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Seizures are the only visible symptom of epilepsy. There are different kinds of seizures. Symptoms of each type can affect people in different ways. Seizures typically last from a few seconds to a few minutes. You may be alert during the seizure or pass out (lose consciousness). You may not remember what happened during the seizure. Or you may not even realize you had a seizure.
Seizures that make you fall to the ground or make the muscles stiffen or jerk out of control are easy to recognize. But many seizures don't involve these reactions. They may be harder to notice. Some seizures make you stare into space for a few seconds. Others may cause only a few muscle twitches, a turn of the head, or a strange smell or visual disturbance that only you sense.
Epileptic seizures often happen without warning, though some people may have an aura at the start of a seizure. A seizure ends when the abnormal electrical activity in the brain stops and brain activity starts to go back to normal. Seizures may be either partial or generalized.
Partial seizures start in a specific area or place in the brain. The most common types are:
Simple partial seizures. These seizures don't affect consciousness or awareness.
Complex partial seizures. These seizures do affect your level of consciousness. You may become unresponsive. Or you may pass out completely.
Partial seizures with secondary generalization. These seizures start as simple or complex partial seizures. But then they spread (generalize) to the rest of the brain and look like generalized tonic-clonic seizures. These two types can easily be confused. But they are treated in different ways. Most tonic-clonic seizures in adults start as partial seizures and are caused by partial epilepsy. Generalized tonic-clonic seizures are more common in children.
Seizures that start over the entire surface of the brain are called generalized seizures. The main types are:
Generalized tonic-clonic seizures (grand mal seizures). During this type of seizure, the person falls to the ground, the entire body stiffens, and the person's muscles start to jerk or spasm (convulse).
Absence seizures (petit mal seizures). These seizures make a person stare into space for a few seconds. Then the person "wakes up" without knowing that anything has happened.
Myoclonic seizures. These seizures make the body jerk like it's being shocked.
Atonic seizures. These cause a sudden loss of muscle tone that makes the person fall down without warning.
Tonic seizures. These cause the muscles to suddenly contract and stiffen. This often makes the person fall down.
People may refer to seizures as convulsions, fits, or spells. But seizure is the correct term. Convulsions, during which the muscles twitch or jerk, are just one characteristic of seizures. Some seizures cause convulsions, but many don't.
Epileptic seizures are sometimes confused with psychogenic seizures, which are not caused by abnormal electrical function. A psychogenic seizure may be a psychological response to stress, injury, emotional trauma, or other factors.
Not everyone who has a seizure has epilepsy. Seizures that aren't epileptic may be caused by different medical conditions such as poisoning, fever, fainting, or alcohol or drug withdrawal. Seizures that occur at the time of a disease, injury, or illness and stop when the condition improves aren't related to epilepsy. But if seizures keep occurring (become chronic), occurring weeks, months, or even years after the injury or illness, then you have developed epilepsy as a result of the condition.
There are several other conditions with similar symptoms, such as fainting or seizures caused by high fevers.
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