Seizures are episodes that occur when there is a sudden, brief change in electrical activity in the brain. When people experience seizures, their consciousness, movement, or actions may be altered for a short time. They affect people of all races and nationalities.
A person can have a seizure for a number of reasons. Some people can experience a seizure and not have
epilepsy. For example, many young children have convulsions from fevers
(see Febrile Seizures).
Other
types of seizures include those caused by an imbalance of body fluids or chemicals, such as low blood sugar in people with
diabetes, or by alcohol or drug withdrawal.
- Severe head injury
- An infection of the brain
- Eclampsia
- Tumor
- Stroke
- Certain other medical conditions.
Although there are many types of seizures, each with its own symptoms, you should consult a healthcare provider if you or a member of your family experiences one or more of these possible symptoms:
- "Blackouts" or periods of confused memory
- Episodes of staring or unexplained periods of unresponsiveness
- Involuntary movement of arms and legs
- "Fainting spells," with incontinence or followed by excessive fatigue
- Odd sounds, distorted perceptions, or episodic feelings of fear that cannot be explained.
When someone has experienced a seizure, a healthcare provider will usually order an electroencephalogram, or EEG, to determine what type of seizure the person may have had and whether there are any detectable abnormalities in the person's brain waves. The doctor also may order brain scans to identify abnormalities that may be visible in the brain.
If a person has had two or more seizures, he or she is often diagnosed with
epilepsy.
Seizures can be generalized, meaning that all brain cells are involved. One type of generalized seizure consists of a convulsion with a complete loss of consciousness. Another type looks like a brief period of fixed staring.
A seizure can be "partial" when those brain cells not working properly are limited to one part of the brain. Such partial seizures may cause periods of "automatic behavior" and altered consciousness. This is typified by purposeful-looking behavior, such as buttoning or unbuttoning a shirt. Such behavior, however, is unconscious, may be repetitive, and is usually not remembered.
