Also known as: EEG.

What is electroencephalogram?

Electroencephalogram, or EEG, detects brain activity using electrodes attached to the scalp. It is a medical test performed to diagnose epilepsy among other brain disorders.

What happens during the procedure?

The electroencephalogram is fairly simple. A technician marks where to attach the electrodes and then applies the flat medical discs with a special adhesive. Then the patient relaxes with the eyes closed during the test. You may need to perform a few tests, such as looking at pictures or flashing light, performing deep breathing, or doing math problems to stimulate the brain during the test.

Is any special preparation needed?

You may need to avoid any hair product aside from basic shampoo and conditioner before the test. Caffeine should also be avoided.

What are the risk factors?

The only risk of electroencephalogram is the possible triggering of a seizure. No other risks are related to the test.

Reviewed by: Prasanna Jayakar, MD, PhD.

This page was last updated on: March 02, 2020 12:14 PM

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