What is an electroencephalogram (EEG)?
The EEG is an important test used for diagnosing epilepsy. EEGs help doctors determine the course of treatment for an individual patient. EEGs display the electrical activity of the brain. Nerve cells in the brain are constantly creating small electrical signals, whether a patient is awake or asleep. Measuring electrode placements allow technicians to get clear brainwave recordings by knowing precise distances between all electrodes. The electrical signals are picked up by electrodes glued to the scalp and travel to the amplifiers of the EEG. Here the signals are amplified so they create tracings on a computer or paper. The technician constantly has to watch the EEG to make sure electrodes are working properly and to eliminate any artifact or electrical interference that might occur. Many people with seizures do not have a brain lesion detectable by a magnetic resonance imaging (MRI) scan.
