THE EAR:HEARING Flashcards
Tympanic membrane is connected to the cochlea by?
3 auditory oscilles: malleus,incus, and stapes
The ____ connect the middle ear to the pharynx
Eustachian Tubes
outer ear?
pinna and ear canal, terminating to: tympanic membrane
where does sound transduction take place?
Cochlea
The frequency of the sound is perceived as__
pitch
The intensity of the sound is perceived as___
volume
3 main structures that make up cochlea
vestibular duct, cochlear duct, and tympanic duct
Vestibular and tympanic structures are all filled with
perilymph fluid
Cochlear ducts are filled with
Endolymph fluid
found on the top of the cochlear duct. separates it from vestibular duct
Reissner’s membrane
found along the bottom of the cochlear duct seprating it from tympanic duct
Basilar membrane
The___ do transduction of sound from pressure waves to APs
hair cells of Organ of Corti
____ opens ion channels ( from mechanical movement to electrical movement)
Movement of stereocillia
Hair cells have ___- projections that can move with sound-induced pressure waves.
Sterocillia
What does the movement of sterocillia cause?
-depolarization: Increased Ca+2 influx= increased Ca+2 in the cytosol= Exocytosis of NT
how many transductions are involved in this process?
5 total: - Mechanical Sound wave - fluid pressure wave - hair-cell electrical signal - Nt-signal = AP's
APs that acrry sound information project to Medulla by__
Vestibulocochlear nerve (CN 8)
APs stages
Medulla-Thalamus-Auditory Cortex (Temporal Lobe)
2 types of vestibular appartus
semi-circular Canals and Otolith Organs
___ of the ear is responsible for our “senses” of balance, equilibrium, and position in space.
Vestibular Apparatus
3 types of semicircular
-posterior, superior, and horizontal canal
senses s head tilt toward shoulder.
posterior canal
senses head rocking front to back, like nodding “yes.”
Superior canal
senses head rotation, like shaking “no.”
Horizontal Canal
Each semicircular canal contain:
Ampulla that hold Cristae
mass of hair cells enclosed in gel mass (cupula)
Crista
Upon movement, the capulla always moves in the ___ direction of movement
opposite
The movement of cappulla in opposite direction pulls ___ to open ion-channels that releases NT
cillia of hair cells
senses linear acceleration and head position
Otolith organs
