FOCAL (PARTIAL SEIZURES)
A focal (partial) seizure occurs when the excessive electrical discharge is limited to one part of the brain. Focal (partial) seizures are the most common type of seizure in adults. Sometimes, seizures begin as focal (partial) and spread to become generalized. These are referred to as bilateral tonic-clonic generalized seizures.
The two most common type of focal (partial) seizures are focal aware (simple partial) and focal impaired (complex partial) seizures. During a focal aware seizure, awareness remains intact. In a focal impaired seizure, awareness is impaired.
Focal Aware (Simple Partial) Seizures
During a focal aware seizure, formerly known as a simple partial, the individual remains aware. A focal aware 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 focal aware seizure that may occur alone or may progress to a focal impaired awareness seizure or a generalized seizure. If the aura indicates the onset of a focal impaired (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 focal aware 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.
Focal Impaired Awareness (Complex Partial) Seizures
During a focal impaired awareness seizure, formerly known as complex partial, psychomotor or temporal lobe seizure, the person 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 focal aware seizure that can occur alone or as the onset of a focal impaired awareness seizure. In a focal impaired awareness 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 focal impaired awareness 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.
