EEG and epilepsy
People with epilepsy have seizures caused by unusual electrical activity in part or all of the brain. Doctors can use an EEG to measure this activity, and diagnose epilepsy (as seizures can have other causes). Unusual bursts of electric activity can sometimes be detected between seizures, and are called 'spikes'. The location of these spikes in the brain can help doctors decide what type of epilepsy the person has, and so what treatment to use.