7: Auditory Perception and language development

Question 1

how do we study auditory perception

Answer 1

• conditioned head turn paradigm

- central fixation preference procedure

Question 2

conditioned head turn paradigm

Answer 2

-used to test whether infants discriminate two sound categories (“ba” and “da”)

-Conditioning (training) phase:
Start with sounds the infant can definitely discriminate
Infants trained to turn head to side when sound changes

2. Test Phase: Once infants conditioned to turn head when hear sound change, test infants on sounds of interest (e.g., language sounds ba vs. da)
   - infants who perceive sound change = turn head
   - infants who CANNOT perceive sound change = dont turn head

Question 3

central fixation preference procedure

Answer 3

• Infants integrate auditory and visual stimuli
• Infants look at visual stimulus in front of them (e.g., moving shapes)
• While infants looking at screen, auditory stimuli are playing
• Infants are habituated to the auditory stimuli (e.g., “ba”), and look away from the screen
• after habituation, play a new sound “da”
• if infants hear difference, they will renew interest in the visual stimulus

Question 4

changes in Phoneme perception

Answer 4

• Adults can only discriminate the phonetic contrasts of their native language.
• adult Japanese speakers can’t discriminate /l/ and /r/ phonemes in the English language
• adult English speakers can’t discriminate a Hindi distinction: the dental /d/ vs. the retroflex /d/

Human infants are born being able to discriminate all phonetic contrasts (from all human languages), even ones which their (native) language does not make.

Question 5

perceptual narrowing

Answer 5

-

Question 6

werker

Answer 6

• Infants quickly lose the ability to distinguish between sounds they haven’t experienced
• hindi

Question 7

Kuhl Tsao & Liu

Answer 7

• Infants are exposed to the sounds of their native language
• sound units (phonemes) that make up one language can be different from the sounds that makes up other languages
• In a Mandarin-speaking environment, infants’ ability to perceptually discriminate /r/ from /l/ diminishes between 6 and 12 months (perceptual narrowing)
• If these infants are exposed to repeated interactions with an English speaker prior to 12 months, the ability to perceptually discriminate /r/ from /l/ is preserved
• Similar exposure to voice-recordings of English speaker do not yield the same preservation in perceptual discrimination

Question 8

auditory perception and language

Answer 8

• The ability to perceive differences in the small sound units of speech lays a foundation for learning to produce and comprehend language
• The sound units (phonemes) we experience most frequently (i.e., from our native language) determine which languages we can speak and comprehend
• perception of small units of speech —-> comprehension & production of language

Question 9

saffran, Aslin, & Newport

Answer 9

• Play infants a constant stream of sounds, with no auditory cues for how the sounds should be parsed (e.g., no breaks in the sounds—just constant stream of speech
• The ONLY thing that is a cue for parsing the sound stream into words is the statistical regularity of syllable co-occurrence
• Some sound combinations occur with much higher probability than others!

Question 10

Saffran, Aslin & Newport study

Answer 10

-Infants habituated to acoustic stream

-Then infants hear words (high probability combinations)
moku, gapi

• Or infants hear part-words (low probability combinations
• babies are habituated to high probability combos
• babies look to low probability combos

Question 11

statistical word segmentation

Answer 11

: syllables that co-occur consistently tend to form words

Question 12

acoustic variation and statistical word segmentation

Answer 12

Requires recognizing repetitions of syllables in consistent vs. inconsistent pairings, across different pitches, voices, speaking rates, emotional tones