Hearing Flashcards
How do sound waves propagate?
As mechanical waves of pressure changes through some medium, with the speed of the wave depending on the medium
How are differences in pressure changes measured?
In sound pressure level (SPL) measured in decibels
How is sound pressure measured?
In micro pascals
What is the auditory response area?
The psychophysically measured area that defines the combinations of frequencies and sound pressure levels (SPLs) over which hearing functions
What is timbre?
The perceived quality that distinguishes between two tones that sound different even though they have the same loudness, pitch, and duration.
How is the quality of transmission maintained in pressure differences going from air to the liquid of the cochlea?
The middle ear contains an amplifier which increases the quality of transmission. Also contains the smallest skeletal muscles in the body which tense as protection against painful sounds.
What is a Fourier analysis?
Breaks complex waveforms into its pure tone components
What is the function of the pinna
To help collect sound from the environment
What are the 3 channels of the cochlea? What is the structure on the whole calles?
- The vestibular, timpanic and middle canals
- Entire structure is the organ of Corti
How is sound perceived?
- Tectorial membrane vibrates according to sound waves
- Outer hair cells connected to the tectorial membrane bend and change the membrane potential
What is a tonotopic map?
An ordered map of frequencies created by the responding of neurons within structures of the auditory system. There is a tonotopic map of neuron along
the length of the basilar membrane of the cochlea, with neurons in the apex responding best to low frequencies and neurons at the base responding best to high frequencies.
How are membranes in the basilar membrane amplified?
By the bending of outer hairs
What is the vestibular system?
The mechanism in the inner ear that is responsible for balance and sensing the position of the body
How is sound localisation (azimuth, distance and eleation) achieved?
Through Interaural Level Difference (ILD) or pressure difference between left and right ear and the Interaural Time Difference (ITD)
Define azimuth
Property of sound that specifies location from left to right
