Sensory System

Question 1

Why is sound localisation important

Answer 1

survival, communication, perception of auditory space

Question 2

What do sensory receptors in hearing form

Answer 2

sound frequency map

Question 3

Binaural hearing

Answer 3

all directions of sounds

Question 4

Monaural hearing

Answer 4

hearing from one side

Question 5

What does binaural hearing lead to

Answer 5

prediction of sound object

Question 6

Cues for sound localisation

Answer 6

sound elevation in vertical plane, monaural cues, head related transfer functions

Question 7

What do monaural cues require

Answer 7

input from one ear

Question 8

Azimuth

Answer 8

sound position in horizontal plane

Question 9

What does sound position in the horizontal plane require

Answer 9

input from both ears

Question 10

Interaural level differences

Answer 10

difference intensity of sound at the two ears

Question 11

What do interaural level differences mainly occur for

Answer 11

higher frequency sounds

Question 12

Interaural timing differences

Answer 12

difference in arrival time of sound at the two ears

Question 13

What do interaural timing differences mainly occur for

Answer 13

lower frequency sounds

Question 14

What are the components of the auditory pathway

Answer 14

cochlear nucleus, superior olivary complex, inferior and superior colliculus, medial geniculate nucleus, auditory cortex

Question 15

What are the two main pathways in the cochlear nucleus

Answer 15

red from VCN and green from DCN

Question 16

Function of the red pathway in cochlear nucleus

Answer 16

sound localisation

Question 17

Function of green pathway in cochlear nucleus

Answer 17

sound recognition

Question 18

Function of superior olivary complex

Answer 18

sound localisation

Question 19

Function of inferior and superior colliculus

Answer 19

integration with non-auditory inputs

Question 20

Function of medial geniculate nucleus

Answer 20

learning and memory

Question 21

Function of auditory cortex

Answer 21

cognition, attention, memory, decision making

Question 22

Sound localisation centres

Answer 22

anterior ventral cochlear nucleus, lateral superior olive, medial superior olive, medial nucleus of trapezoid body

Question 23

What is the first sound localisation nuclei

Answer 23

aVCN

Question 24

What is the superior olivary complex made up of

Answer 24

aVCN, LSO, MSO, and MNTB

Question 25

What does the LSO-MNTB binaural excitatory inhibitory pathway detect

Answer 25

interaural level differences

Question 26

What are interaural level differences encoded by

Answer 26

cells in the LSO

Question 27

Function of cells in the LSO

Answer 27

compare coincidence of excitatory ipsilateral and inhibitory contralateral inputs

Question 28

What do the two LSO act as

Answer 28

broad hemispheric channels

Question 29

What is overall position of a sound encoded by

Answer 29

balance in average output rate of LSO channels

Question 30

True or false - LSOs exist in both sides of the brain and detect ipsilateral sounds

Answer 30

TRUE

Question 31

What pathway detects inter-aural timing differences

Answer 31

binaural excitatory-excitatory pathway - EE

Question 32

What is involved in the EE pathway

Answer 32

VCN and MSO

Question 33

What are ITDs encoded by

Answer 33

cells in MSO

Question 34

What is the function of cells in MSO

Answer 34

compare coincidence of excitatory ipsilateral and contralateral inputs

Question 35

What are ITDs and ILDs represented by in mammals

Answer 35

two broadly tuned channels with balance of output accurately encoding a sound position