Auditory Brainstem Response (ABR)
The auditory brainstem response is an auditory evoked potential that originates from the auditory nerve. A “potential” is the electrical activity that can be recorded in the brain; an auditory evoked potential is the electrical activity in the brain that occurs in response to a sound. Electrodes are placed on the head and brain wave activity is recorded while the patient listens to a clicking sound. This test can be used to determine damage to the cochlea, the auditory nerve and the auditory pathways in the brainstem.

Videonystagmography (VNG) – Balance Testing
VNG testing is used to determine if the vestibular portion of the inner ear may be the cause of any balance or dizziness problems. It is one of the only tests available that can determine if a vestibular problem is unilateral or bilateral. The VNG evaluates the function of the vestibular system by recording eye movements, most notably involuntary eye movements called nystagmus. Eye movements are recorded by using special goggles. The three parts of the VNG test include: 1) following a light as it moves in different ways; 2) lying flat on the exam table and moving your head left or right; and 3) stimulating the vestibular system with warm and cool air or water. VNG testing is indicated if a person has complaints of vertigo (spinning), balance dysfunction, gait abnormalities, or when pathology/ disease of the vestibular system is suspected. For more information, please see Balance/Dizziness.

Vestibular Evoked Myogenic Potential (VEMP) Testing
The VEMP is a test that is often performed in conjunction with the VNG evaluation for patients experiencing dizziness or balance problems. The VEMP evaluates additional portions of the inner ear (not evaluated through VNG testing) providing a more complete evaluation of the vestibular system that controls balance. Electrodes are placed on the patients head and neck and a loud sound is delivered through insert earphones. The electrodes measure the response of the balance nerve and a portion of the inner ear to aid in patient diagnosis. For more information, please see Balance/Dizziness.