A person having a seizure cannot will his or her body to stop movements or activities, or respond to instructions. The extent to which normal activities are affected depends on how much of the brain is involved in the seizure. Abnormal electrical activity limited to a part of the brain is called a partial seizure. Seizure activity that involves the entire brain from the outset is called a generalized seizure. Seizures that begin in a part of the brain and spread to involve the entire brain are called secondarily generalized seizures.
Epilepsy is a disorder of the central nervous system.
It can be caused by injury or trauma to the brain such as a head injury, diseases that affect the central nervous system like meningitis or encephalitis, stroke, poisoning, or lack of oxygen to the brain. More than half the cases of epilepsy are idiopathic or have no identifiable origin. Many of these are believed to be genetic. Epilepsy is not a disease and is not contagious. New cases of epilepsy most often occur in children and the elderly.