Mayo Clinic Health Manager
Get free personalized health guidance for you and your family.
Get StartedWhy it's done
By Mayo Clinic staffAn EEG can determine changes in brain activity that may be useful in diagnosing brain disorders, especially epilepsy. An EEG may be helpful to confirm, rule out or provide information that helps with management of the following disorders:
- Epilepsy or other seizure disorder
- Brain tumor
- Head injury
- Encephalopathy — diffuse brain dysfunction
- Inflammation of the brain (encephalitis)
- Stroke
- Sleep disorders
- Memory impairment
An EEG can't measure intelligence or detect mental illness. It may be used to confirm brain death in someone in a persistent coma.
- 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.