A partial seizure occurs when the excessive electrical discharge is limited to one part of the brain. Partial seizures are the most common type of seizure in adults. Sometimes, seizures begin as partial and spread to become generalized. These are referred to as partial seizure secondarily generalized.
The two most common type of partial seizures are simple and complex partial seizures. During a simple partial seizure, awareness remains intact. In a complex partial seizure, awareness is impaired.
During a simple partial seizure, formerly known as a focal seizure, the individual remains aware. A simple partial seizure may involve sensory, motor, psychic, or autonomic symptoms. These symptoms result in the person experiencing an unusual sensation, feeling or movement called an aura. The aura may be a distortion in sight, sound, or smell where a person sees, hears, smells things that are not there. It may also be a sudden uncontrollable jerky movement of one area of the body, such as the arm, leg or face. A person may experience a sudden overwhelming emotion, such as joy, sadness, fear or anger. Others may experience stomach upset, dizziness, a shiver, a tingling or burning sensation, pallor or flushing. Occasionally there will be the experience of déjà vu during which a person has the sensation of having experienced something before.
The seizure usually begins suddenly and lasts seconds to minutes. An aura is a simple partial seizure that may occur alone or may progress to a complex partial seizure or a generalized seizure. If the aura indicates the onset of a complex partial seizure or generalized seizure, it can sometimes be used as a warning signal to allow a person to take the necessary precautions to avoid injury.
During a simple partial seizure, it is important to provide reassurance and emotional support to the individual. First Aid may be necessary if the seizure becomes a generalized seizure.
During a complex partial seizure, formerly known as psychomotor or temporal lobe seizure, the persons experiences altered awareness and may appear dazed and confused. A dreamlike experience may occur. In some cases, the individual will be unable to respond or will do so incompletely or inaccurately. In other cases, the individual will lose contact.
The seizure often begins with an unusual sensation, feeling or movement referred to as an aura. An aura can take many forms including a strange feeling in the upper abdomen, a feeling of fear or a hallucination. An aura is a simple partial seizure that can occur alone or as the onset of a complex partial seizure. In a complex partial seizure, the aura often occurs just before awareness is altered and it is often used as a warning.
Random purposeless movements over which the individual has no control called automatisms often characterize the seizure. These may include movements such as chewing motions, mumbling, lip smacking, head turning, pulling at clothing, picking motions in the air or random walking. Occasionally, there are more dramatic behavioural changes such as screaming, undressing or laughing. Once the pattern has been established, the same set of actions often occurs with each seizure.
The seizure usually lasts for between one and two minutes and is often followed by a postictal period of disorientation and confusion.
It is important when witnessing a complex partial seizure to speak calmly to the individual. Explain to others what is happening. Guide the individual away from hazards but DO NOT restrain. Stay with the individual until complete awareness returns and offer help getting home.