Auditory System Flashcards
What connects the outer ear to the tympanic membrane?
Ear canal
The tympanic membrane does what?
Turns acoustic energy into mechanical energy
Which of the 3 bones are connected to the oval window?
Stapes
What is the middle ear filled with?
Filled with air at atmospheric pressure
What is the cochlea filled with?
filled with fluid
This is known as hearing loss from the outer ear to middle ear; reversible
Conductive hearing loss
This is known as hearing loss from cochlea to nerve; irreversible
Sensory-neuro hearing loss
This is known as the physical measure of soune, it’s perception is pitch.
Frequency
What is the auditory pathway?
Cochlea to Brainstem to Cortex
How many people in the US have a hearing impairment?
30 million in the USA
This is known as the perceptual logarithmic function of the physical variable frequency.
Pitch
What’s the common principle to measure pitch?
Octaves
This is known as the smallest change in frequency needed to perceive a change in pitch
two-tone discrimination
This extracts and breaks down signals into smaller frequencies, and then encodes them and sends it to the brain
Cochlea
What are the 3 measures/properties of sound?
- Frequency
- Intensity
- Time
What is the perceptual aspect of intensity?
loudness
This is known as the time difference used for sound organization
Interaural Time Difference (ITD)
What is the maximum ITD in adult humans?
700 microseconds
What are the tasks of the auditory system?
- Resolve intensity
- Resolve frequency
- Localize sound in space
This is known as the hearing organ.
Organ of Corti
Where is the basilar membrane located?
at the bottom of the membrane
How long is the basilar membrane?
33mm
The basal end of the basilar membrane contains what 3 things? What’s it used for?
- Oval window
- Round window
- Tympanic membrane
- used for high frequency, very stiff
The apical end of the basilar membrane is used for? Is it stiff or flexible
low frequency
flexible
What’s the most common type of aging hearing loss?
high frequency hearing loss
The middle ear deals with impedance by matching it. It reduces it an increases force by how much?
1.3 x
What is the size reduction from the tympanic membrane to the stapes?
17x
What two muscle are important in protecting the ear?
Stapedius & Tensor Tympani muscles
This is known as the movement of fluid into and out of the ear due to the lever action of the tympani and oval window
Sound transmission
The loudness of sound other the same as what ?
Broadness of the crest of the traveling wave
Where is the first cross over in the central auditory mechanism?
Superior olive complex
- crosses before it is transmitted to the cortical areas
This map shows an area for specific frequency to be carried from the cortex all the way to the nerve.
Tonotopic map
