Epilepsy

Epilepsy is a common chronic neurological disorder that is characterized by recurrent unprovoked seizures.These seizures are transient signs and/or symptoms due to abnormal, excessive or synchronous neuronal activity in the brain. About 50 million people worldwide have epilepsy at any one time.Epilepsy should not be understood as a single disorder, but rather as a group of syndromes with vastly divergent symptoms but all involving episodic abnormal electrical activity in the brain.

  Subscribe in a reader

Epilepsies are classified in six ways:

1. By their first cause (or etiology).
2. By the observable manifestations of the seizures, known as semiology.
3. By the location in the brain where the seizures originate.
4. As a part of discrete, identifiable medical syndromes.
5. By the event that triggers the seizures, as in primary reading epilepsy or musicogenic epilepsy.

In 1981, the International League Against Epilepsy (ILAE) proposed a classification scheme for individual seizures that remains in common use. This classification is based on observation (clinical and EEG) rather than the underlying pathophysiology or anatomy and is outlined later on in this article. In 1989, the ILAE proposed a classification scheme for epilepsies and epileptic syndromes. This can be broadly described as a two-axis scheme having the cause on one axis and the extent of localisation within the brain on the other. Since 1997, the ILAE have been working on a new scheme that has five axes: ictal phenomenon, seizure type, syndrome, etiology and impairment.

When the neuron becomes excited it passes an electrical signal along its thin biological wire called an axon for communicating with other neurons in the brain. Other neurons either can be excited or inhibited by the signal. When too many neurons become excited all at once then a seizure can result. So seizure is like an electrical storm in the brain. During this abnormal electrical storm the involved parts of the brain cannot perform their normal tasks and people experienced sudden alterations in movements, sensations, awareness or behavior. a seizure typically goes on for few seconds to a few minutes .the end of the seizure is a transition back to individuals normal state .because the word ictal is Latin for seizure the recovery period is referred to as the post-ictal. Which can last from seconds to hours person's level of awareness gradually improves during the post. Ictal period.