title: Predicting the location of missing outer hair cells using the electrical signal recorded at the round window.
abstract: The electrical signal recorded at the round window was used to estimate the location of missing outer hair cells. The cochlear response was recorded to a low frequency tone embedded in high-pass filtered noise conditions. Cochlear damage was created by either overexposure to frequency-specific tones or laser light. In animals with continuous damage along the partition, the amplitude of the cochlear response increased as the high-pass cutoff frequency increased, eventually reaching a plateau. The cochlear distance at the onset of the plateau correlated with the anatomical onset of outer hair cell loss. A mathematical model replicated the physiologic data but was limited to cases with continuous hair cell loss in the middle and basal turns. The neural contribution to the cochlear response was determined by recording the response before and after application of Ouabain. Application of Ouabain eliminated or reduced auditory neural activity from approximately two turns of the cochlea. The amplitude of the cochlear response was reduced for moderate signal levels with a limited effect at higher levels, indicating that the cochlear response was dominated by outer hair cell currents at high signal levels and neural potentials at low to moderate signal levels.
authors.affiliation: Department of Hearing and Speech, University of Kansas Medical Center, Kansas City, Kansas 66160.
authors.forename: Mark E
authors.initials: ME
authors.lastname: Chertoff
authors.affiliation: Department of Communication Sciences and Disorders, University of Cincinnati, Cincinnati, Ohio 45267.
authors.forename: Brian R
authors.initials: BR
authors.lastname: Earl
authors.affiliation: Department of Biostatistics, University of Kansas Medical Center, Kansas City, Kansas 66160.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Diaz
authors.affiliation: Department of Hearing and Speech, University of Kansas Medical Center, Kansas City, Kansas 66160.
authors.forename: Janna L
authors.initials: JL
authors.lastname: Sorensen
authors.affiliation: Hearing and Balance Center, Boys Town National Research Hospital, Omaha, Nebraska 68131.
authors.forename: Megan L A
authors.initials: ML
authors.lastname: Thomas
authors.affiliation: Department of Hearing and Speech, University of Kansas Medical Center, Kansas City, Kansas 66160.
authors.forename: Aryn M
authors.initials: AM
authors.lastname: Kamerer
authors.affiliation: Department of Hearing and Speech, University of Kansas Medical Center, Kansas City, Kansas 66160.
authors.forename: Marcello
authors.initials: M
authors.lastname: Peppi
mesh_terms: D000818:Animals; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold; D003055:Cochlear Microphonic Potentials / Q000187:drug effects; D004195:Disease Models, Animal; D005260:Female; D005849:Gerbillinae; D018072:Hair Cells, Auditory, Outer / Q000187:drug effects / Q000473:pathology*; D006317:Hearing Loss, Noise-Induced / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology*; D007834:Lasers; D008954:Models, Biological; D010042:Ouabain / Q000494:pharmacology; D012405:Round Window, Ear / Q000293:injuries / Q000294:innervation*
chemical_list: D010042:Ouabain