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<p>An electroencephalogram (EEG) is a test that detects electrical activity in your brain using small, flat metal discs (electrodes) attached to your scalp. 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.</p><div id='adsmobileBottom'></div>
<p>An EEG is one of the main diagnostic tests for epilepsy. An EEG may also play a role in diagnosing other brain disorders.</p>


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    <span class="moddate">May 20, 2014</span>

<div class="expandable references"><h3><a href="#" class="toggle-open">References</a></h3><div>
<ol>
    <li>Longo DL, et al. Harrison's Online. 18th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=4. Accessed Feb. 15, 2014.</li>
    <li>Neurological diagnostic tests and procedures. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/misc/diagnostic_tests.htm. Accessed Feb. 16, 2014.</li>
    <li>EEG. The Epilepsy Foundation. http://www.epilepsyfoundation.org/aboutepilepsy/Diagnosis/examandtests/eeg.cfm. Accessed Feb. 16, 2014.</li>
    <li>Hirsch LJ, et al. Electroencephalography (EEG) in the diagnosis of seizures and epilepsy. http://www.uptodate.com/home. Accessed Feb. 15, 2014.</li>
    <li>Seizure disorders. The Merck Manuals: The Merck Manual for Health Care Professionals. http://www.merckmanuals.com/professional/neurologic_disorders/seizure_disorders/seizure_disorders.html?qt=eeg&amp;alt=sh#v1037971. Accessed Feb. 16, 2014.</li>
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