Final: Chapter 11 Flashcards
1
Q
For humans, what does hearing provide?
A
signals such as warning sounds, distinctive high-pitched cry of a baby who is distressed, adds richness to our loves through music and facilitates communication by speech.
2
Q
Pressure changes in the air
A
Sound stimulus
3
Q
Pressure changes in the air or other medium.
A
Physical definition of Sound
4
Q
The experience we have when we hear.
A
Perceptual definition of Sound
5
Q
Sound/ sound stimulus
A
Physical stimulus
6
Q
Sound perception
A
Experience of sound
7
Q
Occurs when the movements or vibrations of an object cause pressure changes in air, water, or any other elastic medium that can transmit vibrations.
A
Sound stimulus
8
Q
What happens when the diaphragm of the speaker moves out and it pushes the surrounding air molecules together ?
A
It causes a slight increase in the density of molecules near the diaphragm.
9
Q
The pushing of the surrounding air molecules together
A
Compression
10
Q
What does the increased density of molecules near the diaphragm result in?
A
a local increase in the air pressure above atmospheric pressure.
11
Q
When the speaker diaphragm moves back in, air molecules spread out to fill in the increased space.
A
Rarefaction
12
Q
What does the decreased density of air molecules caused by rarefaction cause?
A
a slight decrease in air pressure.
13
Q
The pattern of air pressure changes that travel through the air at 340 meters per second.
A
Sound Wave
14
Q
TRUE OR FALSE: although air pressure changes move outward from the speaker, the air molecules at each location move back and forth but stay in about the same place.
A
TRUEEEE
15
Q
Occurs when changes in air pressure occur in a pattern described by a mathematical function called a sine wave.
A
Pure Tone
16
Q
The number of cycles per second that the pressure changes repeat
A
Frequency
17
Q
The size of the pressure change
A
Amplitude
18
Q
What is the unit of measure for frequency?
A
Hertz (Hz), where 1 Hz is 1 cycle per second
19
Q
What is one way to specify a sound’s amplitude?
A
indicate the difference in pressure between the high and low peaks of the sound wave.
20
Q
Unit of sound that converts the large range of sound pressures into a more manageable scale
A
decibel (dB)
21
Q
Equation for transforming sound pressure level into decibels
A
dB = 20 * log10 (p/p0)
22
Q
A function or wave that repeats its value at regular intervals.
A
Periodic waveform
23
Q
The repetition rate of a tone/ lowest frequency of a periodic waveform
A
fundamental frequency
24
Q
Tones that are made up of a number of pure tone (sine wave) components added together.
A
Complex tones
25
component of a tone
Harmonic
26
A pure tone with a frequency equal to the fundamental frequency; the first harmonic
Fundamental of a tone
27
Pure tones with frequencies that are whole-number multiples of the fundamental frequency.
Higher harmonics
28
The position of each line on the horizontal axis indicates the frequency of one of the tones' harmonics, and the height of the line indicates the harmonic amplitude.
Frequency spectra
29
What does the frequency spectra provide?
a way of indicating a complex tone's fundamental frequency and harmonics that add up to the tone's complex waveform.
30
Differences in the perceived magnitude of a sound
Loudness
31
Differences in the low to high quality of sounds
Pitch
32
The perceptual quality is most closely related to the level or amplitude of an auditory stimulus, which is expressed in decibels.
Loudness
33
What do thresholds and loudness depend on?
not only decibels but also on frequency
34
- Indicates threshold for hearing versus frequency.
- indicates that we can hear sounds between about 20 Hz and 20,000 Hz and that we are most sensitive at frequencies between 2000 and 4000 Hz.
Audibility curve
35
What is the range of frequencies that is most important for understanding speech?
2000 and 4000 Hz
36
the area above the audibility curve that shows tones we can hear.
Auditory response area
37
Tones within the upper boundary of the auditory response area; these high amplitudes are the ones we can "feel"; they can become painful and can cause damage to the auditory system.
Threshold of feeling
38
the decibels at which it can just barely be heard, as indicated by the auditory curve
baseline (threshold) of a frequency
39
TRUE OR FALSE: loudness increases as we increase the level above this baseline
TRUE
40
Indicate the sound levels that create the same perception of loudness at different frequencies
Equal Loudness
41
How is the equal loudness curve determined?
By presenting a standard pure tone of one frequency and level and having a listener adjust the level of pure tones with frequencies across the range of hearing to match the loudness of the standard.
42
The perceptual quality we describe as "high" or "low", can be defined as the property of auditory sensation in terms of which sounds may be ordered on a musical scale extending from low to high.
- also a property of speech
Pitch
43
The physical property of fundamental frequency
Pitch
44
The repetition rate of the sound waveform
Fundamental frequency
45
Low fundamental frequencies are associated with _____ pitches
Low
46
High fundamental frequencies are associated with _____ pitches
High
47
The perceptual experience of increasing pitch that accompanies increases in a tone's fundamental frequency.
Tone Height
48
Notes with the same letter
Tone Chroma
49
Every time we pass the same letter on the keyboard, we have gone up an interval called an __________.
octave
50
Notes with the same chroma have fundamental frequencies that are separated by a multiple of ______.
Two
51
When the pitch remains the same, even when the missing fundamental or other harmonics are removed.
Effect of the missing Fundamental
52
The quality that distinguishes between two tones that have the same loudness, pitch, and duration but still sound different
Timbre
53
What does timbre depend on?
A tone's attack and the tone's decay
54
The buildup of sound at the beginning of the tone
Tone's attack
55
the decrease in sound at the end tone
Tone's decay
56
The pattern of pressure changes in the waveform repeats/ Pure tones and the tones produced by musical instruments
Periodic sounds
57
Sounds that have waveforms that do not repeat
Aperiodic sounds
58
TRUE OR FALSE: Only aperiodic sounds can generate a perception of pitch
FALSE, periodic sounds do this
59
What are the three basic tasks that the auditory system accomplishes?
First, it delivers the sound stimulus to the receptors; second, it transduces this stimulus from pressure changes into electrical signals; and third, it processes these electrical signals so they can indicate qualities of the sound source, such as pitch, loudness, timbre, and location.
60
What are the divisions of the ear?
outer, middle, and inner
61
Small hairlike parts of the hearing receptors
Stereocilia
62
Sound waves first pass through the _________ ______, which consists of the __________ and the ___________ ________.
The outer ear, pinnae, auditory canal
63
The structures that stick out from the sides of the head; the location of sounds
Pinnae
64
A tubelike recess about 3 cm long in adults protects the delicate structures of the middle ear from the hazards of the outside world, protects the delicate tympanic membrane (eardrum), and helps keep this membrane and the structures in the middle ear at a relatively constant temperature.
Auditory canal
65
Enhances the intensities of some sounds by means of the physical principle of resonance
Auditory canal
66
Occurs in the auditory canal when sound waves that are reflected back from the closed end of the auditory canal interact with sound waves that are entering the canal.
Resonance
67
The frequency that is reinforced the most being determined by the length of the canal.
Resonant Frequency
68
What happens when airborne sound waves reach the tympanic membrane at the end of the auditory canal?
They set it into vibrations, and this vibration is transmitted to structures in the middle ear, on the other side of the tympanic membrane.
69
The ________ ________ is a small cavity that separates the outer and inner; contains the ossicles.
middle ear
70
The smallest bones in the body; the malleus, incus, and stapes
ossicles
71
Known as the hammer; set into vibration by the tympanic membrane, to which it is attached, and it transmits its vibrations to the incus (anvil)
Malleus
72
Known as the anvil, it transmits its vibrations to the stapes.
Incus
73
Known as the stirrup; transmits its vibrations to the inner ear by pushing on the membrane covering the oval window.
stapes
74
Both the outer ear and middle ear are filled with ________.
air
75
The inner ear contains what?
a watery liquid that is much denser than the air
76
What problem does the liquid in the inner ear cause?
pressure changes in the air are transmitted poorly to the much denser liquid.
77
How do the ossicles help solve the problem of vibrations not transmitting directly from the ait in the middle ear to the liquid in the inner ear?
1. by concentrating the vibration of the large tympanic membrane onto the much smaller stapes, which increases the pressure by a factor of about 20.
2. by being hinged to create a lever action.
78
TRUE OR FALSE: Fish have no outer or middle ear
TRUE
79
in the middle ear; the smallest skeletal muscles in the body
Middle-ear muscles
80
What do the middle-ear muscles do?
At very high sound levels, they contract to dampen the ossicles' vibration.
81
What does dampening the ossicles' vibration do?
Reduces the transmission of low-frequency sounds and helps to prevent intense low-frequency components from interfering with our perception of high frequencies.
82
What is the main structure of the inner ear?
The liquid-filled cochlea
83
upper half of the uncoiled cochlea
scala vestibuli
84
lower half of the uncoiled cochlea
scala tympani
85
The structure that separates the scala vestibuli and scala tympani; contains the organ of corti, exteds the entire lenghth of the cochlea
Cochlear partition
86
Where is the base of the cochlea?
near the stapes
87
Where is the apex of the cochlea?
at the far end
88
Contains the hair cells (receptors for hearing)
Organ of Corti
89
What are the two membranes?
the basilar membrane and the tectorial membrane
90
at the tips of the hair cells; bends in response to pressure changes
Stereocilia
91
How many rows of inner hair cells do humans have?
1 row
92
How many rows of outer hair cells do humans have?
3 rows
93
Where is the stereocilia of the tallest row of outer hair cells embedded?
tectorial membrane
94
Where is the stereocilia of the left-over outer hair cells and all the inner hair cells embedded?
NOT on the tectorial membrane
95
What does the back-and-forth motion of the oval window transmit?
vibrations to the liquid inside of the cochlea
96
What are the 2 results of the up-and-down motion of the basilar membrane?
1. it sets the organ of corti into an up-and-down vibration
2. causes the tectorial membrane to move back and forth
97
The main receptors responsible for generating signals that are sent to the cortex in auditory nerve fibers.
inner hair cells
98
Steps of transduction for hearing
1. stereocilia of the hair cells bend in one direction (right)
2. ion channels open in stereocilia
3. Positively charged potassium ions flow into the cell, and an electrical signal results.
99
What does the bending of the stereocilia cause?
causes structures called tip links to stretch, and this opens tiny ion channels in the membranes of the stereocilia; causing alternating bursts of electrical signals
100
What happens when the stereocilia bends in the other direction (left)?
1. tip links slacken
2. ion channels close
3. ion flow stops
4. no energy signals
101
What is the result of the electrical signals in the hair cells?
release of neurotransmitters at the synapse separating the inner hair cells from the auditory nerve fibers, causing auditory nerve fibers to fire.
102
What happens when the pressure increases?
The stereocilia bend to the right, the hair cell is activated, and attached auditory nerve fibers will tend to fire.
103
What happens when the pressure decreases?
The stereocilia bend to the left, and no firing occurs. The auditory nerve fibers fire in synchrony with the rising and falling pressure of the pure tone.
104
The property of firing at the same place in the sound stimulus
Phase locking
105
What does a sound's repetition rate produce?
A pattern of nerve firing in which the timing of nerve spikes matches the timing of the repeating sound stimulus
106
What did Bekesy determine about the basilar membrane? How did he accomplish this?
the basilar membrane vibration of the basilar membrane. He accomplished this by boring a hole in cochleas taken from animals and human cadavers.
107
The motion that occurs when a person holds the end of a rope and snaps it, sending a wave traveling down the robe
Traveling wave
108
As frequency increases, what happens to the place on the membrane that vibrates the most?
it moves from the apex at the end of the cochlea toward the base at the oval window
109
High frequencies cause more vibration near the _____________________.
near the base end of the cochlea
110
Low frequencies cause more vibration near the _____________________.
apex of the cochlea
111
High frequencies activate what part of the cochlea?
base
112
Low frequencies activate what part of the cochlea?
apex
113
map of frequencies
tonotopic map
114
A neuron's frequency tuning curve is determined by?
presenting pure tones of different frequencies and measuring the sound level necessary to cause the neuron to increase its firing above the baseline or "spontaneous rate in the absence of sounds
115
What is the cochlea's filtering action reflected by?
1. neurons respond best to one frequency
2. each frequency is associated with nerve fibers located at a specific place along the basilar membrane
116
Explains why neural turning curves were narrower than what would be expected based on Bekesy's measurements of basilar membrane vibration.
Cochlear amplifier
117
Influences the way the basilar membrane vibrates, and they accomplish this by changing length
outer hair cell
118
What does ion flow in inner hair cells cause?
electrical response in auditory nerve fiber
119
What does ion flow in outer hair cells cause?
mechanical changes inside the cell that causes the cell to expand and contract
120
What causes the outer hair cells to become elongated?
When the stereocilia bend in one direction and contract when they bend in the other.
121
What does the mechanical response of elongated and contraction that pushes and pulls on the basilar membrane cause?
increase in the motion of the basilar membrane and sharpens its response to specific frequencies.
122
What sharpens the tuning of each place along the cochlea?
cochlear amplifier
123
causes a peak of activity at a specific place on the basilar membrane. The neurons connected to that place respond strongly to that frequency.
A pure tone
124
Where does the information from the neurons go to in audition?
Info is carried up to the auditory nerve to the brain
125
What is the brain doing with the information that is carried up the auditory nerve?
The brain identifies which neurons are responding the most and uses this info to determine the pitch
126
Based on the relation between a sound's frequency and the place along the basilar membrane that is activated
Place Theory
127
The idea that pitch can be determined by harmonics only work for ?
low harmonics - harmonics that are close to the fundamental
128
Lower harmonics activate __________ filters, while high harmonics can activate _________ filters.
separate, the same
129
Each lower harmonic can be distinguished by a peak/ bump in the excitation curve
Resolved harmonics
130
The excitations caused by the higher harmonics create a smooth function that does not indicate the individual harmonics.
Unresolved harmonics
131
A stimulus that contains many random frequencies so it doesn't create a vibration pattern on the basilar membrane that corresponds to a specific frequency.
Noise
132
a sound stimulus that wasn't associated with vibration of a particular place on the basilar membrane, but which created a perception of pitch.
Amplitude-modulated noise
133
Means that the level (or intensity) of the noise was changed so the loudness of the noise fluctuated rapidly up and down.
Amplitude modulation
134
Who found that the noise stimulus resulted in a perception of pitch, which they could change by varying the rate of the up-and-down changes in level?
Burns and Viemeister
135
What conclusion did Burns and Viemeister come to?
Pitch can be perceived even in the absence of place information, and has been demonstrated in a large number of experiments using different types of stimuli.
136
what does our experience of hearing depend on?
processing that occurs after signals leave the cochlea
137
What happens to signals generated in the hair cells of the cochlea?
They are transmitted out of the cochlea in nerve fibers of the auditory nerve.
138
Describe the auditory pathway to the brain
It begins in the cochlear nucleus and continues to the superior olivary nucleus in the brain stem, the inferior colliculus in the mid-brain, and the medial geniculate nucleus. From the MGN, fibers continue to the primary auditory cortex in the temporal lobe of the cortex.
139
What does SONIC MG stand for?
SON = superior olivary nucleus
IC = inferior colliculus
MG = medial geniculate nucleus
140
What is processing in the superior olivary nucleus important for?
Locating sounds because it is here that signals from the left and right ears first meet
141
occurs up to about 5000 Hz in auditory nerve fibers, occurs only up to 100-200 Hz in the auditory cortex
Phase locking
142
What did Daniel Bendor and Xiaoqin Wang determine?
How neurons in regions partially overlapping the primary auditory cortex of a marmoset (monkey) responded to complex tones that differed in their harmonic structure but would be perceived by humans as having the same pitch.
143
What did Daniel Bendor and Xiaoqin Wang find?
Neurons that responded similarly to complex tones with the same fundamental frequency but with different harmonic structures.
144
Cortical neurons that responded only to stimuli associated with the 182-Hz tone, which is associated with a specific pitch
Pitch neurons
145
How was brain imaging used?
fMRI to measure the response to stimuli associated with different pitches
146
noise stimulus that covers the same range as the pitch stimulus
Frequency-matched noise
147
What areas are most responsive to pitch?
located in the anterior auditory cortex - the area close to the front of the brain
148
What did Norman-Haignere determine?
in regions most responsive to pitch responded to resolved harmonics but didn't respond as well to unresolved harmonics
149
What did Norman-Haignere conclude?
Since resolved harmonics are associated with pitch perception, this results strengthens the conclusion that these cortical areas are involved in pitch perception
150
What are the causes of hearing loss?
1. noise in the environment
2. damage to the outer hair cells
3. damage to auditory nerve fibers
151
What causes a loss of sensitivity (inability to hear quiet sounds) and a loss of the sharp frequency tuning seen in healthy ears?
damage to the outer hair cells
152
What else could cause of loss of sensitivity besides damage to the outer hair cells?
inner hair cell damage
153
type of hearing loss that is caused by hair cell damage resulting from the cumulative effects over time of noise exposure, the ingestion of drugs that damage the hair cells, and age-related degeneration
Presbycusis
154
TRUE OR FALSE: presbycusis affects females more severely than males
FALSE, it affects males more severely than females
155
type of hearing loss that occurs when loud noises cause degeneration of the hair cells. This degeneration has been observed in examinations of the cochleas of people who have worked in noisy environments. Damage to the organ of corti is present.
Noise-induced hearing loss
156
are activities such as recreational gun use, riding motorcycles, playing musical instruments, and working with power tools.
Leisure noise
157
Hearing loss where people with "normal" hearing who have trouble hearing in noisy environments
Hidden hearing
158
What does the standard hearing test involve?
Measuring thresholds for hearing tones across the frequency spectrum.
159
A plot of hearing loss versus frequency
audiogram
160
hearing loss due to nerve fiber damage has been described as?
hidden hearing loss
161
How can observers tell whether the infant has heard a tone?
They decide by looking for responses such as eye movements, changes in facial expression, a wide-eyes look, a turn of the head, or changes in activity level.
162
How did they determine whether the infant heard a recording of the mother's voice or a recording of a stranger's voice?
By the length of the pause in the infant's sucking.
163
What did DeCasper and Fifer (researchers of infants) find?
the babies regulated the pauses in their sucking so that they heard the mother's voice more than the stranger's voice.
164
What did DeCasper and Fifer (researchers of infants) suggest about why the newborns preferred their mother's voice?
The infants had heard the mother talking during development in the womb
