Audition

Question 1

amplitude corresponds to ____
frequency corresponds to ____
complexity corresponds to ____

Answer 1

amplitude&raquo_space; loudness
freq&raquo_space; pitch
complexity&raquo_space; timbre

Question 2

if a sound is 1000 times louder than reference, how many dB would it be?

Answer 2

60 dB (log10^1000 = 3 x 20)

Question 3

adult humans detect frequencies between:

Answer 3

20hz to 20 Khz

Question 4

what is the attenuation reflex?

Answer 4

Tightening of the stapedius and tensor tympani in response to loud noises to protect the ear. loss results in hyperacusis

Question 5

tensor tympani is innervated by ____; stapedius by ___

Answer 5

tt&raquo_space; trigeminal

stap&raquo_space; facial

Question 6

in the organ of Corti, stereo cilia deflected away from the kinocilia cause ____ while deflection toward results in ____

Answer 6

away» hyper polarization from K+ channel closing

toward&raquo_space; depolarization from K+ channel opening

Question 7

describe the compartments of the cochlea:

Answer 7

scala media (cochlear duct) separates the scala tympani and scala vestibuli. media contains endolymph; other two compartments contain perilymph. 80 mv difference across them. V & T connected by helicotrema

Question 8

describe the basilar membrane of the cochlea and the where frequencies are localized:

Answer 8

wider and more flexible at apex, stiffer and narrower at base = high frequencies vibrate at base, low frequencies at apex.

Question 9

afferent fibers innervate ____ hair cells, while efferent fibers from the ___ ____ innervate the ___ hair cells. Efferent response is activated in order to:

Answer 9

afferent&raquo_space; inner
efferent from the superior olive&raquo_space; outer
efferent&raquo_space; dampen loud sounds

Question 10

what changes in length do outer hair cells undergo in response to hyper/de polarization?

Answer 10

hyperpolarization&raquo_space; lengthen

depolarization&raquo_space; shortening

Question 11

what is the contractile mechanism of the hair cells on the basilar membrane?

Answer 11

Prestin – motor protein on membrane

Question 12

what is the cochlear amplifier? what are the advantages of this mechanism?

Answer 12

refers to the ability of the basilar membrane to change level of movement in response to levels of sound
advantages: dampen loud sound, drown out background noise and selectivity increase sensitivity to certain pitches

Question 13

dorsal cochlear nuclei are important for detecting ___ while ventral is more for ___

Answer 13

dorsal&raquo_space; frequency

ventral sends signals to superior olive for sound localization

Question 14

describe how sound localization occurs:

Answer 14

below 3 Hz: time delay

above 3 Hz: intensity differences from each ear

Question 15

where are time delays in sound detected?

Answer 15

the medial superior olive: coincidence detectors.

Question 16

where is sound intensity for sound localization detected?

Answer 16

lateral superior olive: neurons stimulated ipsilaterally but inhibited from contralateral ear by inhibitory neurons in the medial trapezoid body.

Question 17

integration of auditory information occurs in the:

Answer 17

inferior colliculus

Question 18

from the inferior colliculus, signals travel to the:

Answer 18

medial geniculate nucleus of the thalamus

Question 19

describe the specalizations of the primary and secondary auditory cortex:

Answer 19

primary: all cells columnar, receive tonotopic (best frequency) info
secondary: combinations of sounds used in vocalizations

Question 20

what is Wernicke’s area?

Answer 20

posterior to primary auditory cortex. important for understanding speech. lesions&raquo_space; jumbling of words and inability to comprehend speech

Question 21

describe the ventral stream

Answer 21

primary auditory cortex and inferior frontal gyrus. specialized for pitch

Question 22

describe the dorsal stream

Answer 22

superior frontal gyrus and superior parietal cortex. specializied for localization of sound

Question 23

What is Broca’s area?

Answer 23

region in frontal cortex critical for producing speech

Question 24

the supra marginal gyrus is important for:

Answer 24

distinguishing meaningful phonemes

Question 25

the angular gyrus is important for:

Answer 25

matching visual information (graphemes) to meaningful phonemes

Question 26

what is the McGurke effect?

Answer 26

coordination of visual and auditory information. if viewing someone speaking ka and listening to a sound pa, hear “ta”

Question 27

tone deafness is associated with abnormalities in which regions of the brain?

Answer 27

inferior frontal cortex and auditory cortex

Question 28

which aspects of sound are processed in the left hemisphere of the brain? the right?

Answer 28

left: rhythm, pitch and familiarity
right: timbre

Question 29

Sensorinueral deafness and conduction deafness can be distinguished by which diagnostic test?

Answer 29

Rinne test. conduction hearing loss&raquo_space; bone conduction heard longer than air conduction