The effect of contralateral stimulation on cochlear resonance and damping in the mustached bat: the role of the medial efferent system.
Hear Res
; 86(1-2): 111-24, 1995 Jun.
Article
em En
| MEDLINE
| ID: mdl-8567408
ABSTRACT
In the unanesthetized mustached bat, stimulation of the ear with an acoustic transient produces damped oscillations which are evident in the cochlear microphonic potential. In this report we demonstrate how the decay time of these oscillations is affected by broadband noise presented to the contralateral ear (CLN). In the absence of CLN, the mean decay time was 1.94 +/- 0.23 ms, but during the presentation of CLN the decay time consistently decreased. The changes were finely graded, the higher the CLN, the greater the change. The effect could be maintained at a constant level for extended periods of time and this was evident when the CLN exceeded 40 dB SPL. The latency of the reflex for 64 dB noise was about 11 ms and near maximum changes occurred within 15 ms of CLN onset. Sectioning medial efferent nerve fibers in the floor of the fourth ventricle or the administration of a single dose of gentamicin eliminated changes produced by CLN. The prominence of CM responses to damped oscillations and the robust changes in response to CLN make the mustached bat an excellent model for studying the influence of the medial efferent system on cochlear mechanics.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Estimulação Acústica
/
Cóclea
/
Potenciais Microfônicos da Cóclea
/
Neurônios Eferentes
Limite:
Animals
Idioma:
En
Revista:
Hear Res
Ano de publicação:
1995
Tipo de documento:
Article
País de afiliação:
Estados Unidos