Absence seizureSeizure - petit mal; Seizure - absence; Petit mal seizure; Epilepsy - absence seizure
An absence seizure is the term for a type of seizure involving staring spells. This type of seizure is a brief (usually less than 15 seconds) disturbance of brain function due to abnormal electrical activity in the brain.
Absence seizures occur most often in people under age 20, usually in children ages 6 to 12.
In some cases, the seizures are triggered by flashing lights or when the person breathes faster and more deeply than usual (hyperventilates).
Generalized tonic-clonic seizures
Generalized tonic-clonic seizure is 1 type of seizure that involves the entire body. It is also called grand mal seizure. The terms seizure, convul...
Uncontrollable movements include many types of movements that you cannot control. They can affect the arms, legs, face, neck, or other parts of the ...
Most absence seizures last only a few seconds. They often involve staring episodes. The episodes may:
- Occur many times a day
- Occur for weeks to months before being noticed
- Interfere with school and learning
- Be mistaken for lack of attention, daydreaming or other misbehavior
Unexplained difficulties in school and learning difficulties may be the first sign of absence seizures.
During the seizure, the person may:
- Stop walking and start again a few seconds later
- Stop talking in mid-sentence and start again a few seconds later
The person usually does not fall during the seizure.
Right after the seizure, the person is usually:
- Wide awake
- Thinking clearly
- Unaware of the seizure
Specific symptoms of typical absence seizures may include:
- Changes in muscle activity, such as no movement, hand fumbling , fluttering eyelids, lip smacking, chewing
- Changes in alertness (consciousness) , such as staring episodes, lack of awareness of surroundings, sudden halt in movement, talking, and other awake activities
Some absence seizures begin slower and last longer. These are called atypical absence seizures. Symptoms are similar to regular absence seizures, but muscle activity changes may be more noticeable.
Exams and Tests
The doctor will perform a physical exam. This will include a detailed look at the brain and nervous system.
An EEG (electroencephalogram) will be done to check the electrical activity in the brain. People with seizures often have abnormal electrical activity seen on this test. In some cases, the test shows the area in the brain where the seizures start. The brain may appear normal after a seizure or between seizures.
An electroencephalogram is a test to measure the electrical activity of the brain.
Blood tests may also be ordered to check for other health problems that may be causing the seizures.
A head computed tomography (CT) scan uses many x-rays to create pictures of the head, including the skull, brain, eye sockets, and sinuses.
A head MRI (magnetic resonance imaging) is an imaging test that uses powerful magnets and radio waves to create pictures of the brain and surrounding...
Epilepsy is a brain disorder in which a person has repeated seizures over time. Seizures are episodes of uncontrolled and abnormal firing of brain c...
You have epilepsy. People with epilepsy have seizures. A seizure is a sudden brief change in the electrical and chemical activity in the brain. Th...
Abou-Khalil BW, Gallagher MJ, Macdonald RL. Epilepsies. In: Daroff RB, Jankovic J, Mazziotta JC, Pomeroy SK, eds. Bradley's Neurology in Clinical Practice . 7th ed. Philadelphia, PA: Elsevier; 2016:chap 101.
Marcdante KJ, Kliegman RM. Seizures (paroxysmal disorders). In: Marcdante KJ, Kliegman RM, eds. Nelson Essentials of Pediatrics . 7th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 181.
Wiebe S. The epilepsies. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 403.
Central nervous system - illustration
The central nervous system is comprised of the brain and spinal cord. The peripheral nervous system includes all peripheral nerves.
Central nervous system
Review Date: 2/27/2016
Reviewed By: Amit M. Shelat, DO, FACP, Attending Neurologist and Assistant Professor of Clinical Neurology, SUNY Stony Brook, School of Medicine, Stony Brook, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.