We may have some ideas of what a seizure looks like -- convulsions, twitching, drooling. But not all seizures are the same. Doctors classify seizures into two broad groups: focal seizures (sometimes called partial seizures) and generalized seizures. Focal seizures occur in just one area of the brain; these types of seizures are experienced by about 60 percent of people with epilepsy [source: NINDS]. Generalized seizures occur in both sides of the brain.
But within those two groups, there's still a wide range of seizure types, which in turn create an immense range of sensations. Focal seizures are further broken down as either simple or complex. When a person suffers a simple focal seizure, he or she maintains consciousness, but experiences abnormal feelings or sensations. The person might sense things that aren't there. Sometimes a simple focal seizure is an aura, or an indication that a complex focal seizure is about to come. A complex focal seizure does involve a loss of consciousness, so that the person enters a dreamlike state. To an observer, a person experiencing a complex focal seizure may engage in repetitive behaviors including twitching, blinking or walking in a circle.
There are many more types of generalized seizures. These seizures include:
- Absence seizures generally occur in children. As the name implies, the person briefly goes absent from the conscious world. It's like the child is staring into space, though eyelids may flutter and muscles may twitch. These seizures last for just a few seconds, and then the child resumes activity almost as quickly as before.
- Clonic seizures cause convulsions, or jerking movements on both sides of the body.
- Myoclonic seizures involve jerking of the upper body and the limbs. It may look like the person has been shocked.
- Tonic seizures result in sudden stiffness in the muscles. These seizures are more common in sleep.
- Atonic seizures involve a loss of muscle control, causing the person to droop or fall. Although these seizures may be quick, they can cause sudden falls, resulting in further injury.
- Tonic-clonic seizures involve a combination of both tonic and clonic seizure symptoms. The person quickly stiffens, loses consciousness and then convulses with repeated jerking of the arms and legs.
You may have heard the phrases "grand mal" and "petit mal" used to describe a seizure. These terms are considered outdated and inaccurate, so you shouldn't hear a doctor using them. Tonic-clonic seizure is the more appropriate term for a grand mal seizure, while absence seizures describe the seizures formally known as petit mal.
Most seizures are generally brief, lasting either just a few seconds or at most a few minutes. The period after a seizure is known as the postictal state; it may include a headache, soreness, confusion and fatigue. If a seizure lasts longer than five minutes, the person is entering a state known as status epilectus and requires medical attention.
Not all seizures, however, require immediate medical attention. If someone near you has a seizure, you shouldn't leave them to call 911. The most important thing to do is remain calm and take actions that will prevent the person from harming himself or herself. Roll the person on his or her side to prevent choking, but don't try to put anything in the mouth, like a spoon. Many onlookers try to do this, thinking it will prevent a seizure sufferer from swallowing his or her own tongue, but this won't happen. Cushioning the person's head, loosening tight clothing and removing nearby objects are all actions that will prevent the person from causing personal injury or harm, but if the person wants to wander around, allow him or her to do so. Stay with the person until the seizure ends and be patient as he or she recovers from the seizure. Then you can make the determination of who to call. It may be 911 if the person is pregnant, the seizure lasts for more than five minutes or the person becomes injured during the seizure.
So how do these individual seizures relate to a diagnosis of epilepsy? Turn the page to find out.