Epilepsy is a seizure disorder. A seizure is an event that involves loss of consciousness and motor (muscular) control. A person with a seizure disorder often experiences repetitive muscle jerking called convulsions. The condition is caused by a sudden change in electrical activity in the brain.
Epilepsy is a disorder of recurrent seizures that are neural in origin. Partial seizures are usually due to a structural cerebrocortical lesion and may be simple or complex. Brain injuries may alter inherent neuronal properties and neuronal circuits and lead to recurrent excitatory activity. Potentiation of excitatory synapses and depression of inhibitory synapses are probable critical events in epileptogenesis. The pathogenic factors underlying primary or idiopathic generalized seizures are not as well understood. A more diffuse or multifocal state of neuronal excitability may be the result of early congenital events that are magnified over time. The progression of subclinical neuronal excitatory activity to a clinical seizure may relate directly to the phenomenon of cortical plasticity.