Criteria for a clinical entity (Sydenham & Guttentag)?
1) Unambiguous definition
2) Homogenous group
3) Perceived limitation
4) Facilitation of Diagnosis & intervention
Brainstem pathway for sound?
Medial Geniculate Body
Inferior Colliculus
Lateral Lemniscus
Superior Olivary Complex
Cochlear Nucleus
who is the father of British Medicine?
Thomas Sydenham
What are the names of the three ossicles? and which ossicle connects to the oval window of the cochlea (inner ear)?
Malleus, Incus, Stapes
Stapes connects to oval window
how is the x-value on the audiogram obtained? how is the y-value on the audiogram obtained?
x: selected by the tester
y: modified Hughson-Westlake protocol
What did the Middelweerd (1990) study focus on?
Index Test?
Reference Test?
Speech recognition in noise differences with a normal audiogram
Index: Speech-in-noise testing
Reference: Self report
Why is single-sided deafness a problem?
Head shadow effect reduces high frequency speech sounds as they reach the hearing ear. Voiceless fricatives are the most attenuated.
According to _____ et al 1996 what is evidence based medicine?
Sackett
Evidence based medicine includes individual clinical expertise and the best external evidence.
Which frequency range is found at the base versus the apex of the apex? and in how many Hz?
Base: High frequency
20,000 Hz
Apex: Low frequency
200 Hz
Describe the outer hair cells versus the inner hair cells
OHC : Cylindrical shaped
3 rows
Stretch & shrink motility
5% afferent neurons
IHC: Pear shaped/flax shaped
Single row
No motility
95% afferent neurons
The scatterplots in R & G are measured in which units?
- Analysis 1 was Hz and Hz (Dots on the scatterplot represent each person & what frequency is affected the most)
- Analysis 2 was dB and dB (Dots on the scatterplot represent each person's acoustic gain level)
Why are the low frequencies harder to localize?
Low frequencies have longer wavelengths so they are unattenuated, meaning both ears will hear the sound at the same level, making it difficult to locate the source of the sound.
What are the roots of evidence based medicine according to Greenstone?
Instituted the practice of hand washing and the mortality rate of infants and their mothers dropped
Describe the modiolus.
Extra points if you can say it correctly LOL
Center of the cochlea, hallow core of the cochlea
Contains the spiral ganglion
Pronunciation: mod-eee-o-lus
how do we know that a study is a diagnostic accuracy study?
the study has two groups
there is an index test
there is a target condition
there is a reference standard test
what happens if the target disorder is unclear?
there is no reference standard, then you cannot identify how well the index test is at identifying the disorder.
Steps of termination for ear canal resonance?
Speaker delivers sound to the ear
The sound level is measured just outside the ear
The sound level is also measured in the ear canal
Subtract inside dB SPL - outside dB SPL = dB of gain at _____ Hz
Who determined that ear plugs are better in noise? and when?
Kryter 1946
What are the 3 Scala found in the cochlear?
Extra points if you know the membranes for each.
Scala vestibuli (Reissners membrane)
Scala media (tectorial membrane)
Scala tympani (basilar membrane)
If you are in the ear canal and wanted to get to the oval window, how would you get there?
Go down the EAC, through the TM, past the middle ear, then rip the stapes footplate off
In Middelweerd (1990) what is the significance of the 1dB difference in steady state noise?
- 3 dB difference between groups in monaural fluctuating mask noise, also significantly greater than the 1dB difference that was seen in steady-state noise
- 1dB in signal-to-noise difference in threshold in fluctuating noise represents a 12% score difference in speech intelligibility
In Middelweerd (1990) what is the significance of the 1dB difference in steady state noise?
1dB in signal-to-noise difference in threshold in fluctuating noise represents a 12% score difference in speech intelligibility
What are some of the studies that helped determine the average thresholds in dB SPL?
Extra points for locations :)
Beasley 1940- national survey, Public Health Service
Steinberg 1940- NYC and San Francisco world fair
Glorig et al (1956)- Wisconsin state fair
Draw the ear and label the process of obtaining ear canal resonance.
Refer to Chasity's paper drawing for answer because she can't add a picture on here.
Tympanic membrane (mic 1 medial) through tube into the ear, mic 2 on lateral side of ear. Loudspeaker.
Describe the acoustic reflex arc:
The acoustic reflex involves sound-elicited middle ear muscle contraction via a neural chain comprising of the:
Middle ear, inner ear, CN 8, Cochlear nucleus, ipsilateral or contralateral, Superior olivary complex, CN 7, back down
Acoustic reflexes are recorded using a tympanometer.