(Cochlear Function) Flashcards
chain of events that occur from middle ear to auditory nerve
traveling wave in cochlear duct > basilar membrane displaces > hair cells shear > cili of hair cells bend > chemical release/mechanical release/cochlear microphonic > action potential > to auditory nerve
There’s a _ force and _ of the _ that cause _ innervating the hair cell to _.
There’s a SHEARING force and BONDING of the CILIA that cause NERVE FIBERS innervating the hair cell to FIRE.
Hair cell stereocilia bundles and OHC & IHC bundles demonstrate these 3 properties needed for the cochlear amplifier
Frequency selectivity, provide amplification, have a force generating component (p 498 Katz)
What contributes to the production of OAEs? (Their contributions may be stimulus level dependent)
OHC somatic motility and stereocilia
Reflection or “___” emissions are characterized by___that rotates rapidly with changes in stimulus frequency
“Place-fixed“, phase
Neurons that receive information from our sensory organs (e.g. eye, skin) and transmit this input to the central nervous system are called
Afferent neurons
Neurons that send impulses from the central nervous system to your limbs and organs are called
Efferent neurons
__ pathways carry signals away from the central nervous system
Efferent
This pathway carries signals that your brain sends to tell your body to do something, like blinking
Efferent pathway
These signals come from outside stimuli and tell your brain what they are sensing, such as temperature.
Afferent signals
Neurons that receive information from our sensory organs (e.g. eye, skin) and transmit this input to the central nervous system are called
Afferent neurons
The term sensory/neural is actually a broad one because it suggests that hearing loss is
either sensory (in the inner ear) or neural (on the auditory nerve), although it may, of course, be both.
The inner ear is a
fluid-filled space, interfaced between the middle ear and the
auditory nerve.
The cochlear portion of the inner ear acts as a device to
convert sound into a form of electrochemical energy that transmits info to the brain about the frequency, intensity, and phase of sound waves.
When the basilar membrane within the cochlea moves up and down in response to __ caused by the rocking movement of the __ in the __, the hair cells within the __ are __ stimulating the __.
When the basilar membrane within the cochlea moves up and down in response to fluid displacement caused by the rocking movement of the stapes in the oval window, the hair cells within the organ of Corti are sheared stimulating the auditory nerve.
There are more than three times as many __ than __
There are more than three times as many outer hair cells than inner hair cells.
outer hair cells assist the inner hair cells in detect-ing __ __ __ and __ the __ of the __ __ along the __ __ for __ __ __ allowing for __ __ of __.
These outer hair cells assist the inner hair cells in detecting softer input sounds and sharpen the peak of the traveling wave along the basilar membrane for enhanced frequency specificity allowing for better perception of speech.
What is the function of the ampullae?
The ampullae contain the cristae, which are the end organs of the semicircular canals.
What is the function of the organ of Corti?
OCC is the end organ for hearing and transduces the mechanical energy in the middle ear to an electrochemical code to be transmitted to the brain.
What can be done to treat autoimmune inner-ear disease?
A Numbers of drugs have been tried, including steroids.
How do hair cells stimulate the auditory nerve?
The hair cells located in the OOC transduce mechanical sound vibrations into nerve impulses. They are stimulated when the BM vibrates.
Retrocochlear hearing loss occurs
beyond the cochlea, either along the auditory nerve, in areas of the brain that process speech, or in the central auditory system.
