What is a seizure?
Epileptic seizures are caused by sudden episodes of electrical activity in the brain. They can change physical activities or mental behavior. A seizure is a symptom of an underlying disorder. It is a sign that something in the brain is not working as it should.1
The causes of seizures in epilepsy may be related to a brain formation or injury. This is sometimes the case with Lennox-Gastaut syndrome (LGS), but often the cause is unknown.
Seizures associated with LGS
Tonic, atonic, and atypical absence seizures are among the most common in LGS, although tonic-clonic, myoclonic, and other seizure types may occur.2
The types of seizures associated with LGS include the following:
- Tonic – stiffening of muscles lasting a few seconds up to a minute. Generally, muscles tighten, eyes roll back, and pupils dilate.3 Breathing may temporarily stop and heart rate can increase.3 Tonic seizures usually happen during sleep but a patient who is standing can be thrown to the ground (a “drop attack”).2,3
- Atonic – brief loss of muscle tone, causing falls (also known as "drop attacks" or "drop seizures").2 They’re usually very brief, lasting only a few seconds.3
- Tonic-clonic – begins with stiffening of the limbs (the tonic phase), followed by jerking of the limbs and face (the clonic phase).4
- Atypical Absence – staring spells lasting generally 5-30 seconds, with gradual onset and termination.2,3 May include staring, pauses in activity and a lack of response.3
- Myoclonic – sudden muscle jerks lasting for many seconds up to a minute. They usually happen the same way on both sides of the body.
- Clonic – a pattern of jerking movements.
- Partial – limited to a specific area of the brain; sometimes consciousness may be lost.
Seizures in children versus adults
As patients reach adulthood, their seizure types may evolve.4
NEXT: Living With Seizures
| References: |
| 1 |
Epilepsy. Basics. Center for Disease Control and Prevention Web site http://www.cdc.gov/epilepsy/basics/faqs.htm Accessed April 7, 2011 |
| 2 |
Arzimanoglou A, French J, Blume WT, et al. Lennox-Gastaut syndrome: a consensus approach on diagnosis, assessment, management, and trial methodology. Lancet Neurol. 2009;8:82-93. |
| 3 |
Crumrine PK. Lennox-Gastaut syndrome. J Child Neurol. 2002;17(suppl 1):S70-75. |
| 4 |
Benbadis SR. Epileptic seizures and syndromes. Neurol Clin. 2001;19(2):251-270. |