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Electroencephalogram (EEG)

An electroencephalogram procedure with woman wearing cap

An EEG may be done to study seizures, study sleep disorders, or help find the location of a tumor, an infection, or bleeding. An EEG technologist attaches a cap with fixed electrodes on your head. (An EEG can also be done without a cap by using several individual electrodes.) The electrodes are hooked by wires to a machine that records the electrical activity inside the brain. The machine shows the electrical activity as a series of wavy lines on a computer screen.

Current as of: June 17, 2021

Author: Healthwise Staff
Medical Review:
Anne C. Poinier MD - Internal Medicine
Adam Husney MD - Family Medicine
Martin J. Gabica MD - Family Medicine
Karin M. Lindholm DO - Neurology