Otoacoustic emissions evoked by low-level transients (TEOAE) and single tones (SFOAE) appear to excite the same emission mechanism, a concept originally formulated by Kemp and others and confirmed quantitatively by Kalluri and Shera (JASA 121:20972110, 2007). We have studied emissions evoked by single tones (SFOAE) measured using the suppression method. In humans, 50-70 dB SPL tones most readily suppress SFOAE evoked by lower-level tones when the suppressor is near the frequency of the evoking tone, suggesting that most of the emission originates near the peak of mechanical activity induced by the evoking tone. However, in chinchillas, Mongolian gerbils and mice, emission components originating basal to the peak appear to be relatively larger than in humans. The range of frequencies evoking the largest SFOAE correspond to those where spontaneous emissions are detected, from roughly 0.5 - 6 kHz in humans, 4-12 kHz in chinchillas, 15-30 kHz in mice and still higher in bats. Stimulus tones below this ''hot'' frequency range appear to generate the largest SFOAE components basal to the peak. The existence of ''hot regions'' in the cochlea may explain the apparent species differences in emission behavior between humans and small mammals.
|Title of host publication||Proceedings of the Second ASA-EAA Joint Conference on Acoustics '08|
|State||Published - 2008|
|Event||The Second ASA-EAA Joint Conference on Acoustics '08 - Paris, France|
Duration: Jun 1 2008 → …
|Conference||The Second ASA-EAA Joint Conference on Acoustics '08|
|Period||6/1/08 → …|