Woman with a magnifying glassThe form, intensity, and duration of seizures are related to the number and type of brain cells affected. There are two broad types of seizures: generalized and partial. They range from convulsions to momentary lapses of attention.

When large areas of the brain are involved, the seizures are termed “generalized” and affect both consciousness and motor function from the outset. When a smaller portion of the brain is affected, the seizures are called “partial,” and initially have specific effects depending on the part of brain involved. It is not uncommon for persons to experience both seizure types.

Types of seizures

Tonic-Clonic (“Grand Mal”)

The most common generalized seizure is tonic-clonic, formerly known as “grand mal.” Fortunately, medication is frequently successful in controlling this type of seizure.

A tonic-clonic seizure is characterized by a convulsion in which the person’s body stiffens, arms flex, legs, head and neck extend, and the jaws clamp shut; this is the “tonic” phase. The person falls to the ground, often uttering a hoarse cry, and temporarily loses consciousness for a few minutes. During this time, breathing appears difficult, the body jerks, saliva may accumulate in the mouth, and the bladder may empty. This is the “clonic” phase. Eventually, the jerking motions diminish and the person regains consciousness, somewhat disoriented and fatigued from the intense muscular activity.

Absence (“Petit Mal”)

A generalized seizure, especially prevalent in children four to fourteen years old, is absence, formerly known as petit mal. The absence seizure is considerably milder in form than the tonic-clonic and, in fact, often passes for daydreaming. Thus, the elementary school teacher often notices the disorder before anyone else is aware of it.

The absence seizure is most commonly characterized by a brief lapse of consciousness with staring, eye blinking, or upward rolling of the eyes. It is not uncommon for a child to have 50 to 100 absence seizures a day. Many children outgrow this epilepsy at puberty and never have another seizure, but some develop other types of seizures.

Medication often can reduce the number of absence seizures or eliminate them altogether.

Complex-Partial (“Temporal Lobe” or “Psychomotor”)

The most common partial seizure is what is now termed complex-partial and formerly was known as temporal lobe or psychomotor. The complex-partial seizure consists of three brief phases: The person stops ongoing activity and assumes a dazed and staring expression. Then a pattern of repititous, automatic, purposeless behavior begins and typically lasts a few minutes. Such behavior may include lip smacking, picking at clothes, buttoning and unbuttoning clothes or finger pulling. As the person returns to consciousness, a short period of disorientation and confusion occurs.

The Aura

Seizure activity sometimes begins with a brief sensation in the stomach or head, such as a sinking or rising feeling, a buzzing sound, an unpleasant odor, or spots before the eyes — an “aura.” Those persons who can train themselves to recognize the start of seizure activity before it spreads to other parts of the brain can use it as a warning to take protective measures to prevent possible injury during the seizure itself.