Auditory Flashcards
What is Hz actually measuring
frequency of sound
high frequency sound has what kind of wavelength
short
low frequency sound has what kind of wavelenggth
long
what is amplitude of sound wave
intesnity of sound
if sound pressure is weaker than reference pressure what will the dB be
negative
what is range of human hearing
20 Hz to 20,000 Hz
People over 25 usually can’t hear above what
~17kHz
What is the most sensitive range of hearing
1-4 kHz
presbycusis
hearing loss in older people
what type of hearing do people lose first
high frequency
What are some things that can cause a notch in audiogram
explosions, gunshots
function of pinna
localizing sound in vertical plane
what is the resonant frequency of the external auditory meatus
3,500 Hz
Function of ossicular system
provide impedance match between outer and inner ear
impendance
resistance to movement
air in outer ear has what kinda impedance
low
fluid in inner ear has what kind of impedance
high
what is the stapedius inenrvated by
CN VII
What is the tensor tympani innervated by
CN V
What is the middle ear muscle attenuation reflex
both muscles contrac tin response to loud noise
HOw can bell’s palsy cause a loss of the middle ear muscle attentuation reflex
by deinnervating the stapedius
What do the middle ear muscles do before vocalization
contract
cochlea
small coiled structure containing the organ of Corti which contains auditory hair cells
endolymph concentrations
high concention of K+
where is endolymph found
in cochlear duct
where is perilymph found
in scala vestibuli, scala tympani and surrounding the lower part of hair cells
what is the conc of perilymph
high Na+ low K+
you is potassium recycled in the cochlea duct
gap junctions
stria vascularis
responsible for production of endolymph
melanocytes are an important component of what
stria vascularis
how is the basialr membrane near the base
narrow and stiff
how is the basilar membrane near the apex
wider and floppy
where are high frequencies in the cochlea
near base
where are low frequencies in cochlea
near apex
binaural interactions
help with sound localization
what is conductive deafness due to
impaired sound transmission in the external or middle ear
What is dearness usually due to
loss of cochlear hair cells
ways that hair cells can be damaged
ototoxic drugs
noise
vestibular schwannoma usually causes what
unilateral hearing loss
what is central hearing loss due to
lesions to central auditory nuclei and pathways
hyperacusis
painful sensitivity to loud sounds
what does spinal ganglion contain
cell bodies
what do outer hair cells help with
more and better frequency discrimination
what is unique about outer hair cells
they can change in length in response to efferent stimulation and sharpen frequency-resolving power of the cochlea
what type of patients don’t usually have otoacoustic emissions
sensory hearing losses of greater than 30 dB
where does the sound lateralize in conductive hearing loss
bad ear
where does sound lateralize in neurosensory hearing loss
good ear
