A seizure disorder (also known as epilepsy) is a condition in which the neurons in the brain function abnormally, resulting in sudden, brief changes in how the brain works. These changes result in seizures, which involve convulsions, muscle spasms, and loss of consciousness. A person needs to have two or more seizures to be classified as having a disorder.
The term "seizure disorder" refers to a condition that occurs when clusters of nerve cells, or neurons, in the brain sometimes signal abnormally. When these brain cells are not working properly, a person's consciousness, movement, or actions may be altered for a short time. These physical changes are called epileptic seizures.
Seizure disorders are more commonly known as epilepsy and affect people of all nationalities and races.
A seizure disorder can be caused by a variety of factors. Anything that disturbs the normal pattern of neuron activity -- from illness to brain damage to abnormal brain development -- can cause a seizure. The condition may develop as the result of abnormality in brain wiring, an imbalance of nerve signaling chemicals called neurotransmitters, or some combination of these factors.
Seizure disorders are not contagious and are not caused by mental illness or mental retardation.
Experiencing a single seizure does not necessarily mean that a person has a seizure disorder. Only when a person has had two or more seizures is he or she considered to have a disorder. Brain scans and electroencephalograms (EEGs) are common tests used to make a diagnosis.
After a person has been diagnosed with a seizure disorder, seizures can be controlled with modern medicines and surgical techniques. In 1997, the U.S. Food and Drug Administration (FDA) approved the vagus nerve stimulator for use in people with seizures that are not well-controlled by medication.