Theories of phon acq

Linear theories

Notes

None fully account for dev of phonological system

Need to choose which theory fits

All quite interlinked

Elements may overlap

Dev. requires innate knowledge, capacity, influence of positive env factors

Assumption

Each discrete segment of string of sound elements consists of bundle of distinctive features

Common set of distinctive features attributable to all sound segments according to binary +/- system

All sound segments have equal value, all distinctive features are equal.

Phon rules, processes generate apply only to segmental, and to changes that occur in distinctive features

1. Behaviourist theory

States that

Impt bcos

Focus on observable behaviours, alter response accordingly eg. early vocalisations bcos they want food

Includes stimulus (env)-response (behaviours) paradigm

Emphasises role of reinforcement 1) Learner's vocalisations become self-reinforcing when they are like the adult's
2) Adult selectively reinforces sounds that resemble target lang eg. bʌ for banana- child knows they need to change response to get what they want.

Need to communicate is inherent in this theory-wish to have banana

Limitation: speech too complex to be achieved by reinforcement. eg. some chn give up when it's too much for them

Need to tell parents that they should give child opportunity to produce sound, X give banana until they say whole word. Child has to alter speech to get what he wants.

Emphasise on need to communicate. Reinforce this behaviour of alteration

*Positive reinforcement- motivate child, impt to give reinforcement to get another food production, motoric production, ling reinforcement

2. Structuralist, universal order theory

States that

Impt bcos

Universals exist in dev. of all lang eg. if a lang has back consonants, it must have front consonants ; oral vs. nasal

Principle of maximal contrast (to produce range of words we need) accounts for basic consonant, vowel structure of lang

suggest that there is same, innate order in stages of phonemic contrast

rate of progression thru stages can differ

seq of stages can differ, based on feature oppositions, contrasts

Limitations: acq order may differ

Educate parents that rates of progression can differ, although same, innate order, we are X working on sounds that have not dev for their age.

Biling: learning in diff orders --> Tx impacted

Recognising when child is doing his own thing, artefact of child's presentation

3. Distinctive feature theory

Impt bcos

States that

Underlying representation of phoneme is distinctive feature

Analysis based on features missing, not contrasted, eg. -voice, +voice, then contrasted in minimal pairs

Concept of markedness 1) unmarked-more natural, more common, more freq in most lang, established before marked sounds 2) marked sounds-less natural eg. voiceless obstruents /f/ more common than voiced obstruents /v/

Unds why sound is hard for child to produce

Limitations: does not account for omissions, cannot account for all phonetic features

+ve way of way they have, what they can do

Works when teasing apart atypical sound processes in child (use +/- distinctive features)

4. Generative phonology theory

States that

Impt bcos

Aims to establish mapping b/w implicit knowledge of sound system, explicit use of system

Concept of phonological rules describe 1) surface phon representation (what speaker says), 2) underlying phonological representation (phon rule can change what's inside, what comes out, context dependent), mental reps of words), 3) when surface form used

Processes subsumed under phon processes for SLPs

Limitation: Theory based on assumption that child's underlying representation is adult-like. But what about fis phenomenon: child X recognise that their own production is wrong. X practical, time consuming to write down

Useful for unusual processes eg. ICD of voiceless consonants only.

Child might not be aware of their underlying representation

Range of representation child might go thru from WRONG to CORRECT (recognise this as gradual impv)

5. Natural phonology theory (Most relevant to SLP)

States that

Children begin w set of innate, universal processes so that they can simplify production --> eliminate according to rules of that lang

Processes are thought to be phonetically motivated by physical properties of speech

Suppression of processes in response to listening to native speakers- change process to match adults

Some sounds more natural cf. others

Underlying representation--> Natural phon process--> Child's surface representation. So when you say 'bɒt' for /spɒt/, child recognises this is wrong



Innate system changes by 1) limitation-process applies to fewer sounds, fewer env 2) ordering-processes used in more organised way ʃ--> t --> d 3) elimination

Limitation: unusual processes not accounted for w/i this theory.

  1. Optimality theory

States that

Suggest that it is diff from other ling theories of acq which concentrate on mental representations, phon rules; this concentrates on constraints

Suggest input, output representations that may differ according to universal set of constraints

Output is the one that is most optimal depending on constraints eg. car may be /ta/ but not /bi/

Markedness constraints: output simplified by not using sounds which are marked

Faithfulness constraints: input, output should be the same, X have addition, deletion of features

Limitation: confusing b/w two diff constraint types

7. Gestural phonology theory

States that

Impt bcos

Most theories focus on phonemes but this one focuses on gestures, mvm of articulators

Gesture-abstract motor goal representing a point of constriction in vocal tract

Each gesture can be achieved in diff ways

Tell client that there are diff ways to produce a sound

Gestures are constant, context independent

Errors happen in 2 ways 1) shaping of gestures 2) type of articulatory mvm-ballistic mvm eg. plosives, nasals ; slow, constant velocity of mvms eg. glides; fine force mvms eg.fricative

Limitations: No linguistic consideration, X recognise phonological acq theory, X contrastive rules

Advantages

Disadvantages

Efficient approach for relational Ax

Efficient approach to Tx

Consideration of larger linguistic units?

Possibility of hierarchical interaction b/w segments, other ling units

Variation in description of processes for normal, disordered dev.

Non-linear theories

Advantages

Considers segments as governed by more complex ling dimensions

Linear representation of phonemes play a subordinate role

Complex ling dimensions eg. stress, intonation, metrical, rhythmical ling factors may control segmental conditions

Dynamic system of features: ranked one above the other eg. syllable structure could affect segmental lvl

Implications

Child may demonstrate deleting final consonant of each syllable in multisyllabic word, but no consonant deletion occurs in one-syllable words

What is it?

No. of syllables in word interacts w, affects segmental level. More syllables in word affects output

No. of syllables has priority

Children tend to delete segments in unstressed syllables

Defaults (easiest to say)

Coronal (blade, tip of tongue)

Eg. n,t,d,s,z,l,r,j,ʃ,ʒ,θ,ð,tʃ,dʒ

Sometimes /d/ can be default

Sometimes /l/ can be default, may serve general purpose of substitution for alternative groups of sounds