If an electroencephalogram (EEG) is done when there is seizure activity, the change is seen as unusual bursts of energy. These bursts can occur in one area of the brain or throughout the brain. The symptoms or characteristics of the seizure depend on the part of the brain affected. Localized seizures are called simple partial seizures. They remain in one part of the brain, and do not greatly affect consciousness. Complex partial seizures begin in one part of the brain, but spread to other parts and can impair consciousness. Generalized seizures involve the entire brain from the beginning. They usually impair consciousness and may cause muscle jerking. Normal brain function does not resume until these bursts of energy have stopped and the brain has had time to recover. Seizures can occur while a person is awake, or while a person is sleeping.

Many severe injuries and illnesses, such as a tumor, infection, or stroke, can cause seizures. Often, no definite cause for the seizures can be found. When seizures continue on a chronic basis without a clear, underlying cause, the condition is called epilepsy.

Although epilepsy is often thought of as a childhood condition, it can develop at any age. About 30 percent of cases develop in early childhood and in adolescence. People over age 65 also are more at risk for developing epilepsy.

Although you generally don't need extra sleep if you have epilepsy, you should try to get enough sleep each night. If you stay up late several nights in a row, you greatly increase your risk for having a seizure. Health care providers often ask their patients to stay up late before having an EEG examination because a lack of sleep increases the chances that seizure activity will show up during the exam. If you feel tired even with adequate sleep, talk with your health care provider. Your medication dosage may need to be changed.

Each state's regulations are different, but generally they require that you be seizure-free for a specific amount of time before you are allowed to drive. Some states require a health care provider's note. You can safely drive a motor vehicle if your seizures are under control.

Mountain climbing is risky both because of the danger of falling if you have a seizure and because the thinner air at higher altitudes can put you at greater risk for a seizure. Swimming and other water sports are risky because you can drown if you lose consciousness. Contact sports like football can put you at risk for brain trauma, which can make seizures worse. Other sports to avoid include skydiving and hang gliding. People with epilepsy should not exercise when the weather is very hot, because excess heat and dehydration can trigger seizures.

Alcohol can be dangerous when taken with sedatives such as phenobarbital. Mixing alcohol with these drugs can lead to coma or death. Drinking large amounts of alcohol can increase the risk for seizures. Moderate drinking -- having a drink or two a day -- may or may not affect you. Talk with your health care provider to see if your medication or your condition may cause a problem if you drink.

One of the most important factors in diagnosing epilepsy is a patient's history of seizures. The EEG may detect brain wave patterns that may indicate seizures. A PET scan may help the doctor find out which area(s) of the brain are affected by the seizures, but it is not necessary for the diagnosis. Other imaging methods also may be used to find areas of the brain that may have been previously damaged or to find growths that might be causing the seizures.

Drugs called anti-epileptic or anticonvulsant medications are the most common treatments for epilepsy. These medications can prevent seizures from occurring. They must be taken carefully to maintain the proper level of the drug in the body to prevent seizures. If medication does not work, health care providers may turn to surgery, a special ketogenic diet, or an implanted device that stimulates the vagus nerve leading to the brain.