2. phonological acquisition Flashcards
What are the five stages in pre-linguistic sound development?
- Reflexive vocalisations/ reflexive crying and vegetative sounds (birth - 2 months)
- Cooing and laughter (6 - 8 weeks)
- Vocal play (or ‘expansion stage’) (4 - 6 months)
- Babbling (6 months and older)
- Jargon stage (10 months+)
Explain the first stage in pre-linguistic sound development (reflexive vocalizations / reflexive crying and vegetative sounds)
What sounds/types of sounds are produced at each stage?
birth - 2 months
- Reflexive vocalisations: crying, fussing
- Vegetative sounds: coughing, burping, sneezing
- Can include (involuntary) vibration of vocal cords
- Can make some vowel-like sounds
- Restricted in range by immature vocal anatomy of infant: small oral cavity, and the position of the larynx
Explain the second stage in pre-linguistic sound development (cooing and laughter)
What sounds/types of sounds are produced at each stage?
6 - 8 weeks
- Rapid growth of the head and neck – more variety in sound production
- Cooing = comfort state vocalisations - indicate happiness/contentment/comfort
- Sounds at the back of the mouth: velars /k/, /g/ and back vowels (‘oohs’ and ‘aahs’)
- Vowels predominate, especially in early stages
- Becoming more diverse and longer
Explain the third stage pre-linguistic sound development (vocal play; or ‘expansion stage’)
What sounds/types of sounds are produced at each stage?
4 - 6 months
- Babies are testing their vocal apparatus
- Playing & experimenting - involving extremes of sounds (high, low, loud, quiet):
- e.g. yells, whispers, squeals, growls, friction noises
- series of raspberries (bilabial trills)
- sustained vowels
- Around 6 months there is an increase in phoneme repertoire: sounds at the front of the mouth /m/, /n/, /d/, /p/, /b/
- May stop producing back sounds
Explain the fourth stage pre-linguistic sound development (babbling)
What sounds/types of sounds are produced at each stage?
6 months and older
- Produces CV sequences that resemble
syllables, with adult-like rhythm - There are 2 stages:
- reduplicated babbling, where the child produces strings of identical syllables e.g.
[bebe]; - variegated (non-canonical) babbling [bedigu], where the child produces strings with varying vowels and consonants
- it usually develops several
weeks after reduplicated babbling, but can develop quickly
- it usually develops several
- reduplicated babbling, where the child produces strings of identical syllables e.g.
Explain the fifth stage pre-linguistic sound development (jargon stage)
What sounds/types of sounds are produced at each stage?
10 months+
- Strings of sounds and syllables uttered with a rich variety of stress/timing and intonation patterns
- Sounds like adult intonation
- This stage overlaps with meaningful speech
- Babies are starting to communicate
Which sounds are used in babbling?
- Early sounds to some extent reflect ambient language
- Sounds used in babbling increasingly reflect phonemes used in ambient language as first word stage is approached (babbling drift)
- A relatively small set of consonants accounts for the great majority of consonantal sounds produced in early speech (late babbling/early words):
- stops [p, b, t, d, k, g]
- nasals [m, n]
- glides [w, j]
- fricative [h]
Which consonants are most frequently found in the early speech (babbling/first words)?
- stops [p, b, t, d, k, g]
- nasals [m, n]
- glides [w, j]
- fricative [h]
What is the relationship between sounds of babbling and sounds in first words?
- Consonants favoured in babbling are more likely to be produced correctly in first words
- Frequencies of sounds used in late babbling and in first words are very similar
How is the vocal tract of an infant different from adult vocal tract?
- smaller vocal tract & different shape
- higher larynx
- tongue fills the entire mouth – limited movement
- relative positions of epiglottis and vocal cords closer than in adult
- angle between oral cavity and pharynx shallower
- shorter vocal tract (affects sounds newborns can make)
As an infant’s vocal tract develops, which changes in the vocal tract are related to the increasing repertoire of sounds the infant is able to produce?
- Larynx begins to lower from 4-6 months (continues until 3 years)
- Vocal tract lengthens (average 8 cm in infants; 17 cm in adults)
- Angle between oral cavity and pharynx becomes more acute
- All changes leaves more space for tongue movement and alter the resonant qualities of the vocal tract
→ Permit a wider range of vowels
- Initially ribs are perpendicular to spine. From 3 months ribs start to angle down and out:
- better control of muscles
- enhanced control of air pressure
- periods of sustained or controlled phonation, necessary for speech
- Plus maturation of the central nervous system
- Greater motor control over articulators develops
Explain the syllable structure of early words and how it changes as a child gets older.
- Early words have simple structure
- Single syllable (CV) or reduplicated (CVCV: /dædæ/) though can say other more complex words, e.g. moon
- More complex forms such as CVCC and initial clusters later (after 24 months)
- And structures such as CCCVC not until > 3 years
But sound inventory is still limited /m/ /n/ /b/ invariably present but other sounds are typically later acquired: e.g. /ð/, /r/, /l/ etc.
Explain the 2 main types of phonological processes.
- Structural processes: whole word processes [changes structure of the target word]
- affect phonotactic structure of the word.
- usual in younger children (until 3-4 years)
- Systemic processes: segment substitution processes
- can persist longer (until 6 years)
Note: More than one process can be used in a word
Which processes are structural?
- weak syllable deletion
- reduplication
- final consonant deletion consonant
- cluster reduction
Explain weak syllable deletion (structural) and give 2 examples for each process
- omission of an unstressed syllable in the target word
- until about 4 years
Examples:
- potato /pəˈteɪtəʊ/→ tato [ˈteɪtəʊ]
- banana /bəˈnɑːnə/→ nana [ˈnɑːnə]
