Epilepsy is a neurological condition that from time to time produces brief disturbances in the normal electrical functions of the brain. Normal brain function is made possible by millions of tiny electrical charges passing between nerve cells in the brain and all parts of the body.
When someone has epilepsy, this normal pattern may be interrupted by intermittent bursts of electrical energy that are more intense that usual. They may affect a person's consciousness, body movements, or sensations for a short time. These physical changes are called seizures. When a person has repeated seizures or a tendency to have seizures that can be seen on a brain wave test call an electroencephalogram (EEG), we often say that the person has epilepsy. Epilepsy is sometimes called a seizure disorder. The usual bursts of energy may occur in just one area of the brain (partial seizures) or may affect nerve cells throughout the brain (generalized seizures). Normal brain function cannot return until the electrical bursts stop.
People can be born with conditions of the brain that produce these episodes or they can develop them later in life because of injury, infections, structural abnormalities in the brain, exposure to toxic agents, or for reasons that are unknown.
Illnesses or severe injuries can affect the brain enough to produce a single seizure. When seizures continue to occur for unknown reasons or because of an underlying problem that cannot be corrected, the condition is known as epilepsy. Epilepsy affects people of all ages, nationalities, and races — even animals can have epilepsy.