia-like symptoms, including:

Who is at risk for dementia?

Certain factors can raise your risk for developing dementia, including:

What are the symptoms of dementia?

The symptoms of dementia can vary, depending on which parts of the brain are affected. Often, forgetfulness is the first symptom. Dementia also causes problems with the ability to think, problem solve, and reason. For example, people with dementia may:

Some people with dementia cannot control their emotions and their personalities may change. They may become apathetic, meaning that they are no longer interested in normal daily activities or events. They may lose their inhibitions and stop caring about other peoples' feelings.

Certain types of dementia can also cause problems with balance and movement.

The stages of dementia range from mild to severe. In the mildest stage, it is just beginning to affect a person's functioning. In the most severe stage, the person is completely dependent on others for care.

How is dementia diagnosed?

Your health care provider may use many tools to make a diagnosis:

What are the treatments for dementia?

There is no cure for most types of dementia, including Alzheimer's disease and Lewy body dementia. Treatments may help to maintain mental function longer, manage behavioral symptoms, and slow down the symptoms of disease. They may include:

Can dementia be prevented?

Researchers have not found a proven way to prevent dementia. Living a healthy lifestyle might influence some of your risk factors for dementia.

Genetic Brain Disorders

A genetic brain disorder is caused by a variation or a mutation in a gene. A variation is a different form of a gene. A mutation is a change in a gene. Genetic brain disorders affect the development and function of the brain.

Some genetic brain disorders are due to random gene mutations or mutations caused by environmental exposure, such as cigarette smoke. Other disorders are inherited, which means that a mutated gene or group of genes is passed down through a family. They can also be due to a combination of both genetic changes and other outside factors.

Some examples of genetic brain disorders include:

Many people with genetic brain disorders fail to produce enough of certain proteins that influence brain development and function. These brain disorders can cause serious problems that affect the nervous system. Some have treatments to control symptoms. Some are life-threatening.

Mitochondrial Diseases

Metabolism is the process your body uses to make energy from the food you eat. Food is made up of proteins, carbohydrates, and fats. Chemicals in your digestive system (enzymes) break the food parts down into sugars and acids, your body's fuel. Your body can use this fuel right away, or it can store the energy in your body tissues. If you have a metabolic disorder, something goes wrong with this process.

Mitochondrial diseases are a group of metabolic disorders. Mitochondria are small structures that produce energy in almost all of your cells. They make it by combining oxygen with the fuel molecules (sugars and fats) that come from your food. When the mitochondria are defective, the cells do not have enough energy. The unused oxygen and fuel molecules build up in the cells and cause damage.

The symptoms of mitochondrial disease can vary. It depends on how many mitochondria are defective, and where they are in the body. Sometimes only one organ, tissue, or cell type is affected. But often the problem affects many of them. Muscle and nerve cells have especially high energy needs, so muscular and neurological problems are common. The diseases range from mild to severe. Some types can be fatal.

Genetic mutations cause these diseases. They usually happen before age 20, and some are more common in infants. There are no cures for these diseases, but treatments may help with symptoms and slow down the disease. They may include physical therapy, vitamins and supplements, special diets, and medicines.

Movement Disorders

Movement disorders are neurologic conditions that cause problems with movement, such as:

There are many different movement disorders. Some of the more common types include:

Causes of movement disorders include:

Treatment varies by disorder. Medicines can cure some disorders. Others get better when an underlying disease is treated. Often, however, there is no cure. In that case, the goal of treatment is to improve symptoms and relieve pain.

Spinal Muscular Atrophy

What is spinal muscular atrophy (SMA)?

Spinal muscular atrophy (SMA) is a group of genetic diseases that damages and kills motor neurons. Motor neurons are a type of nerve cell in the spinal cord and lower part of the brain. They control movement in your arms, legs, face, chest, throat, and tongue.

As the motor neurons die off, your muscles start to weaken and atrophy (waste away). The muscle damage gets worse over time and can affect speaking, walking, swallowing, and breathing.

What are the types of spinal muscular atrophy (SMA) and what are their symptoms?

There are different types of SMA. They are based on how serious the disease is and when the symptoms start:

What causes spinal muscular atrophy (SMA)?

Most types of SMA are caused by a change in the SMN1 gene. This gene is responsible for making a protein that the motor neurons need to be healthy and to function. But when part of the SMN1 gene is missing or abnormal, there isn't enough protein for the motor neurons. This causes the motor neurons to die off.

Most people have two copies of the SM1 gene - one from each parent. SMA normally only happens when both copies have the gene change. If only one copy has the change, there usually aren't any symptoms. But that gene could be passed down from parent to child.

Some of the less common types of SMA may be caused by changes in other genes.

How is spinal muscular atrophy (SMA) diagnosed?

Your health care provider may use many tools to diagnose SMA:

Parents who have a family history of SMA may want to do a prenatal test to check to see whether their baby has an SMN1 gene change. An amniocentesis or in some cases a chorionic villi sampling (CVS) is used to get the sample for testing.

In some states, genetic testing for SMA is part of newborn screening tests.

What are the treatments for spinal muscular atrophy (SMA)?

There is no cure for SMA. Treatments can help manage symptoms and prevent complications. They may include:

NIH: National Institute of Neurological Disorders and Stroke

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