The Brain and Electricity
The brain uses electricity to allow different brain cells (called neurons) to communicate. When a nerve gets stimulated, it opens small channels in its membrane (the wall that surrounds cells of all kinds and helps keep them together) to let small, electrically charged molecules (called ions) enter. This generates a small, localized charge in part of the neuron, which causes nearby channels to open. This causes a small, electrical charge to be generated further down the neuron. As a result, a small, electrical signal travels from one end of the neuron to the other, where it causes chemicals to be released to stimulate the next neuron.
Electricity and Seizures
Seizures are caused by abnormal electrical activity in the brain. Because the electrical system in the brain is very sensitive, it’s easy to upset the balance and cause unusual electrical discharges. Because communication between brain cells involves electricity, a small electrical abnormality can cause effects on multiple cells, causing them to have a flurry of disorganized activity and stimulation. Sometimes the cause of a seizure can be identified, such as when seizures are caused by brain tumors, brain damage, infections or a fever. However, much of the time the underlying cause of a seizure is not known.
Because the brain controls body movements, consciousness, and perception and thinking, any or all of these can be affected during a seizure. As a result, a vast spectrum of things can happen during a seizure. Sometimes patients jerk and have extreme muscle spasms (called a tonic-clonic seizure). Other times, the patient “freezes” for a short period, during which he isn’t actually conscious as to what is going on. Some patients experience a sensation called an aura that signals a seizure is about to occur, although characteristics of this vary from patient to patient and may be difficult to describe.