What is a seizure?

A seizure is a sudden surge of abnormal electrical activity in the brain that disrupts normal brain activity.

Not all seizures look or feel the same. There are different types of seizures and three stages of a seizure. Each type and stage can have varying signs and symptoms. The image that generally comes to mind when someone pictures a seizure is uncontrollable jerking movements — a classic symptom associated with tonic-clonic (grand mal) seizures. Yet, there are other observable signs of seizures. Some are quite obvious while others can be difficult to detect.

There is a broad range of potential factors that can trigger seizures in children and adolescents. If your child has reflex epilepsy, his or her seizures are consistently triggered by something specific. Triggers are unique to each individual and may include:

  • Missing doses of anti-seizure medications
  • Health concerns, such as illness, fever, stress, lack of sleep, poor nutrition, dehydration or hormonal changes
  • Flashing or flickering lights, busy patterns, or even certain colors
  • Certain foods, medications, drugs, alcohol or smells
  • Certain strong smells or fumes
  • Environmental factors, such as lightness, darkness, weather, air pressure or temperature
If your child has specific seizure triggers, it's important to know what they are so he or she can learn to avoid them.
If your child has one seizure, it may or may not mean that your child has epilepsy. If your child has one seizure that occurs as a direct result of a single event, such as illness, injury or trauma, this is a provoked seizure, which is not necessarily indicative of epilepsy.
However, your child may be diagnosed with epilepsy if he or she has two or more unprovoked seizures. Our specialists at the Pediatric Epilepsy Center have the expertise and sophisticated technology to conduct a thorough medical assessment and provide a definitive diagnosis. That enables us to develop the best treatment plan for your child and your family.

Types of Seizures

Seizures are classified in two major categories based on the origin of the abnormal electrical activity in the brain:

  • Primary generalized seizures start with widespread electrical activity on both sides of the brain.
  • Partial (focal) seizures begin with electrical activity confined to one side of the brain.

Within these two categories, there are dozens of types of seizures. Each type is associated with a combination of symptoms. It is important to get an expert medical assessment to determine which type of seizure your child is having and determine the most effective treatment for that specific type of seizure.

Some seizures and epilepsy syndromes cannot be simply classified in these two categories. Sometimes a seizure starts on one side of the brain and spreads to the other side. This is called a secondarily generalized seizure (SGS). Additionally, it is possible to have primary generalized seizures with occasional partial (focal) seizures. This is called symptomatic generalized epilepsy (SGE).

Absence Seizures

If your child is experiencing absence seizures, also known as petit mal seizures, he or she may seem to “space out” or stare blankly. It’s possible that your child’s eyes may roll. This type of staring is different from a child mesmerized by the television, for example. It occurs with no apparent reason and may happen suddenly. If your child has absence seizures, there’s a good chance he or she may lose awareness during the seizure and may not remember it afterward. It’s also possible that your child will have subtle body movement during the seizure — but not the classic jerking spasms associated with other types of seizures. 

Atonic Seizures

Atonic seizures may involve a sudden loss of muscle tone, a head drop or leg weakening. If your child has an atonic seizure, he or she may suddenly collapse or drop objects. Atonic seizures are also called drop attacksdrop seizures and akinetic epileptic drop attacks

Clonic Seizures

Characterized by jerking muscle movements and spasms, clonic seizures involve movements that are most often rhythmic rather than chaotic. The affected muscles are usually in the face, neck or arms. Clonic seizures may last for several minutes. 

Tonic-Clonic Seizures

Tonic-clonic seizures, also known as grand mal seizures, are characterized by classic symptoms that tend to be most commonly associated with seizures: loss of consciousness, body stiffening and jerking or shaking movements. Symptoms may also include loss of bladder or bowel control. 

Tonic Seizures

Tonic seizures cause the body to stiffen. If your child has a tonic seizure, he or she may fall or collapse. The stiffening most often affects muscles in the back, arm or leg. 

Myoclonic Seizures

Characterized by uncontrollable jerking movement, myoclonic seizures most often affect the arms, legs or both. Myoclonic seizures are usually brief, lasting for only a second or two. 

Partial seizures, also known as focal seizures, are classified as one of two types:

  • Simple partial seizures, also called simple focal seizures
  • Complex partial seizures, also called psychomotor seizures

Recurrent partial (focal) seizures are sometimes also referred to as one of four classifications based on the area of the brain where seizure activity occurs:

  • Frontal lobe epilepsy
  • Occipital lobe epilepsy
  • Parietal lobe epilepsy
  • Temporal lobe epilepsy

The location of the seizure activity is closely associated with the type of seizures that occur and the severity of the impact on the child. For example, gelastic epilepsy is associated with hypothalamic hamartoma, a benign tumor or lesion located in or near the hypothalamus. With gelastic seizures, most commonly characterized by uncontrollable laughing spells, activity generally occurs around the hypothalamus in the frontal or temporal lobe.

Simple partial seizures (Simple focal seizures)

Some simple partial seizures only include the aura stage, which is the first of three stages often seen with other types of seizures. If your child has a simple partial seizure, he or she will remain aware and conscious, and will likely retain all memory of what happened. The seizure may alter your child’s emotions or alter sensory perception, changing the way things smell, taste, look, feel or sound. He or she may also experience involuntary jerking of an arm, leg or other body part and may experience spontaneous sensory symptoms, like dizziness, tingling or seeing flashing lights.

Complex partial seizures (Psychomotor seizures)

Complex partial seizures alter consciousness or responsiveness. If your child has this type of seizure, he or she may appear to move without purpose or stare into space. Some of the movements often associated with complex partial seizures include abnormal or continuous swallowing, hand rubbing, chewing, or repetitive motion, like walking in a circle or moving the legs as if riding a bicycle.

Stages of a Seizure

Seizures generally have three stages, each with different symptoms. Symptoms also vary with different types of seizures.

The aura stage happens before the actual seizure begins. Children who have seizures often learn to recognize warning signs at this stage. Although people experience auras differently, symptoms can include:

  • Abnormal sensations
  • Altered taste, smell or sound perception
  • Déjà vu
  • Dizziness
  • Headache
  • Lightheadedness
  • Nausea
  • Numbness
  • Strong or distorted emotions, such as fear or panic

The ictus stage is the seizure itself. Signs and symptoms at this stage will vary depending on the type of seizure your child experiences.

There are generalized seizures, including tonic-clonic (grand mal), tonic, clonic, absence (petite mal), myoclonic and atonic seizures.

There are also partial (focal) seizures, including simple partial (simple focal) and complex partial (psychomotor) seizures.

This is the post-seizure stage. As your child’s body begins to relax and recover from the seizure, some aftereffects may set in. This stage may vary in length from a minute or two up to a half hour or even longer. Symptoms of the post-ictal stage may include:

  • Confusion
  • Headache
  • Fatigue
  • Loss of consciousness
  • Loss of bladder or bowel control
  • Numbness
  • Partial (temporary) paralysis