For a given seizure type, seizure usually starts in the same part of the brain each time. Once initiated, the seizure may remain localized or spread to adjacent areas, and in some cases, may travel to the opposite hemisphere (contralateral spread).

Learn about this burst of electrical activity in the brain and what causes it. Find out what to do if you see someone having a seizure.

A seizure is abnormal electrical activity in your brain that temporarily affects your consciousness, muscle control and behavior.

Seizures are changes in your brain’s electrical activity. Learn more about types of seizures, causes and symptoms, and how you can help someone having a seizure.

You might be aware of having a seizure and remember it afterwards, or you might not. Symptoms of epilepsy often start in young children and people over 50, but it can happen at any age.

Epilepsy (sometimes referred to as a seizure disorder) can have many different causes and seizure types. Epilepsy varies in severity and impact from person to person and can be accompanied by a range of co-existing conditions.

A seizure involves a surge of abnormal electrical activity within the brain and may cause uncontrollable movements, temporary loss of consciousness, or other neurologic manifestations.

A seizure is a burst of uncontrolled electrical activity between brain cells (also called neurons or nerve cells) that causes temporary abnormalities in muscle tone or movements (stiffness, twitching or limpness), behaviors, sensations or states of awareness.

A seizure is a sudden surge of electrical activity in the brain. Read about types of seizures, symptoms, diagnosis, treatment, prevention, and more.

Types of Seizure There are two primary types of seizure —focal and generalized—and these are categorized based on the areas of the brain that are affected.