Skip to main content
padlock icon - secure page this page is secure

The Helicotrema and the Frequency Resolution in the Inner Ear

Buy Article:

$30.00 + tax (Refund Policy)

The hclicoircina is a transition between the scala vestibule and scala tympani located at the apex of the cochlea. Its impedance influences the travelling waves on the basilar membrane and therefore the frequency encoding in the inner ear. In order to determine these effects a new type of two-dimensional electrical model was used which allows simulation of air-conducted and different modes of bone-conducted hearing as well. The influence of the helicotrema on the travelling waves at low frequency stimulation is not restricted lo regions near the apex, the whole cochlea is concerned. Alterations of the oscillation pattern of the basilar membrane due to a modified impedance of the helicotrema are very complex. The simulations with the electrical model show that optimum frequency resolution by the inner ear might be provided using a relatively small impedance of the helicotrema. Adaption of the travelling waves of various frequencies to the length of the cochlea, and good frequency resolution in a large range are probably the reasons for the relatively large cross-section of the helicotrema in the hearing orguns of mammals.

Zusammenfassung

Das Helicotrema ist eine Verbindung zwischen Scala vestibule und Scala tympani in der Spitze der Gehörschnecke. Seine Impedanz hat Einfluβ auf die Wanderwellen der Basilarmembran und damit auf die Frequenzkodierung im Innenohr. Diese Effekte wurden mit einem neuartigen, zwei-dimensionalen elektrischen Modell untersucht, das sowohl die Simulation von Luftleitung als auch von verschiedenen Anregungsarten durch Knochenleitung ermöglicht. Der EinfluB des Helicotrema auf die Wanderwellen ist nicht auf den Bereich der Cochleaspitze beschränkt, sondern erstreckt sich entlang der ganzen Schnecke. Die Änderungen des Bewegungsmusters der Basilarmembran aufgrund modifizierter Impedanz des Helicotrema sind sehr komplex. Die Simulationen mit dem elektrischen Modell zeigen, daβ eine optimale Frequenzauflösung im Innenohr mit relativ kleiner Impedanz des Helicotrema erreicht werden kann. Die Anpassung der Wanderwellen an die beschrankte Länge der Schnecke in einem weiten Frequenzbereich ist wahrscheinlich die Ursache fur die deutliche Auspragung des Helicotrema bei Säugetieren.

Sommaire

L'hfélicotrfème est un orifice de liaison entre la rampe vestibulaire et la rampe tympanique, situé a l'apex de la cochlée. Son impédance influence la propagation des ondes le long de la membrane basilaire et par conséquent le codage en fréquence de l'oreille interne. Pour évaluer cette influence, nous avons utilisé un nouveau modèle électrique a deux dimensions qui permet de simuler divers aspects de l'audition par conduction osseuse ou aérienne. L'influence de l'h eacute;licotreme sur la propagation en basse frequ eacute;nce ne se limite pas à la zone proche de l'apex, mais concerne l'ensemble de la cochl eacute;e. Les modifications du diagramme de vibration de la membrane basilaire r eacute;sultant d'une modification de l'imp eacute;dance de l'hélicotreme sont tres complexes. Les simulations à l'aide de modèle électrique montrent que l'on obtient une résolution optimale en fréquence dans l'oreille interne avec une valeur relativement faible de l'impédance de l'hélicotrème. L'adaptation des ondes progressives à la longueur réduite de la cochlée sur un large intervalle de fréquencies est probablement liée à la surface relativement grande de l'hélicotrème chez les mammifères.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
No Metrics

Document Type: Research Article

Publication date: September 1, 1994

More about this publication?
  • Acta Acustica united with Acustica, published together with the European Acoustics Association (EAA), is an international, peer-reviewed journal on acoustics. It publishes original articles on all subjects in the field of acoustics, such as general linear acoustics, nonlinear acoustics, macrosonics, flow acoustics, atmospheric sound, underwater sound, ultrasonics, physical acoustics, structural acoustics, noise control, active control, environmental noise, building acoustics, room acoustics, acoustic materials, acoustic signal processing, computational and numerical acoustics, hearing, audiology and psychoacoustics, speech, musical acoustics, electroacoustics, auditory quality of systems. It reports on original scientific research in acoustics and on engineering applications. The journal considers scientific papers, technical and applied papers, book reviews, short communications, doctoral thesis abstracts, etc. In irregular intervals also special issues and review articles are published.
  • Editorial Board
  • Information for Authors
  • Submit a Paper
  • Subscribe to this Title
  • Information for Advertisers
  • Online User License
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more