Neurophysiology laboratory

An EEG measures electrical signals in your brain. A neurologist will interpret the results and send them to your doctor. Your doctor may schedule an appointment to go over the results with you.

Routine EEG

This test typically takes one hour.

Sleep-deprived EEG

This test will take around 90 minutes. During the test, your awake, drowsy and sleep states will be monitored. Please stay awake the night before your test. You may eat and drink, but you must avoid caffeinated beverages. Please do not drive to or from the test.

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• You do not need to fast before your test. You can continue eating, drinking and taking your regular medications unless your doctor says otherwise.
• Wear comfortable clothing to the test.
• Please come with clean, dry hair that has not been treated with hair products.
• Bring a list of the medications and herbal supplements you are taking.
• Avoid naps, alcohol and caffeine before the test, and follow your doctor’s instructions for the amount of sleep to get the night before.

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The technologist will place a cap on your head and put gel in the electrodes before placing them on your head.

During most of the test, you will lie still and relaxed. The technologist may ask you to open and close your eyes, answer questions, do deep breathing or look at flashing lights.

Once the test is complete, the technologist will remove the electrodes and wash the gel off. You may wish to wash your hair again at home.

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An EP test measures the electrical activity in your brain in response to sight, sound and touch. A neurologist will interpret the results and send them to your doctor. Your doctor may schedule an appointment to go over the results with you.

Visual evoked potentials

You will sit in front of a screen that shows an alternating pattern. If you wear glasses, bring them to this procedure. Allow 30 minutes for the test.

Brainstem auditory evoked potentials

You will hear a series of clicks in each ear. Allow 30 minutes for the test.

Sensory evoked potentials

The technologist will send short electrical impulses to your arms or legs. Allow one to one and a half hours for the test.

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• You do not need to fast before your test. You can continue eating, drinking and taking your regular medications unless your doctor says otherwise.
• Bring a list of the medications and herbal supplements you are taking.
• Wash your hair the night before the test but do not use conditioner or apply hair products.
• Wear comfortable clothing and pants that can be rolled up past the knee.

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We will ask you to remove anything with metal in it (clothing, jewelry, hairpins, eyeglasses, hearing aids, etc.). We will give you a gown to wear if you need to remove clothing.

The technologist will attach electrodes to your head with a paste and ask you to lie on a bed or relax in a chair.

Once the test is complete, the technologist will remove the electrodes and wash the paste off. You may wish to wash your hair again at home.

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