According to the Merck Manual, approximately 2 percent of people in the United States have a seizure of no clear origin in their lifetime, but two-thirds of those people never have another seizure. A diagnosis of epilepsy requires two such incidents. Epilepsy occurs as a result of an electrical malfunction in the brain, causing seizures. There are several types of epilepsy, categorized by the types of seizures and symptoms the patient displays.
Aura
Sometimes a phenomenon called aura precedes a seizure. The patient might feel fearful or experience intense déjà vu, perceive non-existent smells or complain of tingling or numbness.
Altered Consciousness
Partial seizures, affecting just one distinct area of the brain, can alter consciousness. In simple partial seizures, patients might experience altered perception in vision, smells, feels, tastes and sounds. Patients might notice
tingling sensations, suffer dizziness, or hallucinate flashing lights, says the Mayo Clinic, but they remain at least partially aware of their surroundings.
Patients with complex partial seizures experience more profound alteration in consciousness. In the midst of a seizure, the patient might unknowingly perform repetitive motions such as walking in circles or rubbing the hands together. Patients lose awareness and often stare blankly, regardless of what happens around them.
Loss of Consciousness
Generalized seizures involving the entire brain cause the patient to lose consciousness. In the disorder known as typical absence epilepsy (also called petit mal), the patient stops and stares for 10 seconds to 30 seconds or so, with eyelids fluttering, says the Merck Manual. When consciousness returns, the patient doesn't realize he suffered a seizure, and continues as if nothing happened.
Patients with atonic seizures and tonic-clonic (or grand mal) seizures also lose consciousness during an episode.
Jerking
Myoclonic seizures involve jerking and twitching of the limbs while the patient is conscious. The jerking can affect both sides of the body (bilateral), or only one (unilateral). The Merck Manual describes these movements as brief and lightning-like.
Falls
In an atonic seizure, the patient loses consciousness and all muscle tone, abruptly pitching to the ground. With no warning of an episode, the falls can be quite dangerous.
Other
Tonic-clonic or grand mal seizures cause the stereotypical epilepsy symptoms of total loss of consciousness and body control, characterized by rapid contraction and relaxation of muscles in the limbs and trunk that cause the whole body to stiffen and jerk. Tonic-clonic seizures can also cause frothing at the mouth, loss of bladder and/or bowel control, and damage to the tongue.
