The Future of Neuroscience
Epilepsy
Epilepsy is a mental disorder distinguished by seizures caused by abnormal activity of neurons in the brain. Of the entire American population, 10% will experience a seizure in their lifetime. Epilepsy affects about 3 million Americans, and about 200,000 new cases occur every year. Epilepsy can affect people of all ages, but it affects more people between the ages of 2 and 45. Incidence is higher in males and socially disadvantageous populations. Prevalence in epilepsy tends to increase as the person ages and does not seem to affect Caucasians as much as racial minorities. Of the 300,000 people who have a first seizure every year, 120,000 of them are under the age of 18.
Diagnosis happens with a neurologist who will determine what types of seizures the patient is having and what causes them. Diagnosis includes a careful examination of medical history and a thorough physical examination. Doctors will examine the patient's nervous system and analyze bodily fluids. Electroencephalgraphs, or EEG (pictured) may also be used in diagnosis. These machines pick up brain waves and electrical signals during seizures. Doctors may also use imaging methods such as using CT (computerized tomography) or MRI (magnetic resonance imaging) scans.
Epilepsy is best known for causing seizures, but convulsions can cause other symptoms. Doctors categorize different types of seizures, and each type has its own symptoms. Absence seizures are most common in children from ages 4 to 12. During an absence seizure, patients stop what they are doing and blankly stare for a few moments, after which they continue what they were doing as if nothing happened. Generalized tonic clonic seizures, also known as grand mal seizures, are the most recognizable and can last for up to three minutes. During a generalized tonic clonic seizure, patients experience a stiffening of the limbs, followed by jerking motions. These seizures are caused by abnormal electrical activity in the brain. In partial seizures, only one side of the brain is affected, therefore the person is aware of what is happening. Patients may experience hallucinations or jerking motions, and during complex partial seizures may mumble or wander.
In many cases of epilepsy, the causes are unidentifiable. However, some possible causes of epilepsy are genetic influence (about 500 genes could be linked to the condition), head trauma (traumatic injury to the head), brain conditions (tumors or strokes), infectious diseases (meningitis, AIDS, etc.) , prenatal injury (unborn babies could be influenced by infection in the mother, poor nutrition or lack of oxygen), and developmental disorders. Patients are diagnosed with symptomatic seizures (pictured) when their case of epilepsy is found to be linked to a cause. If no cause can be found, patients are diagnosed with cryptogenic seizures (pictured). When a genetic factor for epilepsy is identified, primary or idiopathic seizures are diagnosed.
Treatment for epilepsy can include surgery or medication. Surgery can stop seizures caused by abnormal blood vessels, bleeding in the brain, and tumors. Medications that are taken to control the occurence of seizures are called anticonvulsants. Medically refractive epilepsy is epilepsy that does not get better after medication. Children with epilepsy are sometimes placed on special diets to help improve their condition. Diets similar to the Atkins diet that are low in carbohydrates may be helpful for adults, while the most popular diet for children is the ketogenic diet (pictured). The ketogenic diet is meant to maintain starvation of a long period of time. When the body is in a fasting state, it creates ketones because fats are the primary source of calories. During fasting periods, it has been observed that epilepsy may lessen or disappear.
MGE Cells Can Lead to the Cure of Seizures
Research at the University of California discovered that the implantation of medial ganglionic eminence (MGE) cells in the hippocampus can reduce the prevalence of seizures within the mice they tested after just one implant. The hippocampus is known for its function in learning and memory and is also the main area of the brain associated with epileptic seizures. These MGE cells come from cells early in embryo development. When they were introduced to mice’s brains, they integrated themselves within the brain and eventually replaced deficient cells. This gives rise to the hope that we can use embryonic stem cells of our own to cure seizures in epileptic patients.
