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Definition
By Mayo Clinic staff
An electroencephalogram (EEG) is a painless procedure that uses small, flat metal discs (electrodes) attached to your scalp to detect electrical activity in your brain. Your brain cells communicate via electrical impulses and are active all the time, even when you're asleep. This activity shows up as wavy lines on an EEG recording.
An EEG is one of the main diagnostic tests for epilepsy. An EEG may also play a role in diagnosing other brain disorders.
Why it's done
References
- Aminoff MJ. Electrophysiology. In: Goetz CG. Textbook of Clinical Neurology. 3rd ed. Philadelphia, Pa.: Elsevier Saunders; 2007. http://www.mdconsult.com/das/book/body/125576141-3/0/1488/222.html?tocnode=53801707&fromURL=222.html#4-u1.0-B978-1-4160-3618-0..10024-4_1475. Accessed March 12, 2009.
- Hirsch LJ, et al. Electroencephalography (EEG) in the diagnosis of seizures and epilepsy. http://www.uptodate.com/home/index.html. Accessed March 12, 2009.
- Aminoff MJ. Electrodiagnostic studies of nervous system disorders: EEG, evoked potentials and EMG. In: Fauci AS, et al. Harrison's Principles of Internal Medicine. 17th ed. New York, N.Y.: The McGraw-Hill Companies; 2008. http://www.accessmedicine.com/content.aspx?aID=2885536. Accessed March 12, 2009.
- Importance of EEG tests. Epilepsy Foundation. http://www.epilepsyfoundation.org/about/quickstart/newlydiagnosed/qstreatment/qstreeg.cfm. Accessed March 18, 2009.
- Neurological diagnostic tests and procedures. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/misc/diagnostic_tests.htm. Accessed March 18, 2009.
- Devinsky O. Epilepsy: Patient and Family Guide. 3rd ed. New York, N.Y.: Demos Medical Publishing LLC; 2008:76.
- Anesthesia and you: Sedation analgesia. American Society of Anesthesiologists. http://www.asahq.org/patientEducation/SedationBrochure.pdf. Accessed March 13, 2009.
