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Flashcards in Problem 9 Deck (28)
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1

Acoustic signal

Refers to the patterns of pressure changes in the air

--> created by air that is pushed from the lungs past vocal cords and into the vocal tract

2

Articulators

Structures including the

a) tongue
b) lips
c) teeth
d) jaw
e) soft palate

--> movement of theses structures alters the shape of the vocal tract

3

Vowels

Vowels are produced by the vibration of the vocal cords

--> some vowels have more than one pronunciation
--> there are more vowel sounds than letters !

ex.: "e" sounds different in "head" and "heed"

4

Formants

Frequency peaks due to resonance of the vocal tract

--> our voice produces an infinite number of formants
--> formants 1+2 are responsible for vowel sounds
--> each vowel sound has a characteristic series of formants

5

Sound spectrogram

Indicates the pattern of frequencies and intensities over time that make up the acoustic signal

6

How are consonants produced ?

Consonants are produced by a constriction or closing of the vocal tract

7

Formant transitions

Refer tp rapid shifts in frequency preceding or following formants

--> associated with consonants

ex: "read"

8

Phoneme

Refers to the shortest segment of speech that, if changed, would change the meaning of a word

--> are defined in therms of the sounds that are used to create words in a specific language

9

Coarticulation

The fact that the pronunciation of a sound in a word is affected by the sounds before and after it

ex.: "boot" vs "bat"

--> even though "b" is the same in both words, one articulates each differently

10

Why is coarticulation an example for perceptual constancy ?

Because be perceive the sound of a phoneme as the same even though the acoustic signal is changed by coarticulation

11

Why might different speakers have different acoustic signals for the same phoneme or word ?

a) slow or fast speech

b) high or low pitched voice

c) sloppy pronunciation

--> all of these variabilities are reflected in spectrograms
--> listeners must transform this info into familiar words

12

Categorical perception

Occurs when stimuli that exist along a continuum are perceived as divided into discrete categories

13

Voice onset time
(VOT)

Refers to the time delay between when a sound begins and when the vocal cords begin vibrating

--> property that helps us divide phonemes into discrete categories

14

Phonetic boundary

The point along the continuum in which the perception of speech sound changes from one category to another.

--> ex.: change form "da" to "ta"

15

Why is phonetic boundary an example of perceptual constancy ?

Because all the stimuli on the same side of the phonetic boundary are perceived as the same category

--> this simplifies our perception of phonemes

16

Why is our speech perception "multimodal" ?

Because it can be influenced by information from a number of different senses

17

McGurk effect/
Audiovisual speech perception

Although auditory information is the major source of information for speech perception, visual information can also exert a strong influence on what we hear

18

Which cortical areas are activated when perceiving speech ?

Auditory cortex: lipreading

Superior temporal sulcus: Speech perception

19

Phonemic restoration effect

Under certain conditions, sounds actually missing from a speech signal can be restored by the brain and may appear to be heard

--> meaningfulness makes it easier to perceive words
--> knowledge of grammar enhances effect

20

Speech segmentation

Perception of individual words in a conversation

--> meaning + prior knowledge are responsible for organizing sounds

21

Transitional probabilities

Describe the chances that one sound will follow another sound

22

Statistical learning

The process of learning about transitional probabilities + about other characteristics of language

23

Indexical Characteristics

Taking in characteristics of the speakers voice

--> carries information about the speakers

a) gender
b) age
c) place of origin
d) emotional state
e) being sarcastic or serious

24

Aphasia

Inability (or impaired ability) to understand or produce speech, as a result of brain damage

25

Brocas aphasia

Labored + stilted speech
--> only able to speak in short sentences

BUT: still capable of comprehension

26

Wernickes aphasia

1. Extremely disorganized + meaningless speech

2. Difficulty understanding what others say

BUT: fluent speech

27

Motor theory of speech perception

1. Hearing a particular speech sound activates motor mechanisms controlling the movement of the articulators

2. Activation of these motor mechanisms activates additional mechanisms that enable us to perceive the sound

28

Dual streams model

We use the ventral + dorsal pathways to perceive sounds

ventral --> gives a sound a meaning
dorsal --> sounds into movement