Neurons and Electricity
Neurons are the cells within the brain that are responsible for generating and passing along the signals that control cognition as well as the body's functions. Neurons are interconnected through junctures called synapses, which allow neurons to communicate using chemical signals. Nerve signals within a neuron, however, are caused by electrical currents that go from one end of the neuron to the other (called an action potential), which causes the nerve to "fire". The firing of a nerve causes it to release chemicals into its associated synapses, which causes stimulation and firing of other nerves. Sometimes neurons develop abnormal electrical activity that causes them to fire extremely rapidly, at a rate of around 500 signals per second. This in turn causes hyperactivity of other neurons and leads to a sudden burst of activity of many neurons at once, which can cause neuronal dysfunction and a seizure.
Epilepsy Causes
Epileptic seizures describe abnormal neuron activity that has an electrical origin. Sometimes seizures have a distinct cause, such as elevated pressure caused by a brain tumor or damaged nerve tissue. Other factors that can lead to epilepsy are a high fever, certain infections (such as malaria, AIDS and meningitis), as well as abnormally high or low levels of sugar and/or sodium in the blood. Epilepsy can also be caused by alcohol abuse, amphetamines or cocaine use. However, according to the Epilepsy Foundation, approximately 70 percent of all cases of epilepsy have no identifiable cause. Regardless of the cause, epileptic seizures can be traced to abnormal brain electrical activity, which causes the symptoms of the seizure (though the exact seizure symptoms vary from one patient to the next).
Non-Epileptic Seizures
According to the Epilepsy Foundation, non-epileptic seizures describe seizures that are not caused by abnormal brain electrical activity. They can be caused by physiologic problems that cause the neurons to behave abnormally (such as brain damage from a stroke). They can also have a psychological cause, such as extreme emotional stress or powerful psychological trauma. What exactly triggers non-epileptic seizures is still unknown and often the only way of differentiating them from epileptic seizures is to measure the brain's electrical activity (using a device called an electroencephalogram) during the seizure.
