Related Experiment Video
Updated: Jul 17, 2026
05:27
Imaging the Aging Cochlea with Light-Sheet Fluorescence Microscopy
Published on: September 28, 2022
Wave propagation patterns in a "classical" three-dimensional model of the cochlea
Egbert de Boer1, Alfred L Nuttall, Christopher A Shera
1Room D2-226, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
The Journal of the Acoustical Society of America
|February 15, 2007
Summary
This study models cochlear wave propagation and otoacoustic emissions (OAEs) using novel excitation methods. Results show a dominant reverse wave in the cochlea model, aiding OAE generation analysis.
Area of Science:
- Auditory Neuroscience
- Bioacoustics
- Computational Biology
Background:
- Cochlear wave generation and otoacoustic emissions (OAEs) are complex, hindering wave propagation analysis.
- A stylized, nonlinear, three-dimensional cochlear model based on animal data with smooth basilar membrane impedance was utilized.
Purpose of the Study:
- To investigate cochlear wave propagation using unusual excitation methods.
- To simulate distortion product otoacoustic emissions (DPOAEs) and analyze their wave patterns.
Main Methods:
- Applied two novel local excitation methods to a nonlinear cochlear model.
- Simulated DPOAEs by presenting two primary tones (f1, f2) and computed the distortion product (2f1 - f2) response pattern along the basilar membrane.
Main Results:
- Local excitation elicited bidirectional cochlear waves.
- The simulated distortion product wave pattern consistently showed a dominant reverse wave from the f2-tone peak to the stapes.
- Analysis of the distortion product wave components was performed.
Conclusions:
- The nonlinear cochlear model with local excitation effectively simulates wave propagation and DPOAE generation.
- A dominant reverse wave is a key feature in the distortion product response, offering insights into OAE mechanisms.
More Related Videos
Related Concept Videos
01:13The Cochlea
The cochlea is a coiled structure in the inner ear that contains hair cells—the sensory receptors of the auditory system. Sound waves are transmitted to the cochlea by small bones attached to the eardrum called the ossicles, which vibrate the oval window that leads to the inner ear. This causes fluid in the chambers of the cochlea to move, vibrating the basilar membrane.
01:15Auditory Pathway
Auditory pathways constitute the complex neural circuits responsible for transmitting and interpreting auditory information from the peripheral auditory system to the brain. Sound waves are initially captured by the outer ear, funneled through the ear canal, and reach the tympanic membrane (eardrum). These vibrations are transmitted via the middle ear's ossicles to the inner ear's cochlea.
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
01:22Hair Cells
Hair cells are the sensory receptors of the auditory system—they transduce mechanical sound waves into electrical energy that the nervous system can understand. Hair cells are located in the organ of Corti within the cochlea of the inner ear, between the basilar and tectorial membranes. The actual sensory receptors are called inner hair cells. The outer hair cells serve other functions, such as sound amplification in the cochlea, and are not discussed in detail here.
01:16Anatomy of the Ear
Auditory sensation, commonly called hearing, involves the transformation of sonic waves into neural impulses facilitated by the structures of the auditory organ. The prominent, flesh-like structure on the side of the head, called the auricle, directs sound waves towards the auditory canal. The auricle is often mislabeled as the pinna, a term more aligned with mobile structures like a feline's external ear. The auditory canal penetrates the cranium via the external auditory meatus of the...
01:28Standing Waves in a Cavity
A household microwave and lasers are examples of standing electromagnetic waves in a cavity. When two conducting metal plates are placed parallel at the nodal planes, it creates a cavity where standing waves are formed. The cavity between the two planes is analogous to a stretched string held at the points x = 0 and x = L. Here, the distance 'L' between the two planes must be an integer multiple of half of the wavelength. The wavelengths that satisfy this condition are given by:
01:01Sound Waves
Sound waves can be thought of as fluctuations in the pressure of a medium through which they propagate. Since the pressure also makes the medium's particles vibrate along its direction of motion, the waves can be modeled as the displacement of the medium's particles from their mean position.
Sound waves are longitudinal in most fluids because fluids cannot sustain any lateral pressure. In solids, however, shear forces help in propagating the disturbance in the lateral direction as well. Hence,...
Sound waves are longitudinal in most fluids because fluids cannot sustain any lateral pressure. In solids, however, shear forces help in propagating the disturbance in the lateral direction as well. Hence,...