Types of Seizures

Neurology Now
November/December 2008
Volume 4(6)
p 36
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Generalized seizures involve the entire brain, while partial seizures occur in just one part of the brain. Some people with epilepsy may experience different kinds of seizures, while others may only have one type. According to the University of Tennessee Medical Center, there are four common types:

TONIC-CLONIC SEIZURES Previously known as grand mal seizures, tonic-clonic seizures are generalized. Sometimes a person with this type of epilepsy will experience an “aura,” or warning, before the seizure begins. During the tonic phase, a person typically stiffens and falls to the ground unconscious. The clonic phase begins with strong, rhythmic shaking movements. Drooling and loss of bladder or bowel control may occur. The seizure normally stops after a minute or two.

ABSENCE SEIZURES These seizures, also called petit mal, are more common in children and are sometimes mistaken for daydreaming. Like tonic-clonic seizures, they are generalized but are milder. People experiencing this type of seizure lose awareness of what is happening around them, but they rarely fall to the ground. Their eyes may roll back, they may stare, or their eyelids may flutter. Absence seizures typically start suddenly, last a few seconds, and then stop suddenly.

SIMPLE PARTIAL SEIZURES These seizures involve only one part of the brain. Symptoms will vary depending on which part of the brain is involved. Unlike tonic-clonic and absence seizures, people experiencing simple partial seizures remain fully conscious. Common symptoms include stiffness or shaking in one part of the body or an abnormal feeling such as numbness or an unpleasant smell or taste. Simple partial seizures usually last for less than a minute.

COMPLEX PARTIAL SEIZURES These are the most common seizure type. They involve only one part of the brain, but the person's conscious state is altered. He or she may appear confused and do unusual things like make sounds, fiddle with clothing, or make chewing movements. Complex partial seizures only last for one to two minutes.

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