Flow Phenomena in the Inner Ear

2019 ◽  
Vol 51 (1) ◽  
pp. 487-510 ◽  
Author(s):  
Dominik Obrist
Keyword(s):  
Inner Ear ◽  
Stokes Flow ◽  
High Frequency ◽  
Particulate Flow ◽  
Fluid Structure Interactions ◽  
Steady Streaming ◽  
Flow Phenomena ◽  
Wave Guides ◽  
Gravity Driven ◽  
Unsteady Boundary Layers

A remarkable number of different flow phenomena contribute critically to the proper functioning of the hearing and balance senses, both of which are hosted by the inner ear. This includes quasi-steady and high-frequency Stokes flow, incompressible wave guides, unsteady boundary layers, and fluid–structure interactions between viscous fluids, soft membranes, and hair cell bundles. We present these phenomena, review recent results, and discuss how they relate to the physiology of the vestibular system and the mechanics of hearing. In addition, we study flow phenomena, including gravity-driven particulate flow, magnetohydrodynamics, buoyancy, and steady streaming, that are related to pathologies of the inner ear and relevant to diagnosis and treatment of these diseases.

scholarly journals Hearing from the ocean and into the river: the evolution of the inner ear of Platanistoidea (Cetacea: Odontoceti)

Paleobiology ◽  
2021 ◽  
pp. 1-21
Author(s):  
Mariana Viglino ◽  
Maximiliano Gaetán ◽  
Mónica R. Buono ◽  
R. Ewan Fordyce ◽  
Travis Park
Keyword(s):  
Inner Ear ◽  
High Frequency ◽  
Sound Production ◽  
Marine Species ◽  
Late Oligocene ◽  
Evolutionary Patterns ◽  
Ear Morphology ◽  
Cochlear Morphology ◽  
First Time ◽  
Hearing Abilities

Abstract The inner ear of the two higher clades of modern cetaceans (Neoceti) is highly adapted for hearing infrasonic (mysticetes) or ultrasonic (odontocetes) frequencies. Within odontocetes, Platanistoidea comprises a single extant riverine representative, Platanista gangetica, and a diversity of mainly extinct marine species from the late Oligocene onward. Recent studies drawing on features including the disparate tympanoperiotic have not yet provided a consensus phylogenetic hypothesis for platanistoids. Further, cochlear morphology and evolutionary patterns have never been reported. Here, we describe for the first time the inner ear morphology of late Oligocene–early Miocene extinct marine platanistoids and their evolutionary patterns. We initially hypothesized that extinct marine platanistoids lacked a specialized inner ear like P. gangetica and thus, their morphology and inferred hearing abilities were more similar to those of pelagic odontocetes. Our results reveal there is no “typical” platanistoid cochlear type, as the group displays a disparate range of cochlear anatomies, but all are consistent with high-frequency hearing. Stem odontocete Prosqualodon australis and platanistoid Otekaikea huata present a tympanal recess in their cochlea, of yet uncertain function in the hearing mechanism in cetaceans. The more basal morphology of Aondelphis talen indicates it had lower high-frequency hearing than other platanistoids. Finally, Platanista has the most derived cochlear morphology, adding to evidence that it is an outlier within the group and consistent with a >9-Myr-long separation from its sister genus Zarhachis. The evolution of a singular sound production morphology within Platanistidae may have facilitated the survival of Platanista to the present day.

Effects of Otitis Media on Extended High-Frequency Hearing in Children

1993 ◽  
Vol 102 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Robert H. Margolis ◽  
Joni R. Rykken ◽  
Lisa L. Hunter ◽  
G. Scott Giebink
Keyword(s):  
Inner Ear ◽  
Otitis Media ◽  
Middle Ear ◽  
High Frequency ◽  
Good Test ◽  
Recurrent Otitis Media

Extended high-frequency (EHF) hearing was studied in children with and without histories of chronic or recurrent otitis media (OM). The EHF thresholds were found to have good test-retest repeatability. Children with OM histories had poorer EHF hearing than children without OM histories. The EHF hearing in OM children appeared to be related to OM severity. Children with residual tympanometric abnormalities had poorer EHF hearing than OM children with normal middle ear function. The results suggest evidence for middle ear and inner ear components of EHF hearing losses in children with OM.

scholarly journals Inner-Ear Morphology of the New Zealand Kiwi (Apteryx mantelli) Suggests High-Frequency Specialization

2012 ◽  
Vol 13 (5) ◽  
pp. 629-639 ◽  
Author(s):  
Jeremy R. Corfield ◽  
M. Fabiana Kubke ◽  
Stuart Parsons ◽  
Christine Köppl
Keyword(s):  
New Zealand ◽  
Inner Ear ◽  
High Frequency ◽  
Ear Morphology

scholarly journals A Meshless Boundary Method for Computation of Stokes Flow with Particles in the Semicircular Canals of the Inner Ear

PAMM ◽  
2010 ◽  
Vol 10 (1) ◽  
pp. 459-460 ◽  
Author(s):  
Francesco Boselli ◽  
Dominik Obrist ◽  
Leonhard Kleiser
Keyword(s):  
Inner Ear ◽  
Stokes Flow ◽  
Semicircular Canals ◽  
Boundary Method

A Comparison of the Roughness Regimes in Hydrodynamic Lubrication

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
John Fabricius ◽  
Afonso Tsandzana ◽  
Francesc Perez-Rafols ◽  
Peter Wall
Keyword(s):  
Asymptotic Behavior ◽  
Stokes Flow ◽  
High Frequency ◽  
Reynolds Equation ◽  
Pressure Field ◽  
Hydrodynamic Lubrication ◽  
Narrow Gap ◽  
Surface Textures ◽  
Lubrication Regimes ◽  
Generalized Reynolds Equation

This work relates to previous studies concerning the asymptotic behavior of Stokes flow in a narrow gap between two surfaces in relative motion. It is assumed that one of the surfaces is rough, with small roughness wavelength μ, so that the film thickness h becomes rapidly oscillating. Depending on the limit of the ratio h/μ, denoted as λ, three different lubrication regimes exist: Reynolds roughness (λ = 0), Stokes roughness (0 < λ < ∞), and high-frequency roughness (λ = ∞). In each regime, the pressure field is governed by a generalized Reynolds equation, whose coefficients (so-called flow factors) depend on λ. To investigate the accuracy and applicability of the limit regimes, we compute the Stokes flow factors for various roughness patterns by varying the parameter λ. The results show that there are realistic surface textures for which the Reynolds roughness is not accurate and the Stokes roughness must be used instead.

scholarly journals Downsloping High-Frequency Hearing Loss Due to Inner Ear Tricellular Tight Junction Disruption by a Novel ILDR1 Mutation in the Ig-Like Domain

PLoS ONE ◽  
2015 ◽  
Vol 10 (2) ◽  
pp. e0116931 ◽  
Author(s):  
Nayoung K. D. Kim ◽  
Tomohito Higashi ◽  
Kyoung Yeul Lee ◽  
Ah Reum Kim ◽  
Shin-ichiro Kitajiri ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Tight Junction ◽  
Inner Ear ◽  
High Frequency ◽  
High Frequency Hearing Loss ◽  
Tight Junction Disruption

scholarly journals Nonlinear low-frequency gravity waves in a water-filled cylindrical vessel subjected to high-frequency excitations

2013 ◽  
Vol 469 (2153) ◽  
pp. 20120536 ◽  
Author(s):  
Chunyan Zhou ◽  
Dajun Wang ◽  
Song Shen ◽  
Jing Tang Xing
Keyword(s):  
Gravity Waves ◽  
High Frequency ◽  
Water Waves ◽  
Large Amplitude ◽  
Low Frequency ◽  
Approximation Model ◽  
Fluid Structure Interactions ◽  
Governing Equations ◽  
Low Frequencies ◽  
Nonlinear Fluid

In the experiments of a water storage cylindrical shell, excited by a horizontal external force of sufficient large amplitude and high frequency, it has been observed that gravity water waves of low frequencies may be generated. This paper intends to investigate this phenomenon in order to reveal its mechanism. Considering nonlinear fluid–structure interactions, we derive the governing equations and the numerical equations describing the dynamics of the system, using a variational principle. Following the developed generalized equations, a four-mode approximation model is proposed with which an experimental case example is studied. Numerical calculation and spectrum analysis demonstrate that an external excitation with sufficient large amplitude and high frequency can produce gravity water waves with lower frequencies. The excitation magnitude and frequencies required for onset of the gravity waves are found based on the model. Transitions between different gravity waves are also revealed through the numerical analysis. The findings developed by this method are validated by available experimental observations.

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