SPHHRNG 2230 Lecture Notes - Lecture 7: Auditory Brainstem Response, Conductive Hearing Loss, Tympanometry

• School: Ohio State University
• Department: Speech and Hearing Science
• Course: SPHHRNG 2230
• Professor: Evelyn M.Hoglund

Document Summary

Shs 2230 (9/14/15: auditory brainstem response (abr) When a sound is heard, various locations in the brainstem generate measureable electrical potentials. If the waves are late, can be indicator of lesion location. Wave one- through cochlea and onto brainstem. Wave 3- across auditory nerve and to brain step. Wave 5- up brain stem and to midbrain. Used to test infant hearing, since process is totally passive. Used for possible injuries/abnormalities of the auditory nerve or brainstem: tumors, de-myelinating diseases, auditory neuropathy. In cases of serious concern about auditory nerve tumor or unusual middle ear pathology, imaging tests are used for differential diagnosis. Outer hair cells generate distortion sounds that can be measured. Presence of these sounds indicate healthy ohc. Tested in infants, since its faster and cheaper than abr. Excessive cerumen: otoscopy reveals it, flat tympanogram with low ear canal volume (sound doesn"t reach tympanic membrane because blockage, conductive hearing loss.