The Inner Ear Flashcards
The inner ear house structures for….
Hearing and Balance
What structures of the inner ear are important for hearing?
Cochlea & Auditory Nerve
What structures are important for balance?
Semicircular & Vestibular Portion of the 8th Nerve
To maintain balance, we rely on input from how many body systems?
Three
What are the body systems we rely input from to maintain balance?
- Visual
- Proprioceptive
- Vestibular
Define “visual” for the vestibular system
It provides vision, light, and help us adjust to our surroundings accordinly
Define “proprioceptive” for the vestibular system
It provides info from supporting structures such as our muscle/tendons
Define “vestibular” of for the vestibular system
It helps us maintain our balance by using gravity and inertia for info
The semi-circular canals provide…
Angular Acceleration
How does our semi-circular canals tell us when we’re turning?
From our otolith
How does the otolith work?
Since it’s organized in different planes, when it moves around the semi-circular canals, it gives stimulation to our brain to know when we’re turning
The utricle/saccule provides ….
Linear acceleration
How does the utricle/saccule work?
It does not involve turning but up/down and fwd/back
Where is the utricle/saccule located?
Between the portion of the semi-circular and cochlea
What are some things we should note about the Auditory Mechanism?
- As we transition from an air-filled space, we enter a fluid-filled cochlea
- Organ of corti is where the action occurs
- THREE rows of outer hair cell
- ONE row of inner hair cells
- Tectorial membrane is where the shearing movement of the stereocilia occurs
- Tonotopically Organized
For the Auditory system, where is the stereocilia located?
On the top of the 3 rows of outer hair cells and 1 row of inner hair cells
For the Auditory system, the tectorial membrane undergoes the shearing action when…
It touches the stereocilia which helps stimulate the shearing action
For the Auditory system, its tonotopically organized …
According to frequency
What does tonotopically organized mean?
Depending on the frequency, one part of the cochlea would respond
For our cochlea being tonotopically organized, how does it relate to the turns on the cochlea?
When we get to the first turn(base), the higher frequencies would respond and then it gets lower in frequencies and spirals down into the apex
What are the structures of the neurons?
Cell body, Axon, Dendrites
What’s the purpose of the neurons?
To carry information in one direction or the other
Afferent carries
Info from the brain to cochlea
Efferent carries
Info from the brain to the cochlea