Standard and extended electroencephalography (EEG).

Standard EEG is a test that records the electrical activity of the brain via electrodes placed on the scalp. It usually lasts 20 to 40 minutes, during which the patient remains calm, with eyes closed or open, with activation phases such as hyperventilation or intermittent light stimulation.

Prolonged EEG aims to detect rare or nocturnal abnormalities by recording brain activity over a period of several hours or even days. This method, often coupled with video (video-EEG), makes it possible to correlate clinical manifestations with electrical tracings and is carried out in the laboratory.

• Nocturnal seizures vs parasomnias.
• Unexplained arousals or episodic behaviours.
• Pre-surgical evaluation when EEG is required.
• Extended monitoring for subtle or infrequent events.

Standard EEG is outpatient. Prolonged studies may require a hospital or laboratory stay; our team explains duration, hair preparation, and scheduling in advance.