Electroencephalogram (EEG) – the most important examination for diagnosing epilepsy. Electrodes are fixed on head skin with the help of jellylike matter, which record brain’s bioelectric activities.

If patient has epilepsy, there is a big probability that the normal brain waves pattern will be damaged even when there is no seizure at the moment of test. In ambiguous cases it is reasonable to perform EEG recording together with video monitoring for long periods during sleep and being awake, in order to register a seizure. An EEG recording of a seizure simplifies diagnostication. Sometimes, with the aim of provoking seizure, sleep deprivation (decrease of sleep duration) is conducted before EEG examination upon doctor’s instructions.