Middle ear function and cochlear input impedance in chinchilla.
J Acoust Soc Am
; 127(3): 1397-410, 2010 Mar.
Article
en En
| MEDLINE
| ID: mdl-20329840
ABSTRACT
Simultaneous measurements of middle ear-conducted sound pressure in the cochlear vestibule P(V) and stapes velocity V(S) have been performed in only a few individuals from a few mammalian species. In this paper, simultaneous measurements of P(V) and V(S) in six chinchillas are reported, enabling computation of the middle ear pressure gain G(ME) (ratio of P(V) to the sound pressure in the ear canal P(TM)), the stapes velocity transfer function SVTF (ratio of the product of V(S) and area of the stapes footplate A(FP) to P(TM)), and, for the first time, the cochlear input impedance Z(C) (ratio of P(V) to the product of V(S) and A(FP)) in individuals. mid RG(ME)mid R ranged from 25 to 35 dB over 125 Hz-8 kHz; the average group delay between 200 Hz and 10 kHz was about 52 mus. SVTF was comparable to that of previous studies. Z(C) was resistive from the lowest frequencies up to at least 10 kHz, with a magnitude on the order of 10(11) acoustic ohms. P(V), V(S), and the acoustic power entering the cochlea were good predictors of the shape of the audiogram at frequencies between 125 Hz and 2 kHz.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Acústica
/
Chinchilla
/
Cóclea
/
Oído Medio
/
Modelos Biológicos
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
J Acoust Soc Am
Año:
2010
Tipo del documento:
Article
País de afiliación:
Estados Unidos