chapter ten

Question 1

stereopsis

Answer 1

using two eyes to infer depth

Question 2

sound localization

Answer 2

using two ears to infer the location of an object

Question 3

interaural time difference

Answer 3

The difference in time between the arrival of sound at one year versus the other year. This reliably depends on the azimuth of the sound.

Question 4

interaural level difference

Answer 4

the difference between the sound amplitude between two ears

Question 5

Cone of confusion

Answer 5

Any sound source lying on the perimeter of this cone will produce an identical interaural time/level difference

Question 6

Head movement

Answer 6

We can move our heads around us to help localize sounds

Question 7

relative intensity

Answer 7

Given two sounds, the loud sound is likely closer to you than the farther sound

Question 8

how long is the interaural time difference?

Answer 8

300 microseconds

Question 9

inverse square law

Answer 9

For each doubling distance, the decibel level decreases by 6 dB

Question 10

Spectral content

Answer 10

Low frequencies carry better than high frequencies, thus fewer higher frequencies likely mean the sound is further away

Question 11

Hearing loss

Answer 11

30 million Americans have some level of hearing loss. It gets common as you get older

Question 12

Causes of hearing loss

Answer 12

Blockage of canal
Conductive hearing loss
Sensoneural hearing loss

Question 13

Blockage of canal

Answer 13

Excessive earwax or other debris blocks canal and attenuates sound waves hitting to panic membrane

Question 14

Conductive hearing loss

Answer 14

The tympanic membrane and/or ossicles are damaged, preventing the cochlea from receiving sound waves

Question 15

sensoneural hearing loss

Answer 15

Hearing is lost due to damage to the cochlea or auditory nerve

Question 16

Source segregation

Answer 16

Processing an auditory scene, consisting of multiple sounds into distinct, auditory events or objects

Question 17

Timbre

Answer 17

The ability to judge that two complex sounds with the same fundamental frequency as different. This is due to harmonics and high frequencies from different sources.

Question 18

How does the auditory system localize sounds?

Answer 18

It uses simple, but clever tricks

Question 19

What type of processing is auditory perception?

Answer 19

Top-down processing

Question 20

What are the tricks that the auditory system uses to localize sounds?

Answer 20

1. By frequency similarity.
2. group by timbre
3. group by onset time

Question 21

group by timbre

Answer 21

When we hear multiple sounds
sources, we can try to isolate
them by their timbre

Question 22

group by onset time

Answer 22

We can also group objects by the order that they ”appear” in the auditory stream. separation has to be at least 30ms. musicians accompany this by having different instruments play at different moments