chapter 12: hearing in the environment

Question 1

auditory space

Answer 1

the sounds at different locations around a person

Question 2

localization in vision

Answer 2

images fall on the retina so locations can be easily determined

Question 3

localization in hearing

Answer 3

two different sounds evoke different frequencies in the cochlea, but location information is not transferred

Question 4

location cue

Answer 4

signal or indicator that directs attention or action to a specific location

Question 5

binaural cues

Answer 5

depend on both ears, primarily relies on azimuth (left and right)

Question 6

azimuth (left and right) is associated with what type of cue ?

Answer 6

binaural cues

Question 7

spectral cues

Answer 7

depends on just one ear, primarily relies on elevation (up and down)

Question 8

what are the ways to do binaural cues ?

Answer 8

interaural level different (ILD) and interaural time difference (ITD)

Question 9

interaural level differences (ILD)

Answer 9

best for high frequencies, sound comes from the left, acoustic shadow is on the right side (lower level of sound)

Question 10

interaural time difference (ITD)

Answer 10

best for low frequencies, sound comes from the front, hits both ears at the same time. DOMINANT binaural cue for hearing

Question 11

cone of confusion

Answer 11

sound sources location becomes ambiguous due to identical interaural time and level differences

Question 12

what causes different patterns of frequencies for spectral cues ?

Answer 12

pinna, bumps and grooves in the ear. sound bounces off of them and hits the tympanic membrane

Question 13

what is a way to mess with spectral cues ?

Answer 13

block the ear with something which makes it hard to get spectral cues because the shape of your ear is blocked

Question 14

Jeffress model of auditory localization

Answer 14

circuitry that tells us if the sound comes from the sides or the middle

Question 15

what types of detectors are in the Jeffress model of auditory localization

Answer 15

coincidence detectors (type of ITD detectors), these detectors wait for another input before activating

Question 16

place coding or sparse coding in ITD tuning curves

Answer 16

fine tuned to specific neurons and temporal cues when coming in

Question 17

are ITD turning curves narrow or broad for owls and birds ?

Answer 17

narrow

Question 18

are ITD tuning curves narrow or broad for mammals ?

Answer 18

broad

Question 19

broad waves are ____ in the brain

Answer 19

contralateral

Question 20

when broad sound waves come from the left ear, what hemisphere neurons are activated ?

Answer 20

right hemisphere

Question 21

when broad sound waves come from the right ear, what hemisphere neurons are activated ?

Answer 21

left hemisphere

Question 22

the broad ITD tuning curve being contralateral correlates with what type of coding ?

Answer 22

population coding

Question 23

what cortical regions are involved in localization ?

Answer 23

A1 and primary auditory cortex

Question 24

when information is sent to the parietal lobe, what is being determined ?

Answer 24

where the sound is coming from

Question 25

when information is sent to the temporal lobe, what is being determined ?

Answer 25

what the sound is

Question 26

direct pathway of sound

Answer 26

sound hits nothing before your ear

Question 27

indirect pathway of sound

Answer 27

sound hits something before your ear, time delay is created

Question 28

precedence effect

Answer 28

when there is a time delay in sound, a person perceives only one sound. if the sound delay is too long, the second sound is heard as an echo

Question 29

reverberation time

Answer 29

time it takes for sound to decrease to 1/1000th of its original pressure (decrease by 60 dB)

Question 30

what are the three things that translate to sound quality ?

Answer 30

intimacy time, bass ratio, spaciousness factor

Question 31

intimacy time

Answer 31

direct and first indirect, not time for reflections to die down

Question 32

bass ratio

Answer 32

ratio of low frequencies to middle frequencies reflected off surfaces

Question 33

spaciousness factor

Answer 33

fraction of sound that is indirect only

Question 34

auditory scene analysis

Answer 34

separating each sound

Question 35

what can auditory scene analysis be used for ?

Answer 35

simultaneous grouping and sequential grouping

Question 36

simultaneous grouping includes what ?

Answer 36

location, onset synchrony, timbre and pitch, and harmonicity

Question 37

location in simultaneous grouping

Answer 37

sounds can be separated based on localization cues such as ILD or ITD (these cues help us separate items perceptually)

Question 38

onset synchrony

Answer 38

onset time as a cue for segregation

Question 39

timbre and pitch

Answer 39

sounds are grouped based on same timbre or pitch range, for example a flute vs a trombone

Question 40

harmonicity

Answer 40

when we hear a harmonic series we infer that it came from a single source (a sound with a fundamental frequency and its harmonics)

Question 41

similarity of pitch

Answer 41

usually small intervals separate musical notes and are therefore grouped together (law of proximity)

Question 42

auditory stream segregation

Answer 42

perception of a string of sounds as belonging together

Question 43

alternating in sound impacts what ?

Answer 43

perception

Question 44

slow alteration

Answer 44

one stream alternating

Question 45

fast alteration

Answer 45

two streams (high and low streams)

Question 46

galloping

Answer 46

alternating and then back to the individual sound

Question 47

scale illusion

Answer 47

one scale played in right ear and one played in left ear, but the scales are perceived as two separate scales

Question 48

how are hearing tones and then separated with a space perceived ?

Answer 48

perceived as tones with space

Question 49

how are hearing tones with a noise instead of a space perceived ?

Answer 49

perceived as one continuous tone that is broken up by noise