CH. 2 - Nature of Sound Flashcards
time in sound when medium compresses, causing increased density of molecules and pressure
condensation/compression
time in sound when medium expands, causing decreased density of molecules and pressure
Rarefaction
complete period of compression + rarefaction of sound wave
cycle
a single moment in a cycle during simple harmonic motion
phase
magnitude of sound
intensity
of cycles in a second in sound (speed)
frequency
perception of frequency
pitch
anatomical name for eardrum
tympanic membrane
Three bones that form ossicular chain
Malleus
Incus
Stapes
Part of malleus that attaches to TM
manubrium
The footplate of the stapes fits into the ____ window
oval
what is the function of the middle ear?
increases pressure by decreasing area - makes it possible for sound to go from air to water
what are the two labyrinths of the inner ear?
osseous and membranous
What are the three channels of the cochlea from superior to inferior?
scala vestibuli
cochlear duct (scala media)
scala tympani
__ __ is often called cochlear partition
Scala media
Scala vestibuli and scala tympani meet here at the apex of the cochlea
helicotrema
what are the two membranes that are on the ends of the cochlear duct, and sandwich the Organ of Corti between them
Reissner’s membrane
Basilar membrane
the small membrane over the Organ of Corti that the hairs brush up against when the organ moves
tectorial membrane
central bony pillar of cochlea; blood vessels and nerve fibers go through here
Modiolus
bundles of cell bodies where nerve fibers synapse
nuclei
most of the auditory nuclei in the CANS get their blood supply from offshoots of the ___ artery
basilar
ability to detect faint sound
absolute sensitivity
what hearing sensitivity usually refers to
absolute sensitivity
ability to detect differences/change in intensity, frequency, or other dimension of sound
Differential sensitivity
Usually this is what hearing acuity refers to
Differential sensitivity
level where stimulus or change in stimulus can get picked up by the body
threshold
lowest level at which acoustic signal can be detected
Absolute threshold
smallest diff that can be detected between two signals
Differential threshold
another name for differential threshold
difference limen
what is an audiogram?
graphic representation of threshold of audibility across audiometric frequency range; plot of absolute threshold
what does HL stand for?
hearing level
type of vibratory energy transmitted by pressure waves in air or other media
Sound
3 requirements for sound to exist
Can you reproduce by budding?!
1) SOURCE - Source of vibratory energy
2) ELASTIC - medium that is compressible or elastic
3) PROPOGATES - Disturbance propagates in that medium via sound waves and carry energy away
what does SPL stand for?
sound pressure level
why was the decibel developed?
to make a logarithmic scale more user-friends
twice the frequency of a given frequency
Octave
audiologists test at these frequency intervals
8va and half 8va
fast wave cycles indicate high ___
frequency
high wave peaks indicate high ___
magnitude
waves of motion of an air molecule creates a ___ effect
domino
If a sound has multiple sinusoids or is not a sinusoid, it is considered ___
complex
interaction of intensity and frequency in a complex sound
spectrum
3 functions of outer ear
1) collect and resonate sound
2) assist in sound localization
3) protect middle ear
3 main parts of outer ear
1) auricle/pinna
2) EAM
3) outer layer of TM
path for O2 to get to middle ear, connected to nasopharynx
Auditory/Eustachian tube
end organ of hearing known as the
Cochlea
how many turns does the cochlea have?
2.5
In cochlea, part that starts nearest to middle ear = ____, part that is furthest from middle ear = ____
base; apex
cochlear fluid high in sodium and calcium
Perilymph
___ hair cells are mostly afferent and ___ hair cells are mostly efferent
inner; outer
____ hair cells expand and contract to reduce the intensity for the __ hair cells
outer; inner
Location processing in hearing starts here
Superior olivary complex or SOC
Most people process information in the ___ temporal lobe, which means their ___ ears are critical to sound collection
left; right
capacity of sense organ to detect stimulus
Sensitivity
in audiogram, threshold is
an intensity a patient can hear 50% of the time
When both air and bone conduction appear in the shaded range in an audiogram, this indicates
normal hearing
When both air and bone conduction result in the same amount of hearing loss, this indicates
sensorineural hearing loss (cochlear)
When bone conduction hearing loss is less than air conduction hearing loss, this indicates
Conductive hearing loss (outer and middle ear)
