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EEG/EMG/Evoked Potential Lab

What you need to know about Electroencephalogram (EEG)

What is an EEG?
An electroencephalogram (EEG) measures the electrical patterns in the brain.

For a routine EEG, what preparation is involved?
There is no preparation for an EEG. You should eat normally and take your usual medication. Do not omit meals unless you are specifically told not to eat. Any hair piece (toupee, weave, hair extensions, etc.) needs to be removed. You will need to register in the Neurophysiology Lab located in the St. Luke's Desloge Outpatient Center, Building B, Suite 22B, approximately 15 minutes prior to your appointment time.

For a sleep EEG, what preparation is involved?
Please do not have anything with caffeine with your evening meal (coffee, tea, soda, chocolate, etc.) the night before your test. Go to bed at your usual time the night before the test. Get up by 2 a.m. the morning of the test; do not go back to sleep after 2 a.m. You need to eat breakfast the morning of the test and take all medications as usual (except sedatives) unless instructed otherwise by the physician. Wear comfortable clothing as you will be sleeping in a recliner - not a bed. The test will take approximately 1 to 1.5 hours to complete.

What happens during the EEG test?
The technician will measure and make marks on your scalp with a wax marker. Small gold plated disks will be attached to the scalp using a washable paste. You will sit in a recliner with your feet up, head back and eyes closed. Avoid talking or moving once the test has begun. Once the electrodes are placed onto the scalp, electrical brain impulses will be recorded. The test will last approximately one hour. This is a painless procedure. After the recording is completed, the electrodes, paste and marks are removed. You are then finished with the test and may leave. The test will be interpreted by a neurologist and results will be sent to your doctor.

After the EEG:
After the test, you may return to your previous activities. Thank you for choosing St. Luke's Hospital for your medical care. Please let the technician know if you have any questions or concerns.

Registration for the tests:
You will need to register approximately 15 minutes prior to your appointment time in the Neurophysiology Lab, located in the St. Luke's Desloge Outpatient Center, Building B, Suite 22B. You should check with your insurance company in advance as to whether you need a referral from your primary care doctor, in order to ensure that the costs of the test(s) will be covered.