2018 ASA CB abstract

"Cochlea wave propagation...” These words started off David Kemp's seminal 1978 contribution to auditory biophysics, where he first described "a new auditory phenomenon” [JASA 64(5): 1386-1391]. The impact of this report has transcended numerous disciplines, finding an impressive range of scientific and clinical applications (e.g., monitoring cochlear status to ototoxicity, biophysical models of the cochlea, pediatric hearing screening). One area where this is most readily apparent is the "comparative" one: It appears that animals all across the phylogenetic tree exhibit robust OAE activity. Given broad morphological differences (e.g., cochlear length, presence/absence of a flexible basilar membrane and/or stereovillar hair cells), a comparative otoacoustic approach offers remarkable potential for identifying universal biophysical principles at play. This talk will compare/contrast OAE properties (and the associated implications) across a broad range of groups such as: humans, birds, frogs, lizards, ferrets, non-human primates, tigers, and even insects. Furthermore, by examining OAEs in species where the traditional basilar membrane traveling wave is absent (e.g., reptiles), we stand to gain biophysical insight into the precise role of "wave propagation". Taken together, the enormous impact the otoacoustic approach has had towards understanding the biomechanics of the inner ear speaks to the truly profound nature of the "Kempian" discovery.