Auditory Function

Question 0

Tone

Answer 0

Shape of the waveform

-Complex waveforms=music

Question 1

Pitch

Answer 1

Hz=1/sec

Interpretation of the frequency of sound

Question 2

Loudness

Answer 2

db=20log (test pressure/reference pressure)

Measurement of the amplitude of the sound peaks

*Can be negative dBs since it is a reference measurement

Question 3

Basilar membrane of cochlea

Answer 3

Stiff and narrow @ base (high frequency); loose and wide @ apex (low frequency)

-Movement creates pressure in scala tympani relieved @ the round window

Question 4

Prestin

Answer 4

Motor protein on outer hair cells that causes the cells to change in length

-Changes fast enough to keep up with high oscillations of high frequency sounds

Question 5

Intensity

Answer 5

Encoded by:

1. Firing rate
2. Number of afferents firing

Question 6

Frequency encoding

Answer 6

1. Tonotopy- Basilar membrane has intrinsic properties that stimulate hair cells @ specific frequencies
2. Phase locking- AP firing becomes less aligned w/ sound waves @ higher frequencies

Question 7

Horizontal Sound Localization

Answer 7

1. Interaural time delay- Due to sound waves reaching one ear before the other; MSO interprets this info
   (Frequencies 2,000Hz)

Question 8

Cochlear Amplification

Answer 8

Changes in outer hair cell length that increased the sensitivity and frequency selectivity of inner hair cells