Epilepsy & Seizures: Hope Through Research, Part II
Most people with epilepsy lead outwardly normal lives. Approximately 80 percent can be significantly helped by modern therapies, and some may go months or years between seizures. However, epilepsy can and does affect daily life for people with epilepsy, their families, and their friends. People with severe seizures that resist treatment have, on average, a shorter life expectancy and an increased risk of cognitive impairment, particularly if the seizures developed in early childhood. These impairments may be related to the underlying conditions that cause epilepsy or to epilepsy treatment rather than the epilepsy itself.
Behavior and Emotions
It is not uncommon for people with epilepsy, especially children, to develop behavioral and emotional problems. Sometimes these problems are caused by embarrassment or frustration associated with epilepsy. Other problems may result from bullying, teasing, or avoidance in school and other social settings. In children, these problems can be minimized if parents encourage a positive outlook and independence, do not reward negative behavior with unusual amounts of attention, and try to stay attuned to their child's needs and feelings. Families must learn to accept and live with the seizures without blaming or resenting the affected person. Counseling services can help families cope with epilepsy in a positive manner. Epilepsy support groups also can help by providing a way for people with epilepsy and their family members to share their experiences, frustrations, and tips for coping with the disorder.
People with epilepsy have an increased risk of poor self-esteem, depression, and suicide. These problems may be a reaction to a lack of understanding or discomfort about epilepsy that may result in cruelty or avoidance by other people. Many people with epilepsy also live with an ever-present fear that they will have another seizure.
Driving and Recreation
For many people with epilepsy, the risk of seizures restricts their independence, in particular the ability to drive. Most states and the District of Columbia will not issue a driver's license to someone with epilepsy unless the person can document that they have gone a specific amount of time without a seizure (the waiting period varies from a few months to several years). Some states make exceptions for this policy when seizures don't impair consciousness, occur only during sleep, or have long auras or other warning signs that allow the person to avoid driving when a seizure is likely to occur. Studies show that the risk of having a seizure-related accident decreases as the length of time since the last seizure increases. One study found that the risk of having a seizure-related motor vehicle accident is 93 percent less in people who wait at least 1 year after their last seizure before driving, compared to people who wait for shorter intervals.
The risk of seizures also restricts people's recreational choices. For instance, people with epilepsy should not participate in sports such as skydiving or motor racing where a moment's inattention could lead to injury. Other activities, such as swimming and sailing, should be done only with precautions and/or supervision. However, jogging, football, and many other sports are reasonably safe for a person with epilepsy. Studies to date have not shown any increase in seizures due to sports, although these studies have not focused on any activity in particular. There is some evidence that regular exercise may even improve seizure control in some people. Sports are often such a positive factor in life that it is best for the person to participate, although the person with epilepsy and the coach or other leader should take appropriate safety precautions. It is important to take steps to avoid potential sports-related problems such as dehydration, overexertion, and hypoglycemia, as these problems can increase the risk of seizures.
Education and Employment
By law, people with epilepsy or other handicaps in the United States cannot be denied employment or access to any educational, recreational, or other activity because of their seizures. However, one survey showed that only about 56 percent of people with epilepsy finish high school and about 15 percent finish college, rates much lower than those for the general population. The same survey found that about 25 percent of working-age people with epilepsy are unemployed. These numbers indicate that significant barriers still exist for people with epilepsy in school and work. Restrictions on driving limit the employment opportunities for many people with epilepsy, and many find it difficult to face the misunderstandings and social pressures they encounter in public situations. Antiepileptic drugs also may cause side effects that interfere with concentration and memory. Children with epilepsy may need extra time to complete schoolwork, and they sometimes may need to have instructions or other information repeated for them. Teachers should be told what to do if a child in their classroom has a seizure, and parents should work with the school system to find reasonable ways to accommodate any special needs their child may have.
Pregnancy and Motherhood
Women with epilepsy are often concerned about whether they can become pregnant and have a healthy child. This is usually possible. While some seizure medications and some types of epilepsy may reduce a person's interest in sexual activity, most people with epilepsy can become pregnant. Moreover, women with epilepsy have a 90 percent or better chance of having a normal, healthy baby, and the risk of birth defects is only about 4-6 percent. The risk that children of parents with epilepsy will develop epilepsy themselves is only about 5 percent unless the parent has a clearly hereditary form of the disorder. Parents who are worried that their epilepsy may be hereditary may wish to consult a genetic counselor to determine what the risk might be. Amniocentesis and high-level ultrasound can be performed during pregnancy to ensure that the baby is developing normally, and a procedure called a maternal serum alpha-fetoprotein test can be used for prenatal diagnosis of many conditions if a problem is suspected.
There are several precautions women can take before and during pregnancy to reduce the risks associated with pregnancy and delivery. Women who are thinking about becoming pregnant should talk with their doctors to learn any special risks associated with their epilepsy and the medications they may be taking. Some seizure medications, particularly valproate, trimethadione, and phenytoin, are known to increase the risk of having a child with birth defects such as cleft palate, heart problems, or finger and toe defects. For this reason, a woman's doctor may advise switching to other medications during pregnancy. Whenever possible, a woman should allow her doctor enough time to properly change medications, including phasing in the new medications and checking to determine when blood levels are stabilized, before she tries to become pregnant. Women should also begin prenatal vitamin supplements, especially with folic acid, which may reduce the risk of some birth defects, well before pregnancy. Women who discover that they are pregnant but have not already spoken with their doctor about ways to reduce the risks should do so as soon as possible. However, they should continue taking seizure medication as prescribed until that time to avoid preventable seizures. Seizures during pregnancy can harm the developing baby or lead to miscarriage, particularly if the seizures are severe. Nevertheless, many women who have seizures during pregnancy have normal, healthy babies.
Women with epilepsy sometimes experience a change in their seizure frequency during pregnancy, even if they do not change medications. About 25 to 40 percent of women have an increase in their seizure frequency while they are pregnant, while other women may have fewer seizures during pregnancy. The frequency of seizures during pregnancy may be influenced by a variety of factors, including the woman's increased blood volume during pregnancy, which can dilute the effect of medication. Women should have their blood levels of seizure medications monitored closely during and after pregnancy, and the medication dosage should be adjusted accordingly.
Pregnant women with epilepsy should take prenatal vitamins and get plenty of sleep to avoid seizures caused by sleep deprivation. They also should take vitamin K supplements after 34 weeks of pregnancy to reduce the risk of a blood-clotting disorder in infants called neonatal coagulopathy that can result from fetal exposure to epilepsy medications. Finally, they should get good prenatal care, avoid tobacco, caffeine, alcohol, and illegal drugs, and try to avoid stress.
Labor and delivery usually proceed normally for women with epilepsy, although there is a slightly increased risk of hemorrhage, eclampsia, premature labor, and cesarean section. Doctors can administer antiepileptic drugs intravenously and monitor blood levels of anticonvulsant medication during labor to reduce the risk that the labor will trigger a seizure. Babies sometimes have symptoms of withdrawal from the mother's seizure medication after they are born, but these problems wear off in a few weeks or months and usually do not cause serious or long-term effects. A mother's blood levels of anticonvulsant medication should be checked frequently after delivery as medication often needs to be decreased.
Epilepsy medications need not influence a woman's decision about breast-feeding her baby. Only minor amounts of epilepsy medications are secreted in breast milk; usually not enough to harm the baby and much less than the baby was exposed to in the womb. On rare occasions, the baby may become excessively drowsy or feed poorly, and these problems should be closely monitored. However, experts believe the benefits of breast-feeding outweigh the risks except in rare circumstances.
Women with epilepsy should be aware that some epilepsy medications can interfere with the effectiveness of oral contraceptives. Women who wish to use oral contraceptives to prevent pregnancy should discuss this with their doctors, who may be able to prescribe a different kind of antiepileptic medication or suggest other ways of avoiding an unplanned pregnancy.
Are There Special Risks Associated With Epilepsy?
Although most people with epilepsy lead full, active lives, they are at special risk for two life-threatening conditions: status epilepticus and sudden unexplained death.
Status epilepticus is a severe, life-threatening condition in which a person either has prolonged seizures or does not fully regain consciousness between seizures. The amount of time in a prolonged seizure that must pass before a person should be diagnosed with status epilepticus is a subject of debate. Many doctors now diagnose status epilepticus if a person has been in a prolonged seizure for 5 minutes. However, other doctors use more conservative definitions of this condition and may not diagnose status epilepticus unless the person has had a prolonged seizure of 10 minutes or even 30 minutes.
Status epilepticus affects about 195,000 people each year in the United States and results in about 42,000 deaths. While people with epilepsy are at an increased risk for status epilepticus, about 60 percent of people who develop this condition have no previous seizure history. These cases often result from tumors, trauma, or other problems that affect the brain and may themselves be life-threatening.
While most seizures do not require emergency medical treatment, someone with a prolonged seizure lasting more than 5 minutes may be in status epilepticus and should be taken to an emergency room immediately. It is important to treat a person with status epilepticus as soon as possible. One study showed that 80 percent of people in status epilepticus who received medication within 30 minutes of seizure onset eventually stopped having seizures, whereas only 40 percent recovered if 2 hours had passed before they received medication. Doctors in a hospital setting can treat status epilepticus with several different drugs and can undertake emergency life-saving measures, such as administering oxygen, if necessary.
People in status epilepticus do not always have severe convulsive seizures. Instead, they may have repeated or prolonged nonconvulsive seizures. This type of status epilepticus may appear as a sustained episode of confusion or agitation in someone who does not ordinarily have that kind of mental impairment. While this type of episode may not seem as severe as convulsive status epilepticus, it should still be treated as an emergency.
Sudden Unexplained Death
For reasons that are poorly understood, people with epilepsy have an increased risk of dying suddenly for no discernible reason. This condition, called sudden unexplained death, can occur in people without epilepsy, but epilepsy increases the risk about two-fold. Researchers are still unsure why sudden unexplained death occurs. One study suggested that use of more than two anticonvulsant drugs may be a risk factor. However, it is not clear whether the use of multiple drugs causes the sudden death, or whether people who use multiple anticonvulsants have a greater risk of death because they have more severe types of epilepsy.
What Research Is Being Done on Epilepsy?
While research has led to many advances in understanding and treating epilepsy, there are many unanswered questions about how and why seizures develop, how they can best be treated or prevented, and how they influence other brain activity and brain development. Researchers, many of whom are supported by the National Institute of Neurological Disorders and Stroke (NINDS), are studying all of these questions. They also are working to identify and test new drugs and other treatments for epilepsy and to learn how those treatments affect brain activity and development. NINDS' Epilepsy Therapeutics Research Program studies potential antiepileptic drugs with the goal of enhancing treatment for epilepsy. Since it began in 1975, this program has screened more than 22,000 compounds for their potential as antiepileptic drugs and has contributed to the development of five drugs that are now approved for use in the United States as well as others that are still being developed or tested.
Scientists continue to study how excitatory and inhibitory neurotransmitters interact with brain cells to control nerve firing. They can apply different chemicals to cultures of neurons in laboratory dishes to study how those chemicals influence neuronal activity. They also are studying how glia and other non-neuronal cells in the brain contribute to seizures. This research may lead to new drugs and other new ways of treating seizures.
Researchers also are working to identify genes that may influence epilepsy in some way. Identifying these genes can reveal the underlying chemical processes that influence epilepsy and point to new ways of preventing or treating this disorder. Researchers also can study rats and mice that have missing or abnormal copies of certain genes to determine how these genes affect normal brain development and resistance to damage from disease and other environmental factors. Researchers may soon be able to use devices called gene chips to determine each person's genetic makeup or to learn which genes are active. This information may allow doctors to prevent epilepsy or to predict which treatments will be most beneficial.
Doctors are now experimenting with several new types of therapies for epilepsy. In one preliminary clinical trial, doctors have begun transplanting fetal pig neurons that produce GABA into the brains of patients to learn whether the cell transplants can help control seizures. Preliminary research suggests that stem cell transplants also may prove beneficial for treating epilepsy. Research showing that the brain undergoes subtle changes prior to a seizure has led to a prototype device that may be able to predict seizures up to 3 minutes before they begin. If this device works, it could greatly reduce the risk of injury from seizures by allowing people to move to a safe area before their seizures start. This type of device also may be hooked up to a treatment pump or other device that will automatically deliver an antiepileptic drug or an electric impulse to forestall the seizures.
Researchers are continually improving MRI and other brain scans. Pre-surgical brain imaging can guide doctors to abnormal brain tissue and away from essential parts of the brain. Researchers also are using brain scans such as magnetoencephalograms (MEG) and magnetic resonance spectroscopy (MRS) to identify and study subtle problems in the brain that cannot otherwise be detected. Their findings may lead to a better understanding of epilepsy and how it can be treated.
How Can I Help Research on Epilepsy?
There are many ways that people with epilepsy and their families can help with research on this disorder. Pregnant women with epilepsy who are taking antiepileptic drugs can help researchers learn how these drugs affect unborn children by participating in the Antiepileptic Drug Pregnancy Registry, which is maintained by the Genetics and Teratology Unit of Massachusetts General Hospital (see section on Pregnancy and Motherhood). People with epilepsy that may be hereditary can aid research by participating in the Epilepsy Gene Discovery Project, which is supported by the Epilepsy Foundation. This project helps to educate people with epilepsy about new genetic research on the disorder and enlists families with hereditary epilepsy for participation in gene research. People who enroll in this project are asked to create a family tree showing which people in their family have or have had epilepsy. Researchers then examine this information to determine if the epilepsy is in fact hereditary, and they may invite participants to enroll in genetic research studies. In many cases, identifying the gene defect responsible for epilepsy in an individual family leads researchers to new clues about how epilepsy develops. It also can provide opportunities for early diagnosis and genetic screening of individuals in the family.
People with epilepsy can help researchers test new medications, surgical techniques, and other treatments by enrolling in clinical trials. Information on clinical trials can be obtained from the NINDS as well as many private pharmaceutical and biotech companies, universities, and other organizations. A person who wishes to participate in a clinical trial must ask his or her regular physician to refer him or her to the doctor in charge of that trial and to forward all necessary medical records. While experimental therapies may benefit those who participate in clinical trials, patients and their families should remember that all clinical trials also involve some risks. Therapies being tested in clinical trials may not work, and in some cases doctors may not yet be certain that the therapies are safe. Patients should be certain they understand the risks before agreeing to participate in a clinical trial.
NINDS supports a number of Epilepsy Research Centers that perform a broad spectrum of clinical research on epilepsy. Some of the studies require patient volunteers. A list of these centers is available from the NIH Neurological Institute, which can be reached at the address and phone number found on the Information Resources card in the back pocket of this brochure.
Patients and their families also can help epilepsy research by donating their brain to a brain bank after death. Brain banks supply researchers with tissue they can use to study epilepsy and other disorders.
What To Do If You See Someone Having a Seizure
If you see someone having a seizure with convulsions and/or loss of consciousness, here's how you can help:
- Roll the person on his or her side to prevent choking on any fluids or vomit.
- Cushion the person's head.
- Loosen any tight clothing around the neck.
- Keep the person's airway open. If necessary, grip the person's jaw gently and tilt his or her head back.
- Do NOT restrict the person from moving unless he or she is in danger.
- Do NOT put anything into the person's mouth, not even medicine or liquid. These can cause choking or damage to the person's jaw, tongue, or teeth. Contrary to widespread belief, people cannot swallow their tongues during a seizure or any other time.
- Remove any sharp or solid objects that the person might hit during the seizure.
- Note how long the seizure lasts and what symptoms occurred so you can tell a doctor or emergency personnel if necessary.
- Stay with the person until the seizure ends.
Call 911 if:
- The person is pregnant or has diabetes.
- The seizure happened in water.
- The seizure lasts longer than 5 minutes.
- The person does not begin breathing again and return to consciousness after the seizure stops.
- Another seizure starts before the person regains consciousness.
- The person injures himself or herself during the seizure.
- This is a first seizure or you think it might be. If in doubt, check to see if the person has a medical identification card or jewelry stating that they have epilepsy or a seizure disorder.
After the seizure ends, the person will probably be groggy and tired. He or she also may have a headache and be confused or embarrassed. Be patient with the person and try to help him or her find a place to rest if he or she is tired or doesn't feel well. If necessary, offer to call a taxi, a friend, or a relative to help the person get home safely.
If you see someone having a non-convulsive seizure, remember that the person's behavior is not intentional. The person may wander aimlessly or make alarming or unusual gestures. You can help by following these guidelines:
- Remove any dangerous objects from the area around the person or in his or her path.
- Don't try to stop the person from wandering unless he or she is in danger.
- Don't shake the person or shout.
- Stay with the person until he or she is completely alert.
Many people with epilepsy lead productive and outwardly normal lives. Many medical and research advances in the past two decades have led to a better understanding of epilepsy and seizures than ever before. Advanced brain scans and other techniques allow greater accuracy in diagnosing epilepsy and determining when a patient may be helped by surgery. More than 20 different medications and a variety of surgical techniques are now available and provide good control of seizures for most people with epilepsy. Other treatment options include the ketogenic diet and the first implantable device, the vagus nerve stimulator. Research on the underlying causes of epilepsy, including identification of genes for some forms of epilepsy and febrile seizures, has led to a greatly improved understanding of epilepsy that may lead to more effective treatments or even new ways of preventing epilepsy in the future.
Note: Due to the large number of epilepsy syndromes and treatments, only a few are discussed in this booklet. Additional information may be available from your doctor or other health professionals, from medical libraries, or by calling the NINDS Office of Communications and Public Liaison at the number provided on the Information Resources card in the back pocket of this brochure.
- absence epilepsy epilepsy in which the person has repeated absence seizures.
- absence seizures the type of seizure seen in absence epilepsy, in which the person experiences a momentary loss in consciousness. The person may stare into space for several seconds and may have some twitching or jerking of muscles.
- ACTH (adrenocorticotropic hormone) a substance that can be used to treat infantile spasms.
- atonic seizures seizures which cause a sudden loss of muscle tone, also called drop attacks.
- auras unusual sensations or movements that warn of an impending, more severe seizure. These auras are actually simple partial seizures in which the person maintains consciousness.
- automatisms strange, repetitious behaviors that occur during a seizure. Automatisms may include blinks, twitches, mouth movements, or even walking in a circle.
- benign epilepsy syndrome epilepsy syndromes that do not seem to impair cognitive function or development.
- benign infantile encephalopathy a type of epilepsy syndrome that occurs in infants. It is considered benign because it does not seem to impair cognitive functions or development.
- benign neonatal convulsions a type of epilepsy syndrome in newborns that does not seem to impair cognitive functions or development.
- biofeedback a strategy in which individuals learn to control their own brain waves or other normally involuntary functions. This is an experimental treatment for epilepsy.
- celiac disease an intolerance to wheat gluten in foods that can lead to seizures and other symptoms.
- clonic seizures seizures that cause repeated jerking movements of muscles on both sides of the body.
- complex partial seizures seizures in which only one part of the brain is affected, but the person has a change in or loss of consciousness.
- convulsions seizures accompanied by involuntary jerking movements.
- corpus callosotomy surgery that severs the corpus callosum, the network of neural connections between the right and left hemispheres of the brain.
- CT (computed tomography) a type of brain scan that reveals the structure of the brain.
- drop attacks seizures that cause sudden falls; another term for atonic seizures.
- dysplasia areas of misplaced or abnormally formed neurons in the brain.
- early myoclonic encephalopathy a type of epilepsy syndrome that usually includes neurological and developmental problems.
- eclampsia a life-threatening condition that can develop in pregnant women. Its symptoms include sudden elevations of blood pressure and seizures.
- electroencephalogram (EEG) a test which uses electrodes to record brain waves.
- epilepsy syndromes disorders with a specific set of symptoms that include epilepsy.
- excitatory neurotransmitters nerve signaling chemicals that increase activity in neurons.
- febrile seizures seizures in infants and children that are associated with a high fever.
- frontal lobe epilepsy a type of epilepsy that originates in the frontal lobe of the brain. It usually involves a cluster of short seizures with a sudden onset and termination.
- functional MRI ((functional magnetic resonance imaging) a type of brain scan that can be used to monitor the brain's activity and to detect abnormalities in how it works.
- GABA (gamma-aminobutyric acid) an inhibitory neurotransmitter that plays a role in some types of epilepsy.
- generalized seizures seizures that result from abnormal neuronal activity in many parts of the brain. These seizures may cause loss of consciousness, falls, or massive muscle spasms.
- glia cells that regulate concentrations of chemicals that affect neuron signaling and perform other important functions in the brain.
- glutamate an excitatory neurotransmitter that may play a role in some types of epilepsy.
- grand mal seizures an older term for tonic-clonic seizures.
- hemispheres the right and left halves of the brain.
- hippocampus a brain structure important for memory and learning.
- idiopathic epilepsy epilepsy with an unknown cause.
- infantile spasms clusters of seizures that usually begin before the age of 6 months. During these seizures the infant may bend and cry out.
- inhibitory neurotransmitters nerve signaling chemicals that decrease activity in neurons.
- intractable epilepsy epilepsy in which a person continues to experience seizures even with the best available treatment.
- ion channels molecular "gates" that control the flow of ions in and out of cells and regulate neuron signaling.
- juvenile myoclonic epilepsy a type of epilepsy that usually begins in childhood or adolescence and is characterized by sudden myoclonic jerks.
- ketogenic diet a strict diet rich in fats and low in carbohydrates that causes the body to break down fats instead of carbohydrates to survive.
- kindling a phenomenon in which a small change in neuronal activity, if it is repeated, may eventually lead to full-blown epilepsy.
- LaFora's disease a severe, progressive form of epilepsy that begins in childhood and has been linked to a gene that helps to break down carbohydrates.
- Lennox-Gastaut syndrome a type of epilepsy that begins in childhood and usually causes several different kinds of seizures.
- lesion a damaged or dysfunctional part of the brain or other parts of the body.
- lesionectomy removal of a specific brain lesion.
- lobectomy removal of a lobe of the brain.
- magnetic resonance spectroscopy (MRS) a type of brain scan that can detect abnormalities in the brain's biochemical processes.
- magnetoencephalogram (MEG) a diagnostic recording technique that detects the magnetic signals generated by neurons to allow doctors to monitor brain activity at different points in the brain over time, revealing different brain functions.
- metabolized broken down or otherwise transformed by the body.
- monotherapy treatment with only one antiepileptic drug.
- MRI (magnetic resonance imaging) a type of brain scan that reveals the structure of the brain; see also functional MRI.
- multiple sub-pial transection a type of operation in which surgeons make a series of cuts in the brain that are designed to prevent seizures from spreading into other parts of the brain while leaving the personï¿½s normal abilities intact.
- mutation an abnormality in a gene.
- myoclonic seizures that cause sudden jerks or twitches, especially in the upper body, arms, or legs.
- near-infrared spectroscopy a technique that can detect oxygen levels in brain tissue.
- neurocysticercosis a parasitic infection of the brain that can cause seizures.
- neurotransmitters nerve signaling chemicals.
- nonconvulsivea ny type of seizure that does not include violent muscle contractions.
- nonepileptic events any phenomena that look like seizures but which do no include seizure activity in the brain. Nonepileptic events may include psychogenic seizures or symptoms of medical disorders such as sleep disorders, Tourette syndrome, or cardiac arrhythmia.
- occipital lobe epilepsy epilepsy with seizures that originate in the occipital lobe of the brain. It usually begins with visual hallucinations, rapid eye blinking or other eye-related symptoms.
- parietal lobe epilepsy epilepsy that originates in the parietal lobe of the brain. The symptoms of parietal lobe epilepsy closely resemble those of temporal lobe epilepsy or other syndromes.
- partial seizures seizures that occur in just one part of the brain.
- PET (positron emission tomography), a type of brain scan that can be used to monitor the brain's activity and detect abnormalities in how it works.
- petit mal seizures an older term for absence seizures.
- photosensitive epilepsy epilepsy with seizures triggered by flickering or flashing lights. It also may be called photic epilepsy or photogenic epilepsy.
- prednisone a drug that can be used to treat infantile spasms.
- progressive epilepsy syndromes epilepsy syndromes in which seizures and/or the person's cognitive or motor abilities get worse.
- progressive myoclonus epilepsy a type of epilepsy that has been linked to an abnormality in the gene that codes for a protein called cystatin B. This protein regulates enzymes that break down other proteins.
- pseudoseizure another term for a non-epileptic event.
- psychogenic seizure a type of non-epileptic event that is caused by psychological factors.
- psychomotor epilepsy another term for partial seizures, especially seizures of the temporal lobe. The term psychomotor refers to the unusual sensations, emotions, and behavior seen with these seizures.
- Ramsay Hunt syndrome type II a type of rare and severe progressive epilepsy that usually begins in early adulthood.
- Rasmussen's encephalitis a progressive type of epilepsy in which the focus of epileptic activity expands over time. This type of epilepsy is sometimes treated with hemispherectomy.
- seizure focus an area of the brain where seizures originate.
- seizure threshold a term that refers to a personï¿½s susceptibility to seizures.
- seizure triggers phenomena that trigger seizures in some people. Seizure triggers do not cause epilepsy but can lead to first seizures or cause breakthrough seizures in people who otherwise experience good seizure control with their medication.
- simple partial seizures seizures that affect only one part of the brain. People experiencing simple partial seizures remain conscious but may experience unusual feelings or sensations.
- SPECT (single photon emission computed tomography) a type of brain scan sometimes used to locate seizure foci in the brain.
- status epilepticus a potentially life-threatening condition in which seizures are prolonged or recur before the person can regain consciousness.
- stereotyped similar every time. In epilepsy this refers to the symptoms an individual person has, and the progression of those symptoms.
- sudden unexplained death death that occurs suddenly for no discernible reason. Epilepsy increases the risk of sudden explained death about two-fold.
- temporal lobe epilepsy the most common epilepsy syndrome with partial seizures.
- temporal lobe resection a type of surgery for temporal lobe epilepsy in which all or part of the affected temporal lobe of the brain is removed.
- tonic seizures seizures that cause stiffening of muscles of the body, generally those in the back, legs, and arms.
- tonic-clonic seizures seizures that cause a mixture of symptoms, including loss of consciousness, stiffening of the body, and repeated jerks of the arms and legs. In the past these seizures were sometimes referred to as grand mal seizures.
- transcranial magnetic stimulation (TMS) a procedure which uses a strong magnet held outside the head to influence brain activity. This is an experimental treatment for seizures.
Source: National Institute of Neurological Disorders and Stroke, National Institutes of Health