4.3 - 4.4 Hearing

Question 1

composition of external auditory canal

Answer 1

outer 1/3rd cartilage, contains cerumen glands and hair

inner 2/3rds bony

Question 2

components of the external ear 2

Answer 2

auricle and external auditory canal

Question 3

middle ear area 3

Answer 3

from tympanic membrane to oval window

contains: oscicles of the ear: meatus, incus, stapes

Contains two muscles: tensor tympani and stapedius

Question 4

what do the muscles do in the middle ear

Answer 4

tt = dampens the maleus
s = dampens the stapedius

prevents their vibration during loud noise

Question 5

components of the inner ear 2

Answer 5

bony labyrinth
membranous labyrinth

Question 6

what is the bony labyrinth three thing it contains + 1 other characteristics

Answer 6

contains the cochlea
vestibula and semicircular canals

filled with perilymph

Question 7

what is the scala media contains 3 structures 1 other things

Answer 7

contains the utricle, sacculae and semicircula canal

filled with endolymph

Question 8

cochlea sturctures in order of sound transmission 5

Answer 8

oval window, scala vestibuli, apex, scala tympani, round window

Question 9

three membranes of the scala media

Answer 9

within it has teh basilar membrane, tentorial membrane = fixed and vestibular membrane

Question 10

process of generating signal from scala media 7

Answer 10

vibrations cause basilar membrane to vibrate

its stereocilia bend against fixed tectorial membrane

causes the opening of potassium channels

potassium influx into cells

triggers calcium influx

triggers neurotransmitter release

excitatory synape with spiral ganglia

Question 11

why is there an influx of potassium into stereocilia cells

Answer 11

because endolymph has a high concentration of potassium

Question 12

what is the primary neuron in the auditory pathway

Answer 12

spiral ganglia

Question 13

where is the highest frequeqnecy heard in the cochlear

Answer 13

closest to oval window

Question 13

where is the lowest frequeqnecy heard in the cochlear

Answer 13

apex

Question 13

neural pathway of hearing first two steps

Answer 13

spiral ganglia form the cochlear nerve

goes to brainstem to dorsal and ventral nuclei, here the tract splits into two

Question 13

role of the ventral pathway for sound + where it starts

Answer 13

timing of sound
ventral cochlear nuclues

Question 13

continuation of dorsal auditory pathway 7

Answer 13

dorsal cochlear nucleus
cross at pons
lateral lemniscus
inferior colliculi
LGM of thalamus
internal capsuel + corona radiata
primary auditory cortex

Question 13

role of the dorsal pathway for sound + where it starts

Answer 13

quality of sound

starts in dorsal cochlear nucleus

Question 13

function of utricle

Answer 13

detects linear acceleration in back to forward movement

Question 13

maculae what it contains and what that does

Answer 13

structures which contained crystalised crystals known as otoliths which are in a gelatinous layer

when gravity is applied it pulls on the crystals activating thme,

Question 13

continuation of ventral auditory pathway 6

Answer 13

ventral cochlear nucleus
superior olivary nucleus
lateral lemniscus
inferior colliculus
internal capsule and corona radiata
primary auditory complex

Question 13

function of sacculae

Answer 13

detects linear acceleration in a up and down direction

Question 14

semicircular canals function

Answer 14

there are three: posterior, anterior and lateral

They detect angular forces of acceleration

Question 14

neural pathway of balance (up until nuclei, 3 steps)

Answer 14

vestibular ganglia vestibular nerve vestibular nuclei there are multiple vestibuli nuclei, we will discuss three sets. Lateral ppathway and middle+inferior pathway

Question 14

lateral pathway 2 + function 2 vestibular pathway of balance

Answer 14

lateral vestibular nuclei lateral vestibulospinal tract maintaining balance and extensor tone

Question 14

middle + inferior pathway 3 function 2 vestibular pathway of balance

Answer 14

middle and inferior vestibular nuclei medial vestibulospinal tract terminates at cervical spine function: controlling head and neck movement

Question 14

connections that the vestibular pathway also makes 3

Answer 14

vermis flocculonodular lobe VPL of thalamus

Question 15

sensorineural hearing loss (where it effects =2 and causes = 5)

Answer 15

Damage to inner ear/auditory nerve Causes: aging, prolonged exposure to loud noises, genetics, trauma, infection

Question 16

conductive hearing loss

Answer 16

when sound waves are obstructured/impaired from reaching the inner ear

Question 17

physical exam in hearing loss 4

Answer 17

examination of both years examination of nasopharynx cranial nerve assessment clinical hearing test

Question 18

negative Rhine's test

Answer 18

bone conduction>air conduction indicates conductive hearing loss for affected ear

Question 19

positive rhine's test

Answer 19

air conduction>bone conduction can indicate normal or sensorineural hearing loss

Question 20

positive weber's test in pt w conductive hearing loss

Answer 20

Will go to non functioning ear in conductive hearing loss

Question 21

positive weber's test in pt w neurosensory hearing loss

Answer 21

will go to functinoning ear in neurosensory - that makes sense it wouldn't be heard in non-functioninig ear as that ear doesn't work

Question 22

common causes of vertigo 6

Answer 22

BPPV Meniere's disease labyrinthitis cerebellar stroke medication infection

Question 23

vertigo def dizziness def

Answer 23

illusion of movement of self/environment impairment of spatial perception and stability

Question 24

BPPV def and patho

Answer 24

Benign paroxysmal postural vertigo - brief episodes of vertigo triggered by specific head movements, pathologically due to displacement of canaliths within the semicircular canals

Question 25

Meniere's disease 4 symptoms associated with

Answer 25

disorder of inner ear resulting in: hearing loss, vertigo, sometimes nausea, ear fullness due to endolymph accumulation

Question 26

dix-hallpike maneouvre

Answer 26

positional test used to diagnose BPPV

Question 27

corrective moaneouvre for bppv

Answer 27

Epley maneouvre