Lecture 23 Flashcards
Eight structures that sound waves need to traverse from auricle to the inner ear
1.
2.
3.
4.
5.
6.
7.
8.
- Auricle
- Auditory canal
- Tympanic membrane (eardrum)
- Malleus
- Incus
- Stapes
- Oval window
8.cochlea
Three components that constitute the outer ear
1. ___________: directs sound waves into the auditory canal
2. ___________: links the outer ear to the eardrum
3. ___________: vibrates in response to sound waves
- Auricle
- Auditory canal
- Tympanic membrane
__________ originates from a vibrating object and travels in ________ created by the back and forth vibration of the surrounding air molecules
sound; waves
Ear wax (__________) secretion helps to _________ and __________ the ear canal and prevent the entry of bacteria, water, and foreign objects
cerumen; clean; lubricate
Four components that make up the middle ear:
1.
2.
3.
4.
- Malleus
- Incus
- Stapes
- Oval window
Ossicles play a role in amplifying vibrations _________ the sound wave pressure because…
- the inner ear consists of a ___________ (not air), so the vibrations must transfer into here
increasing; liquid
The two muscles that are associated with the ossicles are the ___________ and __________
- they __________ sound levels by dampening vibration the ossicular chain
tensor tympani; stapedius
- attenuate
Aside from the incus, which structure is in contact with the stapes?
oval window
In the inner ear, there are two interconnected labyrinths: one is the ______________ labyrinth, which is enclosed by the other, the ____________ labyrinth
membranous; bony
Three parts of bony labyrinth:
1. __________: equilibrium
2. __________: equilibrium
3 __________: hearing
- Semicircular canals
- Vestibule
- Cochlea
Liquids of labyrinth:
- Where is perilymph located?
- Where is endolymph located?
- Which one is similar to the composition of CSF?
- inside bony labyrinth
- inside membranous labyrinth
- perilymph
What makes up the membranous labyrinth?
1.
2.
3.
4.
- Semicircular ducts
- Utricle
- Saccule
- Cochlear ducts
Three chambers of the cochlea and the liquid present
1.
2.
3.
- Scala Vestibuli: perilymph
- Scala Media (cochlear duct): endolymph
- Scala Tympani: perilymph
____________= receptor organ for hearing (sensory epithelium)
- located in the ______________ chamber
- two membranes that surrounds it
1. _____________: on top
2. _____________: at the base
Organ of Corti
- scala media (cochlear duct)
1. tectorial membrane
2. basilar membrane
The organ of corti consists of ___________ and ___________
outer hair cells; inner hair cells
___________: they receive descending inputs from the brain to assist with the modulation of IHC function (20,000 cells)
__________: responsible for hearing transmission
outer hair cells; inner hair cells
______________ are responsible for converting mechanical vibrations produced by sound into electrical signals and they are located in the ________________. The terms for the conversion process is called ____________________
Inner hair cells; Organ of Corti; Mechanotransduction
The _____________ movement of the basilar membrane lead to the mechanical bending of the hairs in IHC with the ____________ membrane
upward; tectorial
___________ mechanical deformation of the hair bundle TOWARDS the longer stereovilli causes the ____________ of mechanosensitive channels at the tips of the stererovilli, which allows ____________ leading to ____________. This activates voltage-sensitive _____ channels, causing release of ______________ with NT—> stimulation of the adjacent sensory neuron
Positive; opening; K+ influx; depolarization; Ca2+; synaptic vesicles
_____________ movement of the basilar membrane causes negative mechanical deformation. This causes the K+ channels to __________ which leads to _____________ –> no transmission of hearing signal
downward; close; hyperpolarization
CN ___ (_____________) is responsible for carrying auditory signals from the ear to the brain
Four nuclei associated with the auditory projection pathway in their sequential order
1.
2.
3.
4.
VIII (vestibulocochlear nerve)
1. Cochlear nucleus
2. Superior olive (medulla)
3. Inferior colliculus
4. Medial geniculate (thalamus)
The primary auditory cortex is located in the __________ lobe and it is responsible for conscious perception of sound
temporal
What makes up the vestibular apparatus (system)?
3 semicircular ducts; utricle and saccule (the otolith organs)
The sensory receptors of the vestibular system are ______________ ( in the crista and macula). The ________________ nerve is linked to them
hair cells; vestibular (part of vestibulocochlear)