Acoustic nerve and Central Auditory Nervous System
100
Endolymph is found in this scala.
What is scala media?
100
It is flask shaped and has rows of stereocilia protruding from the cuticular plates at its top end.
What is an inner hair cell?
100
Its primary function is to funnel acoustic vibration to the external auditory meatus
What is the auricle? What is the pinna?
100
The external auditory canal ends here, which is considered the beginning of the middle ear.
What is the tympanic membrane? What is the eardrum?
100
The auditory nerve exits the temporal bone through the internal auditory meatus and enters the brainstem at a location called this, which describes the relationship of the pons and the cerebellum in this area.
What is the cerbellopontine angle?
200
The scala vestibuli innervates with the __________ at the _______________ window here.
What is stapes and oval window?
200
These PORES open during excitation (allowing potassium ions into the cell) and close during inhibition.
What are Ion channels? Ion pores?
200
The sebaceous and ceruminous glands are in this portion of the external auditory canal?
What is the cartilaginous portion?
200
The three bones in the ossicular chain?
What are the malleus, incus, and stapes?
200
This systematic organization of frequency by location which is seen at every level of the auditory system.
What is tonotopic organization?
300
A thin membrane that goes from the top of the medial aspect of the limbus to the spiral ligament at an upward angle of about 45°
What is Reissner's membrane?
300
Process which occurs when the stereocilia bend toward the the lateral wall of the duct (towards the spiral ligament ) pulls or stretches the upward pointing crosslink and ...pulling the filament opens a pore (think of opening a trapdoor), on the top of the shorter cilium, which permits ions to flow through it, activating the cell...
What is excitation?
300
Sounds entering the ear will be enhanced if they are close to the resonant frequency range , resulting in a boost in the sound pressure level reaching the eardrum. This is called....
What is the ear canal resonance effect?
300
The function of the middle ear which allows it to overcome the impedance mismatch of sound in air traveling through to fluid in the cochlea
What is impedance matching transformer?
300
Daily double-Short period of exhaustion during which neuron can not respond to stimulation
Two types: 1) No stimulus can be effective in generating a spike (about 1 msec)
1 msec
2)Period during which the nerve’s ability to respond depends on level of succeeding stimulus and therefore
elevates threshold
What is a refractory period?
1) What is the Absolute refractory period
2) What is the Relative refractory period
400
The sensory organ for hearing and sits on top of the basilar membrane
What is the Organ of Corti?
400
The process where the haircells transform mechanical energy from the middle ear to electrical energy in the cochlea
What is transduction? What is a mechanotransducer?
400
A graph or function which shows how the sound reaching the eardrum is affected by the direction of the sound source relative to the head.
What is head-related transfer function?
400
Daily Double:Two muscles in the middle ear which contribute to stiffness within the middl ear cavity? and which nerve innervates them?
What is tensor tympani muscle (CN V Trigeminal) and stapedius muscle (CN VII Facial)?
400
Its sum is the sum of the action potentials of many individual auditory neurons that are firing almost simultaneously within the bundle of auditory nerves.
-is generated by the auditory nerve and can be a good estimate of behavioral hearing threshold.
-It reflects the neural output of the cochlea as information is being sent along the auditory nerve bundle
What is the compound action potential?
500
It arises from the upper lip of the limbus and forms the overlying membrane of the Organ of Corti—it sits on top of the Organ of Corti and the supporting cells of the cochlear duct
What is the Tectorial Membrane?
500
This action of the cilia in the excitatory direction (upward displacement), away from the modiolus, causes an increased influx of potassium and then calcium flowing into the cell which increases the current flow across the hair cell membrane and depolarizes the hair cell
What is the shearing action?
500
The difference between the intensity level of the signal reaching the two ears (one compared to the other)
What is interaural (inter-ear) intensity difference?
500
The force that is exerted over the larger area of the tympanic membranewhich is then transmitted to the smaller area of the oval window– creating a ratio difference of 17:1
What is the area advantage of the middle ear ?
500
The 5 major way stations or pathways of the ascending auditory system in the CNS.
What is the cochlear nucleus, superior olivary complex, lateral leminiscus, inferior colliculus, medial geniculate body?