Chapter 12 - Music and Speech Perception

Question 1

How fast can we understand speech rates in our native language?

Answer 1

Up to 50 discrete sound units per second

- even though speech in general can only be processed at 12 units per second

Question 2

What is the goal of speech perception?

Answer 2

to develop a meaningful representation of what a speaker

intended to say

Question 3

What are phonetics?

Answer 3

How each speech sound is

produced

Question 4

What are phonemes?

Answer 4

How specific sounds distinguish words in a language

- Smallest unit of language that, if changed, would change the meaning of the word

Question 5

How many phonemes are there in English?

Answer 5

About 40

Question 6

What two types of sounds can the vocal tract produce?

Answer 6

• consonants

- vowels

Question 7

Describe the process of speech production?

Answer 7

1. Respiration (lungs)
2. Phonation (vocal chords)
   ‣ Vibration of the vocal chords
3. Articulation (vocal tract)
   ‣ Movement of the articulators (lips, tongue body and tip,
   jaw)
   ‣ Closing - Consonants
   ‣ Opening - Vowels

Question 8

Why do humans have the largest vocal range in the animal kingdom?

Answer 8

Because the larynx is located much lower in the vocal tract, allowing us to produce more sounds due to the flexibility of vocal chords but makes us more vulnerable to choking

Question 9

What are formants?

Answer 9

A resonance of the vocal tract
‣ Formants are specified by their
frequency and are denoted by
integers that increase with
relative frequency
‣ The first and second formants
are most important for sound
categorization

Question 10

What is the fundamental frequency?

Answer 10

the lowest frequency produced by the oscillation of the whole of an object, as distinct from the harmonics of higher frequency.

Question 11

What is a harmonic?

Answer 11

an overtone accompanying a fundamental tone at a fixed interval, produced by vibration of a string, column of air, etc., in an exact fraction of its length.

Question 12

What is vowel creation dependent on?

Answer 12

Depends largely on the position
and height of the tongue
- Rounding of the lips also affect
vowel production

Question 13

What is a spectrogram?

Answer 13

In sound analysis, a three dimensional display that plots time on the horizontal axis, frequency on the vertical
and amplitude on a colour (or grayscale)
- sounds that may sound similar sometimes have different spectral representations

Question 14

How are consonants classified?

Answer 14

1. Voicing - Vibration of vocal cords that
follows the onset of airflow
a) Voiced consonants
‣ Vibrating vocal cords
‣ ‘b’, ‘m’, ‘z’, ‘l’, ‘r’
b) Voiceless consonants
‣ Non-vibrating vocal cords
‣ ‘p’, ’s’, ‘ch’
2. Manner - Nature of restriction of airflow in the vocal
tract
a) Stops
‣ Completely obstructed
b) Fricatives
‣ Partially Obstructed
c) Laterals
‣ Light obstruction
d) Affricates
‣ First blocked than allowed to sneak through
e) Nasals
‣ Blocked, at first, from going through the mouth, but
allowed to go through the nasal passage
3. ‣ Place - Place at which airflow is restricted
a) Labial (bilabial)
‣ At the lips
b) Alveolar
‣ At the ridge behind the teeth
c) Palatal
‣ Against the hard palate
d) Velar
‣ Against the velum (the soft palate)

Question 15

What is coarticulation?

Answer 15

one sound bleeds into the next (a restriction of language because we can’t move our tongues, jaws and vocal chords past a certain point)
- we often finish a word in the same mouth position that we started the word in

Question 16

What happens in normal speech, as opposed to an idealized speech pattern?

Answer 16

Movements of the articulators typically produce sounds
relevant to three phonemes simultaneously
‣ The end of one, the middle other, and the beginning
of a third
‣ This changes the frequency of the formants that
make up a particular phoneme

Question 17

Is there a regular signal in natural speech?

Answer 17

No
‣ The theoretically expected components
are often missing or distorted
‣ Because of coarticulation, no
correspondence between acoustic
properties and perception of speech
‣ We have a lack of invariants in an 
- we have to encode things like formants because those give us phenomes

Question 18

How can we get past the problem of coarticulation?

Answer 18

Using a global approach to speech recognition where the relationship between the parts are compared

Question 19

Are there specialized neural mechanisms that are responsible for speech recognition and processing?

Answer 19

Yes;
Broca’s Area: speech production
Wernike’s Area: speech comprehension

Question 20

What is the phonemic boundary?

Answer 20

the point at which our perception of one phoneme changes from one sound to another
- consonants show this categorical perception but not vowels

Question 21

What is the McGurk effect?

Answer 21

takes visual input and puts it against the audio input and the result is the midpoint between the two

Question 22

Is categorical perception of speech unique to humans?

Answer 22

No; for example, dogs have a specific brain region that encodes dog barking sounds
- dogs can learn human speech

Question 23

How do the formant and phoneme rules change?

Answer 23

Depending on what language you are learning

Question 24

What is phonemic restoration?

Answer 24

A kind of perceptual completion in which listeners seem to perceive obscured or missing speech sounds
- based on previous experience and is therefore a top-down information processing event

Question 25

What does the location of the fundamental frequency on the cochlea depict?

Answer 25

perception of pitch

Question 26

How is music simpler than human speech?

Answer 26

Because it combines different frequencies across the harmonic spectrum
- fundamental frequency must be present for our perception to figure out that specific sound

Question 27

What are semitones?

Answer 27

The 12 proportionally equivalent intervals between the
notes in an octave (C - C# - D - D# - E - F - F# - G - G#
- A - A# - B)

Question 28

What is tone height?

Answer 28

Notes separated by an octave are more
perceptually similar than separated by
another scale

Question 29

What is tone chroma?

Answer 29

Semitone intervals are perceptually
equivalent - same perceived difference
in pitch

Question 30

What are tonal superpositions?

Answer 30

two tones played together

Question 31

What is consonance?

Answer 31

Quality exhibited by a combination of tones that
sound pleasant
- notes that are derivatives of each other
- reinforce the response of the other on the basilar membrane

Question 32

What is dissonance?

Answer 32

Quality exhibited by a combination of tons that
sound unpleasant
- interfere with each other on the basilar membrane