451 Models of Phonological Development

• 1) Account for common developmental patterns
• 2) Account for individual differences
• 3) Account for developmental change – Continuity
• 4) Relate to observable behaviors
• 5) Provide an index of severity
• 6) Aid in the development of treatment programs for children w/ phonological &articulation disorders

Behavioral

Structural

Natural

Generative

Cognitive and Psycholinguistic

Biological

Nonlinear

Proponents: Mowrer, Olmstead

Underlying premises:

• 1) Psychological Theory of Learning
• 2) Contingent Reinforcement / Classical Conditioning

Babbling is shaped via classical conditioning principles

Infant associates vocalizations of caretaker w/ ‘primary reinforcement’ of food and comfort

Caretaker vocalizations become a secondary reinforcement

Child’s vocalizations are also secondary reinforcement as they are similar to caretaker’s productions

Infant vocalizes- caretaker reinforces it- thus babbling is self-reinforcing


Speech sound repertoire is further refined as:

• 1) Caretaker reinforces selective sounds that resemble those used in adult language
• 2) Child is self-reinforced for producing sounds that match adult productions

Emphasizes ‘Continuity’ between babbling and early speech

1) Does not account for novel productions or new patterns

2) Little evidence to show that caretakers selectively ‘reward’ a child’s sound production in the pre-linguistic period

Proponent: Jakobson

Premises:

• 1) Structuralist Theory of Language
• 2) Universal & innate order of acquisition
• Hypothesized a ‘Discontinuity’ between babbling & speech, stating ‘babbling’ was completely random & unrelated to speech production
• Basic units are distinctive features

Distinctive features of sounds ‘unfold’ in a predictable order

Occur as child produces phonemic contrasts

• Child starts with maximally contrasting sounds:
• /p/ and /a/ (closed vs open), THEN
• /m/ and /p/ (oral vs nasal labials), THEN
• /n/ and /d/ (oral vs nasal alveolars)

Features needed to differentiate stops , nasals, bilabials, & alveolars occur earlier than those needed to differentiate fricatives, affricates, and liquids.

1) Existence of regularities in paralinguistic vocalizations, i.e. babbling, have been clearly documented

2) Correlations between babbling and adult-based 1st word shapes is clearly documented

3) No evidence that children ‘contrast’ sounds (phonemic opposition) at prelinguistic stage

4) Children are thought to target ‘whole word shapes’ rather than phonemes or segments

5) Fails to account for great variability observed in children’s early speech productions

Smith’s findings:

• 1) Found no evidence that a child had his own system
• 2) The postulated ‘child’s system’ seemed to have no bearing on child’s response to unfamiliar adult forms, on phonological treatment of new forms, or recognition of older forms under the influence of new patterns. 3) Thus, Smith postulated there are ‘universal tendencies’ that are innate or learned early

Background:

• A ‘natural’ phonological process is innate, acquired early, & easily used by the child.
• A ‘natural’ sound class or phonological property or rule is one that appears to be preferred by the child & is frequently used in their phonological system
• If the ‘natural’ process opposes a phonological property, some resistance may be expected.

Proponents: Stampe,Donegan & Stampe,Smith

Premises:

• 1) emphasizes universal & maturational aspects of phonological acquisition
• 2) Child is innately equipped with a universal set of phonological processes for production simplification
• 3) Child uses phonological operations or processes which change, delete, or simplify phonological units & simplify adult target
• 4) Child has innate ability to simplify phonemes they can’t produce
• 5) As child perceives phonemes & learns to produce them, they suppress the phonological process that was acting upon them
• 6) Child suppresses processes which do not occur in their native language EX: English vs German

Phonological processes reflect the natural limitations and capacities of human vocal production & perception


Stampe – 3 mechanisms that account for ongoing changes in child’s phonological system

• 1) limitation
• 2) ordering
• 3) suppression

1) Concept of ’universal phonological rules’ is controversial

2) Postulates accurate perception of speech production from earliest stages, .i.e. ability to perceive and store speech forms correctly - also controversial

3) Doesn’t account for individual variation/difference

4) Doesn’t account for difference in order of acquisition

5) Doesn’t address babbling

6) Doesn’t account for early correct productions which are then temporarily lost and later regained.