What is a Focal Seizure (Partial Seizure)?

Have you or someone else noticed part of your body moving or shaking involuntarily? Do you have short periods when you feel confused, have memory loss, or appear to act unusual? Are you sometimes unaware of your actions, or do you even pass out for a few moments? If so, you may be experiencing focal seizures. These occur when you have a condition called epilepsy. Focal seizures (formally called partial seizures) can be scary and frustrating. But they can usually be controlled.

Your brain uses short bursts of electricity as signals. These signals allow areas of the brain to communicate with each other. These signals also travel from the brain to the rest of your body.

Sometimes the signals become excessive. When this happens in one area of the brain, it's called a focal seizure. The excessive signals cause part of the body to work abnormally. Then you may twitch, feel confused, or pass out for a moment. Focal seizures can present in many ways.

• Focal onset aware seizures (previously simple partial seizures) often have only a few minor symptoms, such as hand twitching, visual changes, smelling an unusual odor, or feeling a sense of déjà-vu. There is no loss of consciousness.
• Focal impaired awareness seizures (previously complex partial seizures) are often linked with more abnormal behavior. They may also affect your mental functioning to some degree. You may have a lowered level of consciousness, mental confusion, or loss of memory.

Seizures can be caused by irritation or damage to the brain from injury, scar formation, tumors, stroke, or infection. Usually the cause is unknown. But most partial seizures can be successfully treated. With treatment, most people with seizures lead normal, fulfilling lives.