Audition

Question 1

Through which mechanism do we perceive low-frequency
sounds (up to about 100 Hz)?

Answer 1

At low frequencies, the basilar membrane vibrates in synchrony with the sound waves, and each responding axon in the auditory nerve sends one action potential per sound wave.

Question 2

How do we perceive middle-frequency sounds (100 to
4000 Hz)?

Answer 2

At intermediate frequencies, no single axon fires an action potential for each soundwave, but different axons fire for different waves, andso a volley (group) of axons fires for each wave.

Question 3

How do we perceive high-frequency sounds (above
4000 Hz)?

Answer 3

At high frequencies, the sound causes maximum vibration for the hair cells at one location along the basilar
membrane.

Question 4

What evidence suggests that absolute pitch depends on
special experiences?

Answer 4

 Absolute pitch occurs almost entirely among people who had early musical training and is also more common among people who speak tonal languages, which require greater attention to pitch

Question 5

How is the auditory cortex like the visual cortex?

Answer 5

Any of the following:
(a) Both vision and hearing
have “what” and “where” pathways.
(b) Areas in the
superior temporal cortex analyze the movement of both
visual and auditory stimuli. Damage there can cause
motion blindness or motion deafness.
(c) The visual
cortex is essential for visual imagery, and the primary
auditory cortex is essential for auditory imagery.
(d)
Both the visual and auditory cortices need normal
experience early in life to develop normal sensitivities

Question 6

What is one way in which the auditory and visual cortices
differ?

Answer 6

Damage to the primary visual cortex leaves
someone blind, but damage to the primary auditory
cortex merely impairs the perception of complex sounds
without making the person deaf

Question 7

What kinds of sounds most strongly activate the auditory
cortex?

Answer 7

 Each cell in the primary auditory cortex has a preferred frequency.Many or most cells respond best to complex sounds
that include harmonics. Outside the primary auditory
cortex, most cells respond to “auditory objects” that
mean something

Question 8

Which type of hearing loss would be more common
among members of rock bands and why?

Answer 8

 Nerve deafness is common among rock band members because their frequent exposure to loud noises causes damage to the cells of the ear

Question 9

Which method of sound localization is more effective for
an animal with a small head? Which is more effective for
an animal with a large head? Why?

Answer 9

 An animal with a small head localizes sounds
mainly by differences in loudness because the ears
are not far enough apart for differences in onset time
to be very large. An animal with a large head localizes
sounds mainly by differences in onset time because
its ears are far apart and well suited to noting differences in phase or onset time

Question 9

Which method of sound localization is more effective for
an animal with a small head? Which is more effective for
an animal with a large head? Why?

Answer 9

 An animal with a small head localizes sounds
mainly by differences in loudness because the ears
are not far enough apart for differences in onset time
to be very large. An animal with a large head localizes
sounds mainly by differences in onset time because
its ears are far apart and well suited to noting differences in phase or onset time

Question 9

Which method of sound localization is more effective for
an animal with a small head? Which is more effective for
an animal with a large head? Why?

Answer 9

 An animal with a small head localizes sounds
mainly by differences in loudness because the ears
are not far enough apart for differences in onset time
to be very large. An animal with a large head localizes
sounds mainly by differences in onset time because
its ears are far apart and well suited to noting differences in phase or onset time

Question 9

Which method of sound localization is more effective for
an animal with a small head? Which is more effective for
an animal with a large head? Why?

Answer 9

 An animal with a small head localizes sounds
mainly by differences in loudness because the ears
are not far enough apart for differences in onset time
to be very large. An animal with a large head localizes
sounds mainly by differences in onset time because
its ears are far apart and well suited to noting differences in phase or onset time

Question 10

Sound wave

Answer 10

are periodic compressions of air, water, or other media
they vary in their frequencies and amplitude

Question 11

What are the properties of sound

Answer 11

Amplitude
Frequency
Timbre

Question 12

Amplitude

Answer 12

refers to the intensity of the sound wave

Question 13

Frequency

Answer 13

is the number of compressions per second and is measured in hertz (Hz) Related to the pitch (high to low)

Question 14

Timbre

Answer 14

is tone quality or tone complexity

Question 15

What factors determine the ability to recognize high
frequencies?

Answer 15

Age
Children hear higher frequencies than adults; the ability to recognize high frequencies diminishes with age and
exposure to loud noises

Question 16

Structures of the Ear

Answer 16

Outer ear
inner ear
middle ear

Question 17

Outer Ear

Answer 17

Responsible for:
– Altering the reflection of sound waves into the
middle ear from the outer ear
– Helping us to locate the source of a sound

Question 18

Theories of Pitch Perception

Answer 18

Place theory
Frequency theory

Question 19

Place theory

Answer 19

each area along the basilar
membrane has hair cells sensitive to only
one specific frequency of sound wave

Question 20

Frequency theory

Answer 20

the basilar membrane
vibrates in synchrony with the sound and
causes auditory nerve axons to produce
action potentials at the same frequency

Question 21

Inner Ear

Answer 21

Connects to three tiny bones (malleus, incus, & stapes) that transform waves into stronger waves to the oval window

The oval window is a membrane in the inner
ear: transmits waves through the viscous
the fluid of the inner ear

The inner ear contains a snail-shaped structure called the cochlea contains three fluid-filled tunnels (scala vestibuli, scala media, & the scala tympani)

Question 21

Inner Ear

Answer 21

Connects to three tiny bones (malleus, incus, & stapes) that transform waves into stronger waves to the oval window The oval window is a membrane in the inner ear: transmits waves through the viscous the fluid of the inner ear The inner ear contains a snail-shaped structure called the cochlea contains three fluid-filled tunnels (scala vestibuli, scala media, & the scala tympani)

Question 22

Inner Ear

Answer 22

Connects to three tiny bones (malleus, incus, & stapes) that transform waves into stronger waves to the oval window The oval window is a membrane in the inner ear: transmits waves through the viscous the fluid of the inner ear The inner ear contains a snail-shaped structure called the cochlea contains three fluid-filled tunnels (scala vestibuli, scala media, & the scala tympani)

Question 23

Hair cells in the Ear

Answer 23

Hair cells are auditory receptors that lie between the basilar membrane and the tectorial membrane in the cochlea

Question 24

current pitch theory

Answer 24

current pitch theory combines modified versions of both the place theory and frequency theory: – Low-frequency sounds best explained by the frequency theory – High-frequency sounds best explained by place theory

Question 25

Variations in Sensitivity to Pitch: Amusia

Answer 25

the impaired detection of frequency changes (tone deafness) Associated with a thicker than average auditory cortex in the right hemisphere, but fewer connections from the auditory cortex to the frontal cortex

Question 26

Variations in Sensitivity to Pitch: Amusia

Answer 26

the impaired detection of frequency changes (tone deafness)

Question 27

Variations in Sensitivity to Pitch: Absolute pitch *perfect pitch*

Answer 27

is the ability to hear a note and identify it 1. Genetic predisposition may contribute to it 2. The main determinant is early and extensive musical training

Question 28

Auditory Cortex

Answer 28

The primary auditory cortex (area A1) is the destination for most information from the auditory system Location: in the superior temporal cortex Each hemisphere receives most of its information from the opposite ear

Question 29

Organization of the Auditory Cortex

Answer 29

1. Superior temporal cortex allows detection of the motion of sound 2. Area A1 is important for auditory imagery

Question 30

Functions of the Auditory Cortex

Answer 30

1. Necessary for processing information but not hearing 2. Provides a tonotopic map in which cells in the primary auditory cortex is more responsive to preferred tones 3.

Question 31

what happens if the Primary auditory cortex is damaged

Answer 31

Damage to A1 does not necessarily cause deafness unless damage extends to the subcortical areas

Question 32

Auditory Areas

Answer 32

1. Areas around the primary auditory cortex

Question 33

Hearing Loss types

Answer 33

Conductive or middle ear deafness Nerve deafness or inner ear deafness

Question 34

Conductive/Middle Ear Deafness

Answer 34

Occurs if bones of the middle ear fail to transmit sound waves properly to the cochlea

Question 35

Conductive/Middle Ear Deafness causes

Answer 35

Can be caused by disease, infections, or tumorous bone growth

Question 36

Normal cochlea function

Answer 36

Normal cochlea and auditory nerve allow people to hear their own voice clearly

Question 37

How to treat Conductive/Middle Ear Deafness

Answer 37

Can be corrected by surgery or hearing aids that amplify the stimulus

Question 38

Nerve or Inner-Ear Deafness

Answer 38

Results from damage to the cochlea, the hair cells, or the auditory nerve Can vary in degree Can be confined to one part of the cochlea People can hear only certain frequencies

Question 39

Nerve or Inner-Ear Deafness Causes

Answer 39

Can be inherited or caused by prenatal problems or early childhood disorders

Question 40

Auditory impairment: Tinnitus

Answer 40

Frequent or constant ringing in the ears is experienced by many people with nerve deafness. Sometimes occurs after damage to the cochlea

Question 41

How do age, and attention affect hearing

Answer 41

Brain areas responsible for language comprehension become less active older people have a decrease in the inhibitory neurotransmitters in the auditory portions of the brain

Question 42

what improves listining during speaking?

Answer 42

Attention improves if the listener watches the speaker’s face

Question 43

factors that affect sound localization

Answer 43

Depends upon comparing the responses of the two ears Three cues: – Sound shadow – Time of arrival – Phase difference

Question 44

how humans localize sounds

Answer 44

Humans localize low frequency sound by phase difference and high frequency sound by loudness differences

Question 45

Mechanisms of Sound Localization

Answer 45

they are three High-frequency sounds (2000 to 3000Hz) create a “sound shadow” * Difference in time of arrival at the two ears most useful for localizing sounds with sudden onset * Phase difference between the ears provides cues to sound localization with frequencies up to 1500 Hz

Question 46

Mechanical Senses

Answer 46

The mechanical senses respond to pressure, bending, or other distortions of a receptor Audition is a complex mechanical sense

Question 47

Vestibular Sensation

Answer 47

The vestibular sense: system that detects the position and movement of the head The vestibular organ is in the ear and is adjacent to the cochlea

Question 48

what is Vestibular Organ

Answer 48

Comprises two otolith organs (the saccule and utricle) and three semicircular canals

Question 49

Semicircular canals

Answer 49

are filled with a jellylike substance and hair cells that are activated when the head moves

Question 50

People with damage to the vestibular system have trouble reading street signs while walking. Why?

Answer 50

The vestibular system enables the brain to shift eye movements to compensate for changes in head position. Without feedback about head position, a person would not be able to correct the eye movements, and the experience would be like watching a jiggling book page.