Epilepsy is a nervous system disorder that causes seizures. Seizures are temporary changes in brain activity. Doctors categorize and treat different types of epilepsy based on the kind of seizure they cause. Absence seizures, or petit mal seizures, are brief, usually less than 15 seconds, and they have symptoms that may be barely noticeable.
Staring-spell seizures are often lumped together in public awareness under the heading of "petit mal" epilepsy. Petit mal is French for "minor illness," reflecting their more subtle appearance. However, using current terminology, there are two main kinds of staring-spell attacks--absence seizures and partial-complex seizures.
A grand mal seizure causes a loss of consciousness and violent muscle contractions. It's the type of seizure most people picture when they think about seizures. A grand mal seizure — also known as a generalized tonic-clonic seizure — is caused by abnormal electrical activity throughout the brain. Usually, a grand mal seizure is caused by epilepsy.