Spotlight on Seizures

Would you know how to spot a seizure? Learn more about the many seizure types!

What is a seizure?

A seizure is a short change in normal brain activity that can cause changes in awareness, behavior, or body movement. There are over 30 different types of seizures.1 The signs of a seizure depend on the area of the brain affected.

Seizures might look different than you expect. In the movies and on TV, they often show a person falling to the ground, shaking, and becoming unaware of what’s going on around them. That’s one kind of seizure, but it’s not the most common. More often, a person having a seizure may seem confused, stare into space, wander, make unusual movements, or can’t answer questions or talk.

About 1 out of 10 people will have a seizure in their lives,2 which means seizures are common. It’s important to be able to recognize seizure symptoms and know how to help.

What causes seizures?

Epilepsy causes repeated seizures, but other problems can cause seizures too, including:

Brain injury.
High fever.
Alcohol or drug withdrawal.

Did you know there are more than 30 types of seizures? Learn the signs and how to help.

CDC supports the Epilepsy Foundation to train school nurses and staff, daycare personnel, law enforcement, emergency responders, and older adult caregivers how to recognize seizures and provide first aid. Learn more.

Types of Seizures

There are two groups of seizures: generalized seizures and focal seizures. These terms are used to identify where in the brain a seizure starts. Both of these types of seizures can cause a person to have physical movements, which doctors call “motor symptoms.” Both types of seizures can affect awareness.3

Generalized Seizures

Generalized seizures affect both sides of the brain. There are two groups of generalized seizures:

Tonic-clonic seizures (once called grand mal seizures) are the most well-known type of seizure. These seizures can make a person:
- Cry out.
- Lose consciousness.
- Fall to the ground.
- Have muscle jerks or spasms.
The person may feel tired after a tonic-clonic seizure.
Absence seizures (once called petit mal seizures) can cause rapid eye blinking or a few seconds of staring into space.

Focal Seizures

Focal seizures are located in just one area of the brain. These seizures are also called partial seizures. There are at least three different types of focal seizures.

Simple focal seizures affect a small part of the brain. These seizures can cause jerking or a change in sensation, such as a strange taste or smell, or a “funny feeling” in the stomach.
Complex focal seizures can make a person with epilepsy confused. The person will be unable to respond to questions or direction for up to a few minutes. A person with this type of seizure may move around without purpose or direction.
Secondary generalized seizures start in one part of the brain, but then spread to both sides of the brain. In other words, the person first has a focal seizure, followed by a generalized seizure.

Seizures may last as long as a few minutes.

What do I do if someone has a seizure?

Not all seizures are emergencies and most will end within a few minutes. The first response is to remain calm, provide care, and comfort. Time the seizure, and check for a medical identification bracelet or other emergency information.

Learn more about seizure first aid and what you can do to help during a seizure.

Read more about epilepsy and find the answers to common questions.

References

National Institutes of Health. The Epilepsies and Seizures: Hope through Research . Accessed September 8, 2017.
Hauser WA, et al. Descriptive epidemiology of epilepsy: Contributions of population-based studies from Rochester, Minnesota. Mayo Clinic Proceedings. 1996;71(6):576-86.
Fisher RS, et al. Operational classification of seizure types by the International League Against Epilepsy: Position paper of the ILAE Commission for Classification and Terminology. Epilepsia. 2017;58: 522–530.