Quiz 2

  1. Endocochlear potential is the difference between endolymph and perilymph.

  2. The stria vascularis is located on the lateral wall of the scala media

  3. Cochlear microphonic is the AC potential produced from OHCs that appears to "follow" the acoustic stimulus.

  4. Primary difference is endolymph has greater concentration of potassium than perilymph.

  5. The voltage between the endolymph and perilymph is positive (endo > peril)

  6. Cochlear suppression primarily influences the response of the active process.

  7. The stereocilia can be conceptualized as a variable resistor that controls the flow of current through the hair cells.

  8. IHCs partially snip off negatively going deflections (half-wave rectify the signal) while OHCs does positive and negative.

  9. Hair cell transduction channels are slightly open at rest.

  10. A given patch of the BM will be more sensitive to above the CF.

  11. Active cochlear mechanics are found in outer and inner hair in the hair bundle known as "active motor."

  12. The compound action potential is potential produced when many auditory nerve fibers fire simultaneously.

  13. Summating Potential is DC potential produced when IHCs and OHCs are depolarized.

  14. On the otoacoustic emission (OAE) spectrum from distortion-based to reflection-based OAEs, which class of OAE is closest to the reflection end of the spectrum? SPONTANEOUS OAEs.

  15. For tones presented at the CF, the suppressor tone decreases the gain applied to tones at CF especially low levels in an input/output function.

  16. The signal processing of the BM is analogous to a bank of bandpass filters.

  17. Stereocilia tip links will be associated with…

    1. Temporary threshold shifts

    2. Opening of ion channels

    3. Proteins protocadherin 15 and cadherin 23

  18. Transient OAEs for a normal hearing patient will have a time waveform that looks like a downward chirp, where the Hz changes from high to low over time.

  19. What was observed in the cochlea of the human cadavers in von Bekesy's measurements:

    1. The excitation of the basilar membrane is a traveling wave

    2. The tonotopic representation of signals

    3. The bandwidth and shape of the cochlear filters depends on the characteristic frequency.

  20. The interplay between the active and passive processes results in…

    1. Cochlear compression

    2. Level-dependent cochlear tuning

    3. Level-dependent cochlear gain

  21. A patch of the BM can be classified as a linear or nonlinear system by observing how the gain applied by the BM changes with sound level.

  22. The gain between the malleus and the basilar membrane in a healthy animal decreases with increasing stimulus level for sounds near the CF.

  23. Stimulating the basilar membrane with a pure tone at a low intensity results in resonance at the characteristic frequency for that pure tone.  The magnitude and frequency specificity of this resonance is primarily determined by the degree of damping.

  24. The resonant frequency of a patch of the BM is determined by mass and stiffness.

  25. The active process is also known as the cochlear amplifier.

  26. Passive mechanics dominate the cochlea's response at the high sound levels.

Active mechanics dominate the cochlea's response to low sound levels.

  1. Meningoencephalocele is a type of intracranial complication is likely to lead to a herniation of the meninges into the mastoid cavity

  1. Active process is largely responsible for the exquisite sensitivity of the ear to low-level sounds.

  2. The best frequency to which a give patch of the basilar membrane response depends on sound level. At low levels (near threshold) this frequency is called the "characteristic frequency" (CF). At high sound levels frequencies below CF produce the largest response. THE TRANSITION BETWEEN ACTIVE AND PASSIVE COCHLEAR MECHANICS helps explain this shift in best frequency with sound level.

  3. Changing the frequency of a sinusoid results in a change in place of excitation along the BM.

  4. When the active process is compromised the following occurs…

    1. Tuning broadens

    2. Sensitivity decreases

    3. Compressive nonlinearity is reduced

  5. The passive process is responsible for the upward spread of excitation.

  6. Linear BM response growth for stimuli well below the CF is NOT evidence for NL processing in the cochlea.

  7. Mucociliary clearance is a process by which mucosal tissue remove unwanted materials from the body.