Lecture 14 - Clinical disorders of the auditory system

Question 1

name the 2 types of hearing loss

Answer 1

conductive and sensorineural

Question 2

in which 2 locations can conductive hearing loss occur? which types of things can cause it?

Answer 2

in middle ear and ear canal, glue ear, wax, otitis media

Question 3

in which 3 locations can sensorineural hearing loss occur?

Answer 3

cochlea, auditory nerve, central pathways

Question 4

which 3 things can cause sensorineural hearing loss in the cochlea?

Answer 4

age, noise damage, drugs

Question 5

which 2 things can cause sensorineural hearing loss in the auditory nerves?

Answer 5

noise overexposure, auditory neuropathies

Question 6

what can cause sensorineural hearing loss in the central auditory pathways?

Answer 6

bilateral strokes

Question 7

at which frequency is there a notch on the graph in noise induced hearing loss?

Answer 7

4 kHz

Question 8

which fibres can be selectively damaged from noise overexposure in cochlear synpatopathy?

Answer 8

high SR fibres

Question 9

which wave of ABR is diminished in cochlear synaptopathy?

Answer 9

wave I

Question 10

give the clinical name for age related hearing loss

Answer 10

presbyacusis

Question 11

name the 3 types of age related hearing loss and the shape of their curves on an audiogram

Answer 11

metabolic - flat
sensory - high frequency slope
auditory nerve - not reflected (similar to cochlear synaptopathy)

Question 12

name an uncommon hearing loss disease which has the reverse shape of the curve of age related hearing loss on a frequency slope

Answer 12

meniere’s disease

Question 13

name 5 signs of homeostatic plasticity/processes in the brain and ear that compensate for hearing loss

Answer 13

loudness recruitment, central gain, central noise, tonotropic map changes, increased use of memory and predictions

Question 14

where does loudness recruitment begin in the ear during homeostatic plasticity?

Answer 14

cochlea

Question 15

increased central gain can be perceived as what to the individual?

Answer 15

tinnitus

Question 16

what does central gain aim to correct?

Answer 16

input from external sounds and internal noise

Question 17

what is the difference between central noise and central gain, giving a condition example for each?

Answer 17

noise = additve, tinnitus
gain = multiplicative, hyperacusis

Question 18

sensorineural hearing loss can be described as reduced flow from the ……… but increased flow to it

Answer 18

the auditory cortex

Question 19

give 3 ways in which hearing loss can be restored

Answer 19

hearing aids, cochlear implant, auditory mid brain implant

Question 20

name 4 clinical disorders resulting from hearing loss

Answer 20

tinnitus, musical hallucinosis, hyperacusis, dementia

Question 21

what are the 4 popular theories of tinnitus brain mechanisms?

Answer 21

central gain, central noise, filling in from auditory memory, altered auditory predictions

Question 22

why does tinnitus remain?

Answer 22

brain must decide whether to accept increased activity in auditory pathway or ignore it as noise, once accepted, brain learns to predict tinnitus hence it remains

Question 23

give an example of a syndrome where muscial hallucinosis is present

Answer 23

charles-bonnet

Question 24

what is hyperacusis?

Answer 24

the experience of moderately loud sounds as uncomfortably loud

Question 25

name 5 factors which hyperacusis is associated with

Answer 25

hearing loss, middle age and older, autism, migraine, neurological disorders