By The Chronicle Staff

A seizure does not always look like the dramatic convulsions often portrayed on TV.

For someone with epilepsy, a seizure might instead mean staring blankly for several seconds, suddenly becoming confused, experiencing an unexplained feeling of fear or noticing a strange smell or taste. For others, seizures can cause muscles to stiffen or the arms and legs to jerk uncontrollably.

Epilepsy, sometimes called a seizure disorder, is a neurological condition that causes recurring seizures. It can affect people of any age, gender, race or ethnic background, according to information from Mayo Clinic.

Although epilepsy is relatively common, the condition can look very different from one person to another. Understanding those differences — and knowing when a seizure requires emergency medical attention — can be important for patients, families, friends, co-workers and bystanders.

One seizure doesn’t necessarily mean epilepsy

A seizure occurs because of abnormal electrical activity in the brain. Because the brain controls so many functions, symptoms depend largely on where that activity begins and how much of the brain is involved.

Having one seizure, however, does not necessarily mean a person has epilepsy.

Epilepsy generally is diagnosed when someone has experienced at least two unprovoked seizures occurring at least 24 hours apart. An unprovoked seizure is one that does not have an immediate, identifiable cause.

The underlying cause of epilepsy can be identified in some patients, while in others it remains unknown.

Treatment also varies. Anti-seizure medications can control seizures for many patients, while surgery may be an option in some cases. Some people require lifelong treatment, while others eventually become seizure-free. Some children with epilepsy may outgrow the condition.

Seizures can look very different

Symptoms of a seizure can range from subtle to unmistakable.

A person may temporarily become confused, stare into space, lose consciousness or experience stiff muscles or jerking movements of the arms and legs. Others experience

psychological symptoms, including sudden fear, anxiety or a sense of déjà vu — the feeling that something happening now has happened before.

People with epilepsy generally experience similar symptoms from one seizure to another.

Some people also experience an “aura” shortly before certain seizures. An aura is actually part of the seizure and can serve as a warning that more noticeable symptoms are coming.

An aura might produce an unusual sensation in the stomach, dizziness or loss of balance. A person may suddenly experience fear or another emotion or notice a strange taste or smell. Others see flashing or steady lights, colors or shapes. Some may experience hallucinations.

Doctors broadly classify seizures according to where the abnormal brain activity begins.

Focal seizures begin in one area of the brain. Generalized seizures appear to involve both sides of the brain.

Focal seizures may be difficult to recognize

A person experiencing a focal seizure may remain conscious and responsive. These seizures can change emotions or alter the way something looks, sounds, smells, tastes or feels. They also may cause tingling, dizziness, flashing lights or involuntary jerking of an arm or leg.

Other focal seizures impair consciousness.

Someone experiencing one may stare into space and fail to respond normally to people nearby. The person may repeatedly rub their hands, chew, swallow or walk in circles.

Because some focal seizure symptoms resemble those of migraines, narcolepsy or psychiatric conditions, a medical examination and testing may be necessary to determine the cause.

Symptoms also can vary according to the part of the brain affected.

Temporal lobe seizures, for example, can involve emotions and short-term memory. Someone may suddenly experience fear, joy, an unusual smell or taste, déjà vu or a rising sensation in the stomach. During the seizure, the person may stare, smack their lips or repeatedly chew, swallow or move their fingers.

Frontal lobe seizures involve the front portion of the brain, which plays an important role in movement. A person’s head and eyes may turn to one side. The person may not respond when spoken to and could scream or laugh. Repetitive rocking or movements resembling bicycle pedaling also can occur.

Occipital lobe seizures affect the portion of the brain involved in vision. They can cause hallucinations or temporary loss of some or all vision, as well as blinking or unusual eye movements.

Generalized seizures take several forms

Generalized seizures also vary considerably.

Absence seizures, once called petit mal seizures, most commonly occur in children. A child may suddenly stare into space for five to 10 seconds, sometimes accompanied by blinking or lip smacking. Although brief, the seizures can occur repeatedly — in some cases as often as 100 times a day — temporarily interrupting awareness each time.

Tonic seizures cause muscles to become stiff and may cause someone to fall.

Atonic seizures, sometimes called drop seizures, cause a sudden loss of muscle control and also can result in falls.

Clonic seizures involve repeated, rhythmic jerking, usually affecting the neck, face and arms, while myoclonic seizures cause brief, sudden jerks or twitches that often involve the upper body, arms or legs.

Tonic-clonic seizures, formerly called grand mal seizures, are among the most recognizable. A person can suddenly lose consciousness before the body stiffens and begins twitching or shaking. The person also may bite their tongue or lose bladder control.

Know when a seizure is an emergency

While many seizures stop on their own, certain circumstances require immediate medical attention.

Emergency help should be sought if a seizure lasts longer than five minutes, another seizure begins immediately afterward or the person’s breathing or consciousness does not return after the seizure ends.

Immediate medical attention also is recommended when a seizure occurs in someone who is pregnant or has diabetes, when the person has a high fever or is injured during the seizure, or when seizures continue despite taking anti-seizure medication.

Anyone experiencing a seizure for the first time should seek medical evaluation.

Perhaps most importantly, people should remember that seizures do not all look alike. A few seconds of unexplained staring or confusion can be just as much a symptom of

abnormal brain activity as the convulsions most people associate with epilepsy.

Recognizing those less obvious signs can help people with recurring episodes get the medical evaluation and treatment they need. ■