3Behaviorist Model - Traditional Role of contingent reinforcement (environment) in speech acquisitionChild’s babbling shaped through operant principles – SkinnerChild associate vocalizations of caretaker withPrimary reinforcement such as food and comfortSecondary reinforcement is adult’s vocalizationCaretaker continues to reinforceThere is self-reinforcement
4Generative Phonology Model – Linguistic Models Innateness and universality – ChomskyPhonological rules map representations from deep to surface structures*Phonological rules are dependent on information from other linguistic levels.Distinctive featuresChild looks at the adult model and rewrites it into his modelDifferent way of organizing from adultUniversal tendencies innate or learned very earlyChild can process and it is in their production that there are problems
5Natural Phonology Model – Linguistic Model – Stampe Natural processes (patterns) are preferred or used.Those Universal across languagesThose frequently used by young childrenEmphasized universal and maturational aspect of phonological acquisitionChild comes innately with a natural set of phonological processes that reflect the natural limitations and capacities of human vocal production and perception. (operations to delete or change phonological units)
6Natural Phonology Model – Linguistic Model – Stampe Child’s task is to suppress those processes which do not occur in the particular adult language to which he is exposed.Child can process (can represent at the deep level the adult sound), it is in the production that there are problems
7Non-linear Phonology Model – Linguistic Model - Goldsmith Refers to a collection of theories that focus on the hierarchical nature of the relationships between phonological unitsProduction of speech involves more than just the production of phonemes, other elements influenceTwo main tiers – prosodic (word, foot, syllable, onset-rime, skeletal-word shape) and segmental (speech sounds and features)
8Optimality Theory – Linguistic Model – Prince and Smolensky Basic units are constraintsMarkedness constraints – limits what is permissible in a language, sounds that are difficult to produce or perceive are markedFaithulness constraints – features to be preserved.
9Sonority Hypothesis – Linguistic Model – Refers to the relative loudness of a sound relative to other sounds with same pitch, stress, and length.Voicing is importantSounds are given a numerical value to represent degree of sonority.Sounds with low sonority value are found at the syllable margina and sounds wit high sonority values are located toward the center.
10Psycholinguistic Models Explains children’s phonology by looking at perception, storage, planning and production in real timeDescribes underlying representations of words and their productionThey are interested in what happens between input and output. In between is a “black box” containing underlying representations or phonological information stored in the brain about words known and used (lexicon).Two lexicon model: one that holds words that are adult like perceptual representations, and a second lexicon which contains words that have already been transformed.
12Structuralists - Jakobson Phonological development follows a universal and innate order of acquisitionDistinctive features are arranged in a hierarchyDistinctive features unfold in a predictable order as the child produces phonemic contrasts embodying them.Child continues to learn new feature contrastsBabbling has nothing to do with the development of the sound system
13Prosodic Model - Waterson Focus on the word as the basic unitEarly words are schemas/templates that share features of adult forms (intonation pattern, syllable structure, presence of fricatives or voicing.Child’s perception and production of adult features is imperfect and must undergo development and change
14Cognitive Model Problem solving model Child encounters challenges Individual strategies dependent on natural predispositions and external factorsDifferent children begin mastering different articulatory patterns by attempting to produce different adult words
15Biological model - Locke Innate perceptual biases and dispositions to certain motor actionBabbling is phonetic repertoire is universal, constrained by physical structure and size of mouth, articulators, etc.Language environment starts to influence as of first wordsDepends on storage and retrieval of some relatively stable perceived forms of languageDevelopmental mechanismsMaintenance (of babbling patterns found in adult languageLearning (of non babbling patterns not found in adult languageLoss (patterns not found in adult)
16Self-Organizing Model - Lindblom Converges biological and linguistic modelsPhonetic forms in all languages have evolved to meet the complementary needs of the two participants in vocal communicationListenerSpeaker
17Self-Organizing Model -Performance constraints Needs of the listener are met – Ex. when a language uses vowels that are maximally distant from one another and easy to discriminateNeeds of speaker are met – needs of speaker are met when language uses consonant-vowel sequences which require little tongue movement and are easy to articulateCompromise between these two sets of performance constraints leads tophonetic universals or core segments – used in all languagesandexotic segments which occur only in languages with large phonetic inventories
18Self-Organizing Model – Performance Constraints A small set of articulatory gestures are used over and over in different combinations to produce word patterns or syllablesChildren use a small number of articulatory gestures which relate to core segments over and over again in different word patterns.This use will lead to the emergence of a network of phonologically contrastive segments (individual sounds emerging from the above syllables) – self-segmentation
21Problems faced by infants Segmentation ProblemPerceptual Constancy Problem
22Segmentation Problem English vowel lengthening is related to Syllable stressVoicing differencesWord boundariesClause boundariesWhat are the correct cues for segmenting words????
23Children must learn the segmentation problems with information processing and memory resources less than that of adults.Adults can process speech at 30 phonemes per second.Speakers are accessing meaning from the sound patters of words, working out the syntactic and semantic organization of utterances. This is done under a wide variety of distractions.One must learn routines for efficiency (learning more vocabulary, etc)
24Abilities Needed to Master Language Deal with speech variabilityVocal tract differencesAcoustic characteristic of word differ by speaker = perceptual constancy problemDifferences within a particular speakerChanges in production because of phonetic contexts
25Children must learn which phones serve as elementary sound units for forming words in their language.
26Learning words and building a lexicon Ability to segment fluent speech necessaryAspect of learning involves storing some information about the sound pattern of the word that allows its meaning to be accessed. It must sufficient to distinguish one word from another allowing variability.
27Some Suggested Strategies Grouping of utterances into clauses and phrases.Acoustic markings in speech directed to infantsUnstress and omit function words
29Categorical Perception Acoustic cues relevant to speech soundsVoicingAspirationPlace of articulation
30Solving the Segmentation Problem Phonetic predispositionAttunement to abrupt discontinuities
31Vocal and Articulatory Control Needed Before Learning Speech (Oller, 1976) During first year phonological development helps children attain the following competencies.
32Vocal and Articulatory Control Needed Before Learning Speech (Oller, 1976) Control of phonation or voice and the vocal mechanism.turn voicing on and off at will.Control of extremes and variations in pitch.first learn to make the distinctions between very high sounds and very low sounds.then learn to make finer pitch variations, which are necessary for intonation patterns.
33Vocal and Articulatory Control Needed Before Learning Speech (Oller, 1976) Control of extremes and variations in volumeGain voluntary control over extremes in volumeHelps between yelling and speaking softlyHelps distinguish fine variations for word and sentence stressHelps adjust volume to different listeners and speaking situations
34Vocal and Articulatory Control Needed Before Learning Speech (Oller, 1976) Control of resonanceFull use of resonant qualities not in their earliest utterancesThen they learn resonance for appropriate voice quality required for different speech needsControl of timing aspects of alternating resonance and constrictionsOpen and closed positions of the vocal tract develop into consonants and vowelsThey must become very rapid
37Sequence of Speech sound Acquisition – Bleile Phase 1: Laying the foundations for speech (birth to 1 year)Phase 2: Transitioning from words to speech 9 1 to 2 years)Phase 3: The growth of the inventory (2 to 5 years)Phase 4: Mastery of speech and literacy (5+ years)
38Vowel productionDuring the first year, vowel production dominates, maybe the lax vowels /,,,,/, front-low and mid central
39From word to segmentIt has been suggested that the earliest units the child targets for production are whole-word patterns rather than segments or even syllablesChildren try to produce whole wordsProsody matches that of whole wordsSome words or parts of words occur in advanced formsSome reorganization of sound patterns of words that are produced in advanced forms, and then are changed to the child’s overall patternsProgressive idiomsApparent regressionCreative strategiesPhonological selectivity or avoidance patternsProgressive idioms – word that is produced with phonetic accuracy and is different from the other words produced by the childSelectivity or avoidance patterns – children select which adult patterns they attempt, selection is based on phonological characteristics1. Apparent regression – a step backward for an individual lexical form in the service of greater progress or coherence for the child’s individual system as a whole2. creative strategies – learn one pattern based possibly on prosodic patterns (to maintain number of syllables) of adults and attach to simple forms.3.
40Components of typical speech acquisition Intelligibility - “Single most practical measurement of oral communication competence”Comparison of speech sounds with adult targetAcquired sounds: consonants, consonant clusters, vowelsPercent correct (PCC)Phonological patterns/processesAbilities of the child (without comparison to adults)Phonetic inventories: consonants, consonant clusters, vowelsSyllable structureProsodyMetalinguistic/phonological awareness skills
41Research and development Method of speech samplingDiary StudiesLarge-Group Cross Sectional StudiesCombined Data-Collection ProceduresIssuesSocioeconomic differencesNumber of subjects being studiedDefining masteryMastery of ProductionThe age at which particular phoneme is produced with some degree of accuracy ( %)Customary ProductionAge at which a particular phoneme is produced with greater than 50 % accuracy, in at least two word positions.