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Electroencephalogram (EEG)

An EEG or electroencephalogram (e-lek-tro-en-sef-ah-lo-gram) is a recording of the electrical activity of the brain.

Before the EEG

There are a few steps that are important to know before coming to the hospital for an EEG.

• Explain the test to your child. You may find helpful resources on YouTube.
• Shampoo your child's hair the night before the test. Do not use any hair spray, oil, or mousse. Remove any hair extensions or weaves that will prevent access to the scalp.
• Your child may eat and drink as usual. They should take any prescribed medications.
• You may bring your child's favorite toy and / or security item such as a blanket.
• If your baby is fed prior to the test, it will be easier for them to fall asleep.

For a sleep-deprived EEG, put your child to bed at their normal bedtime. Then, wake your child at the following suggested times:

• Under 3 years old: Limit sleep to no more than eight hours. Awaken at least two hours prior to the scheduled time.
• 3-11 years old: Limit sleep to no more than six hours. Awaken at least two hours prior to the scheduled time.
• 12 years and older: Sleep from midnight to 4 am.

For a routine EEG:

• Under 2 years old: Put your child to bed at their normal time. They should take no naps prior to the test.
• 2 years and older: Keep your child up two hours past their regular bedtime the night before. Do not allow any naps prior to the test.
• For children under 1 year of age: Do not allow them to nap within two hours of the test, if possible.

How an EEG is Performed

There are several steps that happen before the EEG can be done.

• Electrodes (referred to as buttons, with wires) are put on specific areas of the child's head. A thick paste is used with the electrodes.
• Your child will not be sedated (given medicine to make them sleepy) during the EEG test. So, they may be wrapped snugly (swaddled) in blankets or placed on a papoose board while the electrodes are being placed. A papoose board is designed for young children to lie on and hold them still. The papoose is used to limit movement and avoid inaccurate placement or pulling of the wires during hook-up.
• Next, several small areas of your child's scalp will be prepared for the test by gently scrubbing with a Q-Tip^® and a mild cleanser.
• The “buttons” are then attached to the scalp using the conducting paste.
• The study takes up to 90 minutes.

During the EEG

Once your child is ready for the EEG and the electrodes are in place, you may hold your child. The technologist will let you know what needs to happen at each step of the study.

• Two additional people are allowed in the EEG testing room. Other visitors are asked to wait in the waiting room.
• During part of the test, your child will be asked to keep their eyes closed while a bright flashing light will be used for 10 seconds. This happens several times.
• The technologist may also ask your child to breathe deeply for two to three minutes during the test.
• Your child will need to lie very still and try to relax. We encourage your child to sleep during recording.

After the EEG

Once the EEG is complete, the electrodes will be taken off, and your child may need to have their hair washed again at home. The conducting paste easily washes out with warm water and shampoo. After the test, your child can go back to their normal activities.

A neurologist, a doctor who specializes in the nervous system, will read the tracing (the recording of the brain’s electrical activity). A report will be sent to the requesting doctor or clinic. Results can take three to five business days.