How Seizures Occur

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The brain is an electrochemical machine. Nerve cells or neurons use chemical reactions to generate electricity, like a very complex battery. When a neuron becomes excited, it passes an electrical signal along its thin biological wire, called an axon, to communicate with other neurons in the brain. Those other neurons either can be excited or inhibited by the signal. When too many neurons become excited all at once, a seizure can result. A 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 experience sudden alterations in movements, sensations, awareness or behavior. A seizure typically goes on for a few seconds to a few minutes. The end of a seizure is a transition back to the individual's normal state.

Doctors are often asked what the difference is between a seizure and epilepsy. To the medical community, epilepsy is the condition of having spontaneously recurrent seizures. That means that one isolated seizure is not defined as epilepsy. There must be two or more seizures, or one seizure with a high chance of having another. To count as epilepsy, the seizures have to appear spontaneously, without an immediate precipitating factor. If Johnny falls off his motorcycle, hits his head and has two seizures on the scene, it is not epilepsy, because the seizures were immediately precipitated by head trauma. However, if he recovers, then starts having seizures weeks, months or years later as a result of the traumatic brain injury, then that does count as epilepsy.

Partial seizures sometimes have an aura, which is a warning that bigger seizures may follow. An aura usually occurs seconds to minutes before seizure, but some patients can have periods of warning lasting a day or longer. Technically, the aura is itself a small simple partial seizure. There are many different ways in which people experience an aura. The start of a seizure in one of the temporal lobes can produce unusual feelings, like abnormal sensation or forced thinking. The onset of a complex partial seizure may be heralded by dj vu, a familiar feeling, or jamai vu, an unfamiliar feeling. Some patients have auras of sounds, tastes, distorted vision, racing thoughts, or smells, like burning rubber. Physical sensations occurring as auras are dizziness, headache, lightheadedness, and numbness. An upset stomach is a particularly common phsycial symptom. Auras can include a sense of tingling rising up the body or other strange feelings difficult to describe. Distorted emotions, like fear or panic, can also be a seizure warning.

A tonic-clonic seizure is what most people think of when they hear the word "seizure." Although these seizures are distressing to watch, the person having them is unaware. We don't believe that these seizures are painful, but people can injure themselves by biting their tongue or straining their muscles. The tonic or stiffening phase comes first: All the muscles stiffen. Air being forced past the vocal cords causes a cry or groan. The person loses consciousness and falls down. The tongue or cheek may be bitten, so bloody saliva may come from the mouth. The person may turn blue in the face. After the tonic phase comes the clonic or jerking phase: The arms and usually the legs jerk rapidly and rhythmically, bending and relaxing. After a few minutes, the jerking slows and stops. Bladder or bowel control sometimes is lost as the body relaxes. Consciousness returns slowly, and the person may be drowsy, confused, agitated, or depressed.

Anything that injures the brain can lead to seizures, but in over half the cases no cause can be identified. The type of injury that can lead to a seizure is age-dependent. Seizures in children often are caused by birth traumas, infections like meningitis, congenital abnormalities, or high fevers. Seizures in the middle years commonly are caused by head injuries, infections, alcohol, stimulant drugs, or medication side effects. In the elderly, brain tumors and strokes cause a higher proportion of seizures.

Common chemical imbalances that can produce seizures include: Drugs like alcohol, cocaine, and others. Low blood sugar, low oxygen, low blood sodium, or low blood calcium. Kidney failure, liver failure, or other conditions. Doctors will evaluate you for these imbalances by taking a careful history and blood tests. Although these disorders and injuries can explain many cases of epilepsy, often the cause of epilepsy remains "idiopathic," which is the medical term for unknown.

While brain function can be temporarily disturbed by seizures, brain damage, or a permanent problem with the brain's structure, is not synonymous with epilepsy. Like any other group, people with epilepsy have different intellectual abilities. Some are brilliant, while others have problems with basic cognitive functioning. For the most part though, people with epilepsy have normal intelligence. Although seizures can be confusing and are often misconstrued as violent or challenging behavior, people with epilepsy have no greater tendency toward violence or aggression than do others. Despite ancient falsehood that put epilepsy in the same class as mental illness. In fact, the majority of people with seizures do not develop mental health problems. Single seizures that last less than ten minutes are not known to cause brain damage or injury in the long-term.

Several factors are important in considering someone for possible epilepsy surgery. They include whether the patient has: seizures that are not controlled by systematic medication trials; localized seizure onset in the brain; a level of health that makes brain surgery relatively safe; and an understanding and acceptance of the risks. Generally, epilepsy surgery is considered for people who have seizures that cannot be controlled by anti-epilepsy drugs, because of ongoing seizures, unacceptable side effects, or both. This unfortunate situation - poorly controlled seizures - occurs in 1 out of every 3 people with epilepsy. For epilepsy surgery to be considered, seizures also need to be severe, or frequent enough, to impair quality of life, a standard that varies tremendously for different people. For some people, seizures that prevent them from being able to drive, or high doses of medications that cause continual side-effects, is reason enough to pursue possible surgery.

Access to the deep temporal lobe can be achieved in two ways. The conventional approach involves removing an inch and a half from the tip of the temporal lobe to provide access. The second involves cutting into the outer brain and opening a window from the side. However it is accessed, the hippocampus, amygdala and surrounding brain are removed by a combination of cutting and suction, since brain tissue is soft. All bleeding is carefully controlled during surgery. The surgery does not remove a tiny piece of brain, but rather a sizable part of one lobe. After the removal of the temporal lobe tissue is complete, the bone is replaced and secured to the skull, and the scalp is sutured. Whenever possible, the surgeon uses incisions behind the hair line for the best possible cosmetic results. Patients then move to a recovery room or intensive care unit. A few days post-surgery, though, most move to a normal room and are eating and walking.

A lesion is an abnormal structure in the brain, like an old scar. The scar may be present due to past trauma, bleeding, infection, stroke, abnormal blood vessels, a birth defect, or a tumor. A. Seizures often originate around a lesion,B. so a lesionectomy removes it, C. as well as a rim of surrounding brain tissue believed to be involved in seizures.

A febrile seizure, or even several febrile seizures, does not usually point to epilepsy. This is because these seizures are not spontaneous, and most children outgrow them by age 6. A febrile seizure is a very frightening experience for parents, partly because the fever may not be recognized until after the seizure occurs. In addition, the seizure often takes the form of a convulsion. Still, febrile seizures are usually harmless, unless the child is injured during the seizure.

Once you have a job, you will have to decide whether to let your coworkers, supervisor, or human resources department know about your seizures. So what if you do have seizures on the job and they cause a problem? Once again, the ADA comes to your aid, stating that the company must attempt to make reasonable accommodations for you. For example, there might be another position in the company that would be less problematic, or you might be excused from overtime if missing sleep provokes seizures. If you have been unfairly treated on the job because of epilepsy, you have at least three levels of recourse. First, you can attempt to work the problem out within the company. Second, you can contact your regional Equal Employment Opportunity Commission, which you can find by visiting their website at www.eeoc.gov. The EEOC will hear your story and decide whether to pursue it on your behalf, at no charge. If they take your case, they may communicate with your employer or pursue legal action. The third option is to hire an employment discrimination attorney. While this may be successful, it can also be expensive.