Evoked Potentials (EP) may be used to help identify irregularities of the central and peripheral nervous systems. These irregularities are captured by placing EEG electrodes on the scalp and measuring the electrical activity of the brain when a stimulus is applied. This stimulus can be in the form of as flashing lights, sound clicks, or the stimulation of peripheral nerves.

EP may be ordered as a part of the pre-surgical evaluation or during surgery.

The pediatric neurologist may order evoked potential exams based on the area needing to be evaluated and the stimulus. The three different types of evoked potential exams the neurologist may order for your child are:

  1. Visual EP assesses visual nervous system by flashing lights or perhaps a checkerboard screen.
  2. Auditory EP assesses the auditory nervous system by playing sounds via earphones for your child to hear.
  3. Somatosensory EP uses electrical stimulation of peripheral nerves to activate neural structures along the somatosensory pathways of the upper and lower extremities.

What to Expect

Evoked potentials are a non-invasive procedure that is well tolerated by pediatric patients with little pain and require no special preparation. We ask the parents to wash your child’s hair with shampoo only. Please do not use any other hair products including: conditioner, gel, mousse, or oils. The EEG technologist will use glue, called collodion, to apply the electrodes to your child’s scalp and the head will be wrapped.

Once the electrodes are in place, the exam will begin and your child will be asked to watch the flashing lights, listen to clicks, or parts of their arms or legs are stimulated. If all three EP are ordered, the exam can take 1 to 6 hours depending on the ability of the child to remain quiet and relaxed during stimulation.