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Seizure Types

There are several different types of seizures, seizure disorders or epilepsy types. Most fall under two main categories:

 

1. Generalized Seizures

Generalized Seizures occur when there is widespread seizure activity in the left and right hemispheres of the brain. The most common forms of generalized seizures are:

  • absence seizures (formerly known as petit mal)
  • tonic-clonic or convulsive seizures (formerly known as grand mal)

 

Some people experience a sensory or psychic phenomena (previously known as an aura) – a partial seizure preceding a generalized seizure – which is often seen as a warning sign. A sensory or psychic phenomena may be emotional (e.g. fear, anxiety), physical (e.g. dizziness, nausea), or sensory (e.g. tingling or crawling sensation on the skin, spots or colours before the eyes, strange tastes or smells).

 

 

ABSENCE SEIZURES

In an absence seizure, epileptic activity occurs throughout the entire brain. It is a milder type of activity that causes unconsciousness without convulsions. After the seizure, the person has no memory of it.

 

An absence seizure begins and ends abruptly and without warning. It consists of a period of unconsciousness with a blank stare. It may look like the person is daydreaming. The person may lose muscle control and make repetitive movements such as:

  • chewing movements
  • rapid breathing
  • rhythmic blinking
  • slight movements or tugging at clothing

 

Absence seizures are brief, usually lasting only two to ten seconds. There is no confusion after the seizure, and the person can usually resume full activity immediately.

 

First Aid for Absence Seizures

After the seizure, explain to the person that s/he just had a seizure and inform him/her of anything s/he missed.

 

 

TONIC-CLONIC SEIZURES

During a generalized tonic-clonic (formerly grand mal) seizure, electric discharges instantaneously involve the entire brain. The person loses consciousness right from the beginning of the seizure.

 

The person will usually emit a short, loud cry as the muscles in the chest contract and the air rushes between the vocal cords, making a sound. This cry does not indicate pain. The muscles will stiffen (tonic phase), causing him/her to fall to the floor. Increased pressure on the bladder and bowel may cause wetting (urinary incontinence) or soiling (fecal incontinence). The person may bite their tongue, which may cause bleeding.

 

The extremities will then jerk and twitch rhythmically (clonic phase). Saliva that is not swallowed during the seizure may froth at the mouth. Breathing may be irregular as the respiratory muscles may be affected. The person will regain consciousness slowly.

 

A tonic-clonic seizure usually lasts one to three minutes, but may last up to five minutes. If seizures last more than five minutes, or occur one after another without recovery between seizures, the individual may be experiencing Status Epilepticus. This continuous seizure state is a life-threatening medical emergency and requires immediate medical help.

 

The period after the seizure is referred to as the post-ictal state. During this time, the person will need to rest. It may be difficult to wake him/her or get any response from him/her during this time. After a seizure, the person may feel fatigue, confusion, and disorientation, which may last from five minutes to several hours or even days. Rarely, this disorientation may last up to two weeks.

 

The person may fall asleep, or gradually become less confused until full consciousness is regained. S/he may have a headache once s/he regains consciousness. There is no evidence that tonic-clonic seizures cause mental retardation or brain damage.

 

 

First Aid for Tonic-Clonic Seizures

1. Stay Calm

Most often, a seizure will run its course and end naturally within a few minutes.

 

2. Time It

If the seizure lasts more than 5 minutes or repeats without full recovery between seizures, call 911. Call 911 if the person is pregnant, has diabetes, is injured from the seizure or if the seizure occurs in water. Call 911 if you are not sure the person has epilepsy or a seizure disorder.

 

3. Protect From Injury

Move sharp objects out of the way. If the person falls to the ground, roll them onto their side and place something soft under their head. When the seizure ends, provide reassurance and stay with the person if they are confused.

 

Do not restrain the person.

 

Never put anything in the person's mouth.

 

 

ATONIC AND MYOCLONIC SEIZURES

Other types of generalized seizures include atonic and myoclonic seizures.

 

An atonic seizure is sometimes called a "drop attack." The seizure involves a sudden loss of muscle tone. This can result in the person falling down or almost falling down, dropping objects, or nodding the head involuntarily. Typically, these seizures last for a few seconds. There tends to be no warning so the seizures can be dangerous because of injury.

 

A myoclonic seizure results in a sudden jerk of part of the body such as the arm or leg. The person may fall over. The seizure is very brief. People who do not have epilepsy sometimes experience a sudden jerk of the body when they are falling asleep. This is common and is known as benign nocturnal myoclonus. It is not an epilepsy-related seizure.

 

 

2. Focal Seizures

Focal Seizures (previusly known as partial seizures) occur when seizure activity is limited to a part of one brain hemisphere. There is a site, or a focus, in the brain where the seizure begins. The most common forms of focal seizures are:

  • simple partial seizures (sometimes referred to as an aura)
  • complex partial seizures

 

 

SIMPLE PARTIAL SEIZURES

Focal seizures originate in one area of the brain, usually the cortex or limbic system. In some people, focal seizures can lead to tonic-clonic convulsions.

 

The person having a focal seizure will not lose consciousness during the seizure, but will be unable to control various body movements. People experiencing a simple partial seizure can talk and answer questions. They will remember what happened during the seizure.

 

Simple partial seizures take different forms in different people. The person’s sense may be distorted causing him/her to see, hear, or smell things that are not real. S/he may also experience unusual feelings. All these symptoms are further classified into four categories:

 

Autonomic Seizures

These seizures are accompanied by autonomic symptoms or signs, such as abdominal discomfort or nausea which may rise into the throat (epigastric rising), stomach pain, the rumbling sounds of gas moving in the intestines (borborygmi), belching, flatulence, and vomiting. This has sometimes been referred to as abdominal epilepsy. Other symptoms may include pallor, flushing, sweating, hair standing on end (piloerection), dilation of the pupils, alterations in heart rate and respiration, and urination. A few people may experience sexual arousal, penile erection, and orgasm.

 

Emotional and Other

Simple partial seizures which arise in or near the temporal lobes often take the form of an odd experience. One may see or hear things that are not there. One feels emotions, often fear, but sometimes sadness, anger, or joy. There may be a bad smell or a bad taste, a funny feeling in the pit of the stomach or a choking sensation. These seizures are sometimes called simple partial seizures of temporal lobe origin or temporal lobe auras.

 

Motor

Other simple partial seizures include convulsive (clonic, jerking) movements. Jerking typically begins in one area of the body — the face, arm, leg, or trunk — and may spread to other parts of the body. These seizures are sometimes called Jacksonian motor seizures; their spread is called a Jacksonian march. It cannot be stopped.

 

Sensory Seizures

Some simple partial seizures consist of a sensory experience. The person may see lights, hear a buzzing sound, or feel tingling or numbness in a part of the body. These seizures are sometimes called Jacksonian sensory seizures.

 

Simple partial seizures usually last two to 10 seconds, although they may last longer. If there are no convulsions, they may not be obvious to the onlooker.

 

 

WHAT ARE AURAS?

For some people, the first symptom of a seizure may be an aura. An aura is a form of simple partial seizure and is experienced as peculiar sensory or motor phenomenon.

Common aura descriptions:

  • butterflies in the stomach
  • flashes of light
  • odd noises (e.g. buzzing in the ear)
  • strange smells (e.g. burnt toast, rotten eggs)
  • a powerful emotion
  • dizziness

 

When these occur, they are a good indication that a generalized seizure (widespread seizure activity in both hemispheres of the brain) is about to occur. People who experience auras can use them as a warning signal.

 

Children and Auras

It is helpful to teach the child about auras to help the child determine if s/he experiences them. When the child experiences an aura, s/he can take quick precautions to ensure safety and avoid potentially harmful situations.

 

 

 

First Aid for Simple Partial Seizures

 

Comfort and reassure the person if s/he feels confused following the simple partial seizure.

 

 

COMPLEX PARTIAL SEIZURES

(formerly Psychomotor or Temporal Lobe Seizures)

 

A complex partial seizure occurs when epileptic activity spreads to both temporal lobes in the brain. A complex partial seizure often occurs after a simple partial seizure originating in the temporal lobe. Children experience the most complex partial seizures with varying degrees of altered levels of consciousness. Some lead to tonic-clonic seizures.

 

A complex partial seizure does not involve convulsions, but it impairs consciousness. During the seizure, the person will no longer respond to questions. Someone experiencing a complex partial seizure may become frightened and try to run and struggle. Following the seizure, there will be no memory of it.

 

During a complex partial seizure, the person stops and has a blank look or empty stare. S/he will appear unaware of the environment and may seem dazed. The seizure may progress to manifest any of the following “inappropriate” automatic behaviours:

  • chewing movements
  • uncoordinated activity
  • meaningless bits of behaviour that appear random and clumsy including
      • picking at their clothes or trying to remove them
      • walking about aimlessly
      • picking up things
      • mumbling.

 

A complex partial seizure usually lasts about two to four minutes. After the seizure, there is usually a period of confusion lasting longer. Once the pattern of seizures is established, it will usually be repeated with each subsequent seizure. Complex partial seizures sometimes resist anticonvulsant medication.

 

 

First Aid for Complex Partial Seizures

 

  • Supervise the person and gently guide him/her away from potential danger or to sit down.

 

  • Do not restrain the person since s/he may instinctively lash out or become highly agitated.

 

  • Comfort the person during and following the seizure.

 

 

If you have epilepsy or suspect you had a seizure-like episode, learning the names and terms for your symptoms can help you describe it accurately to others. Health care providers in particular rely on this information to make a correct diagnosis of your condition.

 

Reprinted in part from Epilepsy Ontario.