Seizure: Types, Symptoms & Causes

Instructor: Aileen Staller
Seizures are symptoms of brain injury, disease, or abnormality affecting the brain's physical, electrical, or chemical activity. In this lesson, we'll discuss potential causes, symptoms, and first aid for the person having the seizure.

What Is a Seizure?

Imagine being in a room that is hit by lightning - the wires spark and sputter, sending smoke and flames into the room, the electrical equipment, and the wires themselves. This describes a seizure, also known as a convulsion or fit. In this case, the head is the room, the brain is the electrical equipment, and the brain cells (neurons), which send information throughout the brain, represent the wiring. The abnormal or excess discharge of electrical activity in the brain causes a seizure, resulting in physical or behavioral changes.

Seizures: Types and Symptoms

Seizures vary in presentation, from loss of consciousness and total body shaking to staring spells or smells noticeable only to the person experiencing the seizure. Various types of seizures are listed below along with descriptions of each.

Name Description
Complex seizure Loss of awareness
Partial seizures No changes in consciousness or awareness
Tonic-clonic seizures (AKA grand mal or complex generalized seizures) Changes in level of consciousness (unresponsiveness) or loss of consciousness, usually falling to the floor;

Body shaking;

After-effects, such as drowsiness, lethargy, deep sleep, and temporary paralysis on one side, are also common
Partial complex seizures Shaking and abnormal movements in certain areas of the body;

Some changes in awareness but usually not unresponsiveness
Simple complex seizures Shaking and abnormal movements without changes in awareness
Myoclonic seizures Shaking movements in a single muscle group but no loss of awareness
Absence seizures Momentary lack of awareness of the surroundings;

Automatic movements like lip smacking, blinking, eye rolling, or finger snapping;

No loss of consciousness;

People may continue performing a physical task (writing, stirring, etc.) during the seizure
Febrile seizures Seizures of any type that present in children with a high fever

Additional Symptom Details

As previously mentioned, seizures may present with a decrease or loss of consciousness (called complex seizures) or no change in consciousness or awareness (simple/partial seizures).

Individuals who present with a complex generalized seizure (tonic-clonic) have loss of bowel and bladder control and slowness of breathing. Increased salivation and frothing at the mouth may also be present along with teeth clenching and gurgling sounds. When the seizure passes, usually in seconds to minutes, the person may not remember anything about the episode or may be very tired and confused. Following the seizure activity, the person may exhibit weakness or paralysis on one side of the body, resembling what is seen with a stroke; this is called Todd's palsy and generally resolves in a short time period after the seizure.

Simple partial seizures (no loss of consciousness) are associated with lip smacking, staring spells, unusual smells, behavior changes, grunting/crying out, and rhythmic jerking of a single muscle group or extremity. Abnormal eye movements, picking movements, mood changes, and behavior changes may also be seen.

Seizure Causes

Seizures are usually a symptom of an underlying condition and can be caused by the following:

  1. Irritation to the brain (bleeding, head injury, infection)
  2. Relatively quick decrease in blood sodium levels (usually associated with drinking unusually large quantities of plain water over a short time)
  3. Low or high blood sugar (glucose) levels
  4. Brain tumor (relatively rare)
  5. Drugs (use of drugs or withdrawal)
  6. Stroke
  7. Complication of pregnancy
  8. Buildup of toxins (kidney failure, liver dysfunction)
  9. Alcohol use or withdrawal

First Aid for Seizures

The major objective is to protect the person from additional harm. Guide them slowly to the floor, away from furniture or other objects that may be in the way of the shaking, flailing movements. Place a rolled up piece of clothing or other soft object under the head for protection during the shaking movements. Loosen any tight clothing in the neck area.

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