An epileptic seizure is defined as a transient symptom of "abnormal excessive or synchronous neuronal activity in the brain". The outward effect can be as dramatic as a wild thrashing movement (tonic-clonic seizure) or as mild as a brief loss of awareness (absence seizure). Non-epileptic seizures mimic epileptic seizures but have different causes.
Generalized seizures -- involve much more or all of the brain. They can be:
-Absence seizures -- Symptoms may include staring and brief loss of consciousness.
-Myoclonic seizures -- Symptoms may include jerking or twitching of the limbs on both sides of the body.
-Tonic-clonic seizures -- Symptoms may include loss of consciousness, shaking or jerking of the body, and loss of bladder control... These seizures can last from 5 - 20 minutes.
Partial seizures -- involve a part of the brain. They can be:
-Simple partial seizures -- Symptoms may include involuntary twitching of the muscles or arms and legs; changes in vision; vertigo; and experiencing unusual tastes or smells. The person does not lose consciousness.
-Complex partial seizures -- Symptoms may be similar to those of partial seizures, but the person does lose awareness for a time.
There are many different types of seizures... The kind of seizure a person has depends on which part and how much of the brain is affected by the electrical disturbance that produces seizures. Experts divide seizures into generalized seizures (absence, atonic, tonic-clonic, myoclonic), partial (simple and complex) seizures, gelastic seizures, dacrystic seizures, non-epileptic seizures and status epilepticus.
Seizures can last from just a few seconds up to a few minutes. The greatest majority of seizures stop on their own. However, in rare cases seizures can last hours, requiring urgent medical attention. If you notice a person having a seizure, protect the person from harm until he or she regains awareness and control.
Shaking of the body, either mild or violent, does not always occur with seizures. Some people who have seizures have symptoms before the seizure (auras) or briefly lose touch with their surroundings and appear to stare into space. Although the person is awake, he or she does not respond normally. Afterwards, the person does not remember the episode.
Febrile seizures are convulsions brought on by a fever in infants or small children. During a febrile seizure, a child often loses consciousness and shakes, moving limbs on both sides of the body... The majority of children with febrile seizures have rectal temperatures greater than 102 degrees Fahrenheit... Although they can be frightening to parents, the vast majority of febrile seizures are short and harmless.
Some people are susceptible to seizures caused by strobing, flickering, or flashing effects. This kind of seizure is sometimes referred to as a photoepileptic seizure because it is caused by pulses of light (hence the prefix "photo") interacting with the eye's light-receptive neurons and the body's central nervous system.
A person may have a seizure disorder (epilepsy) and require medications. Other factors such as hypoglycemia (low blood sugar), which is a diabetic reaction, may cause seizures. Meningitis or a head injury may also cause a seizure.
A small number of people will have only one seizure during their lifetime. A single seizure usually lasts less than 3 minutes and is not followed by a second seizure. Any normally healthy person can have a single seizure under certain conditions... But if you have a first-time seizure, you should be checked by your doctor.
Seizures happen when the electrical system of the brain malfunctions. Instead of discharging electrical energy in a controlled manner, the brain cells keep firing. The result may be a surge of energy through the brain, causing unconsciousness and contractions of the muscles.