What Is Epilepsy|
The word "Epilepsy" is derived from a Greek word meaning "a condition of being overcome, seized, or attacked." People used to believe that the seizure was caused by a demon, and Epilepsy became known as a sacred disease. Epilepsy is not a disease. It is a sign or symptom of an underlying neurological disorder. People with epilepsy commonly suffer from a seizure - or an epileptic attack.
What Causes Epilepsy?
To understand how epilepsy arises, here briefly is an outline on how the brain functions.
The brain consists of millions of nerve cells, or neurones, and their supporting structure. Each neurone maintains itself in an electrically charged state. It receives electrical signals from other neurones, and passes them on to others. What actually happens is that a tiny quantity of a special neurotransmitter substance is released from the terminals of one neurone. This chemical excites an electrical response in the nuerone next in the chain, and so the signal moves onward.
All the functions of the brain, including feeling, seeing, thinking and moving muscles depend on electrical signals being passed from one neurone to the next, the message being modified as required. The normal brain is constantly generating electrical rhythms in an orderly way.
In epilepsy this order is disrupted by some neurone discharging signals inappropriately. There may be a kind of brief electrical "storm" arising from nuerones that are inherently unstable because of a genetic defect (as in the various types of inherited epilepsy), or from neurones made unstable by metabolic abnormalities such as low blood glucose, or alcohol. Alternatively, the abnormal discharge may come from a localised area of the brain (this is the situation in patients with epilepsy caused by head injury, or brain tumour). This abnormal discharge is also known as a seizure.
What Is An Aura?
Before the onset of a seizure some people experience a sensation or warning called an "aura". The type of aura experienced varies from person to person, common auras are:
- a change in body temperature.
- a feeling of tension or anxiety.
- a sound (an auditory aura).
- a strange taste.
- a particular curious odour.
A physician with a good description of this aura, may be able to determine which part of the brain where the initial discharges originate. An aura could occur without being followed by a seizure, and in some cases can by itself be called a type of simple partial seizure.
Who Can Have Epilepsy?
Virtually everyone can have a seizure under the right circumstances. Each of us has a brain seizure threshold which makes us more or less resistant to seizures. Seizures can have many causes, including brain injury, poisoning, head trauma, or stroke; and these factors are not restricted to any age group, sex, or race and neither is Epilepsy.
What Age Group Is Affected?
Epilepsy can strike anyone at any age. However, some age groups are more susceptible than others:
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Most people who develop seizures during their earlier years tend to experience a reduction in the intensity and frequency of their seizures as they grow older. In many cases the epilepsy will disappear completely.
How Long Does A Seizures Last?
Depending on the type of seizure, they can last anywhere from a few seconds to several minutes. In rare cases, seizures can last many hours. For example, a to