What is an EEG?

An Electroencephalogram, commonly referred to as an EEG, is a test that is used to detect electrical brain activity irregularities. The test monitors basic waveform in addition to measuring the brain’s reaction to certain stimuli, for example, flashing lights.

Why is an EEG Ordered?

If a neurologist suspects that a brain disorder of any type is the cause of symptoms the patient is having, an EEG is one of the most useful diagnostic tools. For example, spikes on the printouts of the brain activity are a key indicator of epilepsy. Brain lesions can often be identified through the very slow EEG waves in test results. When a person has symptoms of Alzheimer’s disease or narcolepsy, EEG testing can be extremely helpful in making the diagnosis. If a patient was in an accident that may have resulted in brain injury, the EEG may be ordered as a way to determine whether there was brain damage.

What is the Preparation Process For an EEG?

Prior to the EEG, the neurologist will review the preparation procedure with each patient. Certain medications may have to be discontinued before having the EEG. Ideally, patients will cease caffeine consumption a minimum of 8 hours before having an EEG test. Any other food and beverage consumption is usually fine and, in fact, it is good to have stable blood sugar levels during an EEG. If the EEG test is related to sleep disorders, the doctor may give the patient specific instructions on how much to sleep before the test.

What About After an EEG?

After an EEG, there are generally no lingering effects of the test. The patient can typically go back to their usual routine whenever they are ready to do so. The neurologist will review the results carefully to gather the necessary information and will then review them with the patient.

Instructions for EEG – Electroencephalogram

On the day of your EEG

  • We will be recording your brain activity for 20 mins. Please keep hair clean. No hairspray, mousse, gel, ponytails, braids, hats, etc. If you fail to keep hair clean for your test, you may need to reschedule your appointment for another day
  • Electrodes will be connected to your head. It is important to keep surface of your head clean for best results. No earrings, lotion or makeup on forehead. No caffeine, such as coffee, tea, soda, or high sugars, etc. You do NOT need to fast. It is ok to have food before your test.
  • Please have children (or anyone advised) come in sleep deprived. Try to put them to bed around midnight and wake them up by 4am. They should have no more than 4 hrs. of sleep the night before test. They will be able to sleep once they come in. (Also, try to keep them up during the drive here.) If you have been advised to be sleep deprived and you have had more than 4 hrs. of sleep, you must contact office ASAP and re-schedule your appt. for another day.
  • Remember, there is no pain involved during this test. Please allow 1 hour for this test.

If you need to reschedule the test or have any questions, please call our office at least 24 hrs. prior to your appt. at (909) 255-6518. If the office is closed at the time you call, you may leave a message with our answering service. Thank you!

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