Chapter 10

Question 1

interaural time difference (ITD)

Answer 1

The difference in time between arrivals of sound at one ear versus the other.

Question 2

azimuth

Answer 2

The angel of sound source ont he horizontal plane relative to a point in the center of the head between the ears; 0 degrees straight ahead; clockwise.

Question 3

medial superior olive (MSO)

Answer 3

A relay station in the brain stem where inputs from both ears contribute to detection of the ITD.

Question 4

interaural level difference (ILD)

Answer 4

The difference between levels (intensities) of sound at one ear versus the other.

Question 5

lateral superior olive (LSO)

Answer 5

A relay station in the brain stem where inputs from both ears contribute to detection of the interaural level difference.

Question 6

cone of confusion

Answer 6

A region of positions in space where all sounds produce the same time and level (intensity) differences (ITDs and ILDs).

Question 7

directional transfer function (DTF)

Answer 7

A measure that describes how the pinna, ear canal, head, and torso change the intensity of sounds with different frequencies that arrive at each ear from different locations in space (azimuth and elevation).

Question 8

inverse-square law

Answer 8

A principle stating that as distance from a source increases, intensity decreases faster such that decrease in intensity is equal to the distance squared. This general law also applies to optics and other forms of energy.

Question 9

fundamental frequency

Answer 9

The lowest-frequency component of a complex periodic sound.

Question 10

timbre

Answer 10

The psychological sensation by which a listener can judge that two sounds with the same loudness and pitch are dissimilar; timbre quality is conveyed by harmonics and other high frequencies.

Question 11

attack

Answer 11

The part of sound during which amplitude increases (onset).

Question 12

decay

Answer 12

The part of sound during which amplitude decreases (offset).

Question 13

source segregation / auditory scene analysis

Answer 13

Processing an auditory scene consisting of multiple sound sources into separate sound images.

Question 14

auditory stream segregation

Answer 14

The perceptual organization of a complex acoustic signal into separate auditory events for which each stream is heard as a separate event.

Question 15

similarity

Answer 15

Gestalt grofping rule stating that the tendency of two sounds to group together will increase as the acoustic similarity between them increases.

Question 16

common fate

Answer 16

Gestalt grouping rule stating that the tendency of sounds to group together will increase if they begin and/or end at the same time.

Question 17

good continuation

Answer 17

Gestalt grouping rule stating that sounds will tend to group together as continuous if they seem to share a common path, similar to a shared contour for vision.

Question 18

acoustic startle reflex

Answer 18

The very rapid motor response to a sudden sound; very few neurons are involved in the reflex, which can also be affected by emotional state.