Types Of Epileptic Seizures
Types Of Epileptic Seizures
Seizures are the most common symptoms of epilepsy. Seizures are a result of disruption in the normal electrical activity in the brain. There are different types of epileptic seizures and they are categorized according to their symptoms and from the region in the brain they arise from.
The categorization of the types of epileptic seizures was first done by the ILAE (International League Against Epilepsy) in the early 1980s. There are 2 broad categories of epileptic seizures and these are generalized seizures and partial seizures. A third category of epileptic seizures is referred to as unclassified seizures.
Generalized seizures are the types of epileptic seizures that arise from both the hemispheres of the brain at the same time. Because of the involvement of the 2 hemispheres of the brain, an individual suffering from a generalized seizure will lose consciousness. Generalized seizures are further sub-divided into 6 types; tonic clonic seizures, myoclonic seizures, clonic seizures, atonic seizures and absence seizures.
Tonic clonic seizures are also known as grand mal seizures and are one of the most common types of epileptic seizures. In the tonic phase of the seizure, muscles become stiff due to contraction and there may be other symptoms such as urinary incontinence and tongue biting. The individual may stop breathing. The tonic phase is followed by the clonic phase with jerking of limbs due to rhythmic contractions of the muscles.
Myoclonic seizures are very short and will typically last only seconds. They are characterized by sporadical jerking of the limbs caused by a muscle contraction.
Clonic seizures involve what is called myoclonus, the sudden and brief jerking of a group of muscles.
Atonic seizures are also referred to as akinetic seizures, astatic seizures or informally as drop attacks as they involve loss of muscle tone which causes an individual to fall. These may be dangerous if a person falls and hits their head hard.
Absence seizures are also known as petit mal seizures. These types of epileptic seizures only last a short while and involve loss of consciousness. They usually have no lasting effects and may go unnoticed. They very commonly occur in children.
Partial seizures, also known as focal seizures, are the types of epileptic seizures that start in one part of the brain. The seizures may however spread to other parts. They are further divided into simple partial seizures or complex partial seizures depending on whether or not consciousness is affected during the seizure. Simple partial seizures do not affect consciousness while complex partial seizures do and may sometimes lead to loss of consciousness. Sometimes, a partial seizure may evolve and become a generalized seizure.
Though rare, some people may experience both types of epileptic seizures (generalized and partial seizures).
Though most of our articles are generalized, we hope our attempt to define epilepsy can help those reading the information further understand the problem of epilepsy and how to deal with it.