Electroencephalogram (EEG)

About Your EEG

An EEG or electroencephalogram is a completely safe and painless procedure for recording the electrical activity produced by the brain. Patterns of the brain's electrical activity provide information about specific brain functions. This information is used to help identify a wide variety of neurological problems. The test usually takes 1 to 1½ hours to perform. Part of this time is spent in applying the electrodes. The actual recording time varies but usually lasts about 30 minutes.

Prior to the Test

  1. So that our technicians can properly apply the electrodes to your scalp, please shampoo your hair the night before the test.  Please remove any hair extensions or additions.  Do not use hair treatment products such as hair spray, conditioners or hair dressing, nor should  you fix your hair in tight braids or corn rows. 
  2. Continue to take your prescription medicine unless specifically instructed by your physician to discontinue use. The technician needs to know what medicines you are taking, so if you take several medications you may want to bring a list of them to the test.
  3. Unless you are instructed otherwise, you should eat normally. However, avoid coffee, tea, sodas, and other drinks and food that contain caffeine.
  4. Please arrive a few minutes early for your test. The quality of the test will improve if you have a chance to relax for a few minutes beforehand.
  5. A special cream is used to attach the electrodes to your scalp during this test. While the technician will clean most of this paste from your hair following the test, you may want to bring a scarf or wig with you as well.

During the Test

The most important things to do during the test are to relax and follow the technician's instructions. Please feel free to ask the technician questions at any time during the test.

  1. We ask that all family and friends, except those who need to translate for the patient, wait in the reception area during the test. If you have to bring children with you, please bring a friend or family member to attend to the small children in the waiting while you are having your test.
  2. While your doctor has given us information concerning your specific problem, the technician will also ask you for certain information that will be helpful to the physician who will interpret your test results.
  3. The technician will then measure and mark the places on your scalp where the electrodes are to be applied. This is done with a special washable crayon.
  4. Next, the technician will scrub each spot with a cleansing solution to ensure proper contact for the electrode. The electrodes will then be attached with a water soluble paste.
  5. During the recording, you will be asked to lie down on an examination table. We will try to make you as comfortable as possible in order to help you relax.
  6. The technician will ask you to open and close your eyes several times during the recording. You might also be asked to perform some special breathing and visual exercises that provide additional information.

After the Test

  1. When the recording is complete, the technician will remove the electrodes and clean the paste from your scalp. A little residue might remain, although the technician will try to remove as much of the paste as possible. The residue will not harm your scalp and will wash away with shampoo.
  2. Your physician will tell you how to obtain your test results. You may resume normal activities immediately.

Special Instructions:

Sleep Deprived EEG

If you are scheduled for a Sleep Deprived EEG, you should have no more than two hours sleep the night before the test and should be awake from midnight the night before your test until test time. Do not drink caffeinated beverages.