Petit mal seizure - also known as absence seizure - is a type of seizure that most often occurs in children. An abnormal electrical discharge in the brain causes seizures. Other types of seizures include grand mal seizure and temporal lobe seizure.

Usually, a petit mal seizure involves only a brief, sudden lapse of conscious activity. Each seizure lasts only seconds or minutes, but hundreds may occur each day. During a petit mal seizure, small jerks sometimes occur involving the facial muscles, jaw or hands. A person who experiences a petit mal seizure can usually resume normal activities immediately after the seizure ends.

Petit mal seizures often affect people younger than 20, and children between the ages of 6 and 12 are most likely to have them. This type of seizure can run in families. Most children with petit mal seizures have an otherwise normal neurologic system. Many can expect to outgrow the disorder. Children who were young when the seizures first started, who have no other neurologic problems and who have seizures well controlled by medications are most likely to outgrow their seizures. In about half of children with petit mal seizures, the seizures will progress to grand mal seizures.

Repeated seizures characterize a seizure disorder known as epilepsy. Only 3 percent of people who have seizures will develop epilepsy. Less than 5 percent of children with seizure disorders have petit mal seizures. Some people with petit mal seizures may have other types of seizures, though most people have only one type of seizure.

Signs and symptoms

In a typical petit mal seizure, a brief, sudden absence of consciousness may occur. There may not be any movement at all, only what appears to be staring. In other cases, a seizure may cause lip smacking, fluttering eyelids, chewing or hand movements. Petit mal seizures last only a few seconds. Full recovery is almost instant. Afterward, there is no confusion, but also no memory of the incident.

Petit mal seizures may occur for weeks or months before an adult notices them, because they're so brief. Also, they usually occur when a child is sitting quietly and seldom during physical activity.

Because these seizures come and go so quickly, a noticeable decline in a child's learning ability may be the first sign of this disorder. Teachers also may comment about a child's inability to pay attention.

• Epilepsy

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