Epilepsy and Seizures

Seizures are described as either partial or generalized, depending on the part of the brain that is affected and how wide an area of the brain becomes seized by disorderly electrical activity of the brain cells. When one specific part of the brain is affected, the seizure is partial.

There are simple partial and complex partial seizures. A limb may jerk involuntarily during a partial seizure. A person having a simple partial seizure is aware of it happening. With complex partial seizures, a person may have an odd feeling or exhibit strange behavior, such as picking at clothing or wandering aimlessly. People usually do not remember having complex partial seizures.

Sometimes the brain cell activity that causes a partial seizure spreads to the rest of the brain. When the whole brain is affected, a generalized seizure occurs. Generalized seizures, which are somewhat less common than partial seizures, may be brief staring spells, major muscle movements, or full convulsions. Two common types of generalized seizures are absence (petit mal) and tonic-clonic (grand mal) seizures.

During an absence seizure, a person appears to be daydreaming and may have mouth, eye, or limb movements. The person does not answer when called; when the brief episode ends, he or she immediately resumes activity. Several absence seizures can occur in a day. They are common in children and are often outgrown.

During a tonic-clonic seizure, the person falls and loses consciousness. These seizures progress in two main phases. First is the tonic phase, in which the body stiffens and breathing slows or stops. The clonic phase follows, with severe muscle jerking, drooling, and possible loss of bowel or bladder control. Gradually, regular breathing returns and the person regains consciousness.

People may have more than one type of seizure. Correctly identifying the type of seizures a person has helps doctors decide the right treatment for that person.

Seizures are not contagious—you can't “catch” them from others. Most of the time, despite doctors' efforts, no cause is found for seizures. In some cases, though, doctors do find the cause and can eventually stop the seizures.