carol stoel -gammon barbara may bernhardt

NOVA Comprehensive Perspectives on Child Speech Development and Disorders

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Chapter 1Child Phonology, Phonological Theories, Clinical Phonology:

Reviewing the History of our Field

Carol Stoel-GammonBarbara May Bernhardt


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Introduction

• The purpose of this chapter– Recount the emergence and early period of the

study of child phonology – Review linguistic theories of phonological

development– Introduce clinical phonology


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Child Phonology

• A field in its infancy– Clinical phonology is a relatively young field (20th century)– Two strands evolved separately, then merged:

• Educators and psychologists, 1930s – 1950s– Group studies– Norms for age of acquisition for each phoneme– Templin’s (1957) summary chart of expected age of phoneme acquisition

• Individual researchers with training in linguistics, prior to 1960s– Diaries, case studies– Speech and language development– Attempted to test various linguistic theories– Humphreys (1880), Hills (1914), Waterson (1971), Smith (1973), Labov

and Labov (1978)


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Sidebar 1.1 Some Obsolete Terms Used to Describe Child

Speech and Children with Speech Disorders, 1930s to

1960s

Defective articulation

Idiots and imbeciles

Infantile linguistics

Mentally deficient children

Mongoloid speech

Speech defective child

Speech defects


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Contributions of the Stanford Group

• Charles Ferguson, head of Linguistics at Stanford University, played a key role in the emergence of the field of child language acquisition from a linguistically oriented perspective

• First course on language acquisition 1967• Stanford Child Language Research Forum• The field of child phonology is one of his legacies• Initial grant proposal in 1967 was the first of many to obtain funding• “Child Phonology Project”• Group members included Mary Louise Edwards, David Ingram, Marlys

Macken, Lise Menn, Marilyn Vihman, Carol Stoel-Gammon, and Barbara May Bernhardt

• Children from various linguistic backgrounds were studied including English, Spanish, Swedish, Japanese


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Major Issues in the Field of Child Phonology

Cognitive-linguistic vs. articulatory aspects• Learning in two domains:

– Awareness of sounds and sound patterns; develops long before speech emerges

– Actual productions of speech sounds– Unknown how these two processes interact in typical

development and influence various aspects of disordered speech• The search for universals, e.g., generally,

– Stops are acquired before fricatives– Singletons are acquired before clusters– Unaspirated stops are acquired before other types of stops– BUT: Children differ in how they go about acquiring the speech

sound system


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Cognitive-linguistic vs. articulatory aspects (ct’d)• The Nature of Underlying Representations (URs)

– A proposed mental “dictionary” with lexical, syntactic, semantic, acoustic, and articulatory information

– There is little agreement about the number and nature of URs in children (or even in adults) • Only one UR that is phonemic and abstract (Chomsky & Halle, 1968)• A single UR, based on the adult form, guides recognition and production in young children

(Smith, 1973)• Two separate URs, auditory vs. articulatory (discussed in Menn & Matthei, 1992; Beckman,

Munson, & Edwards, 2007; Munson, Edwards, & Beckman, in press)• Usage-based model where there is no fixed UR (Sosa & Bybee, 2008) – a single word may

have multiple representations• Consider this: Even very young children can detect a mispronounced word at an age where

their own productions differ from the adult form• Therefore, the question about URs and the relationship between perception/comprehension

and production remains open


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The Evolution of Research Methodology

Samples Data Analyses

Then(1930s – 1950s

Single child (longitudinal)

Small groups (cross-sectional)

Transcribed spontaneous speech

Transcribed elicited single-word productions

Focus on accuracyAge of acquisition of

individual phonemes

Now (since 1960s)

Wide variety of formats

Online repositories, e.g., Child Language Exchange System (CHILDES)

Transcribed speechDigital sound recordingsKinematic tracesPalatographyUltrasound

Error pattern analysisAcquisition by sound class


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Theories of Phonological Development: A Brief Overview

Requirements of a theory1. Must account for both child and adult forms; must

accommodate general patterns as well as variations among and within individual children

2. Must account for relationships between prelinguistic and linguistic development; perception and production; acquisition and input

3. Must account for phonetic and phonological learning4. Must be compatible with general theories of learning5. Like all theories, must make testable predictions


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Structural Theory

• Roman Jakobson (1941/1968)• Systematic description of the elements and structures of language

– All languages of the world have some of the same structural levels (sentences, phrases, words, syllables, sounds)

– Within each level, elements can be sorted into categories– The categories are binary, e.g., vowels can be open or closed, front or back– Claim: Children follow the structural principles and implicational

hierarchies in the phonemic inventories of adult languages, e.g., when velar stops are in error, they are produced as alveolar stops; when fricatives are in error, they are produced as stops

– As you will see, much of these predictions have merit– Structural linguistic theory, however, is now considered obsolete. The next

wave was generative grammar


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Rule- and Process-Based Theories• Premise: Children are born with a set of preferences that are

modified by exposure to the ambient language– Chomsky’s (1968) generative grammar

• Underlying forms -> surface forms• Children derive the underlying forms of language from being exposed to actual

examples• Underlying word form -> child’s actual production governed by a set of rules

– Stampe’s (1969) natural phonology• Child’s system is based on aerodynamics, motoric variables• To produce an adult target, the child suppresses, limits, or re-orders his/her

natural preferences• Example: V + Obstruent C + V: the C tends to be voiceless because the air

pressure required to produce it but tends to be voiced between two vowels. This conflict can be resolved by suppression of one process, limiting the process to certain environments, or rank-ordering the processes.

• Speech errors occur when the child’s processes are different from the adult form


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Nonlinear Theories

Figure 1.1 The word “snowman” from the word tier to the segmental tier

Note: F = foot, σ = syllable, O = onset, R = rime, RN = root node.


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Optimality Theory

• Prince and Smolensky (2004)– Constraint-based– Two competing sets of constraints:• “Faithfulness” constraints: Pronounce the word as

closely as possible to the adult form you hear• “Output” constraints: Go as easy as possible on your

articulatory system– As the child develops more sophisticated speech

output, the constraints get re-ranked until the faithfulness constraints have priority in all cases.


• OT assumes an inherent tension between producing linguistic forms that are easy (unmarked) versus linguistic forms that are true to the actual and sometimes marked (=complex) lexical forms

• It’s called Optimality Theory because the final form that emerges from the interaction with the two types of constraints are the “optimal” ones – with the least number of constraint violations

• All languages have – Unmarked forms (basic, preferred; “vanilla”), e.g.,

• Vowels: /a, e, i, o, u/ where front vowels are [- round]) • Syllables: CV

– Marked forms (exceptional, necessary to create contrast; “mango”), e.g.,• Vowels: /ø, y/) front rounded vowels [+ round]• Syllables: CVC, CCVCC


• Markedness is the foundation for OUTPUT CONSTRAINTS = MARKEDNESS CONSTRAINTS, e.g.,• Vowels must not be nasal• Syllables must not have codas• Syllables must have onsets• Obstruents must not be voiced in coda position

– The sometimes complex lexical form of a word is the foundation for INPUT CONSTRAINTS = FAITHFULNESS CONSTRAINTS, e.g.,• The output must preserve all segments present in the input• The output must preserve the linear order of segments in the input• Output segments must have counterparts in the input• Output and input segments must share values for [voice]


Candidates for input /lid/

*VOICED-CODA IDENT-IO(voice)

a. [lid] *!b. [lit]☞ *

Tableau for the German word /lit/ (“song”); plural = /lidəɐ/, so the underlying form is /lid/

* = constraint violation*! = fatal constraint violation

☞ = optimal candidate that violates the least constraintsIDENT-IO(voice): faithfulness constraint requiring that the input

matches the output with respect to voicingConstraints are ranked from left to rightAfter a fatal violation occurs in one column, the violations to its right

become less important and are shaded in grey


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Usage-Based Theory

• Kemmer and Barlow (2000)– There is no mental underlying representation of a

speech sound– Each time a word is said, learning occurs– The frequently occurring sounds and sound

sequences are acquired before the less frequently occurring ones.


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Biological Models

• Kent (1992)– Speech development follows biological

development– Motor control of the articulators (e.g., tongue)

increases with development and results in more precise and less variable sound productions


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Cognitive Theories (“Child Centered” Theories)

• Ferguson and Farwell (1975)– Arose from the realization that theories based on

adult speech were inadequate to describe child speech acquisition

– The child drives his/her own phonological development

– Children prefer to talk about things that are easier for them to pronounce (lexical selection)


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Appraising the Theories

• No one of the theories fulfills all “requirements of a theory”

• Each focuses on one aspect of speech development

• Each has merit in itself• Still lacking: a comprehensive theory or model

that integrates across the various domains involved in phonological acquisition


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Clinical Phonology

Introducing clinical phonology• Similar to child phonology, clinical phonology underwent

changes– Especially in English-speaking countries

• Clinical phonology followed the trends in child phonology– But usually with a lag time of several years

• Clinical phonology is based on the scientific method – Define the aims of assessment or treatment, choose methods,

observe the results, analyze and interpret the results


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• Clinical phonology is informed by many disciplines and technologies– Phonetics

• Transcription• Acoustic analysis• Articulatory analysis

– Tongue-palate contact patterns, movement patterns, nasalance, respiratory and vocal characteristics

– Psychology• Developmental theories• Information processing• Perception, memory, attention• Social interaction• Brain and behavior• Assessment tools• Treatment methods

– Other sciences• Biology• Neuroscience• Computer technology for data collection/interpretation


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The Clinical Enterprise

• The purpose of a clinical assessment – Compare the child to peers– Determine whether there are communication breakdowns in

daily life• Speech sample collection– Many different ways, depending on the child

• Standardized assessment• Play session with strategically selected objects• Use of technology (electropalatography, electroglottography,

ultrasound)• Use of computerized analysis programs (e.g., CAPES, PHON, PROPH)


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• Analysis and goal selection– Interpret the findings (nature of speech errors, comparison with age/sex

controls)– Determine whether or not the child qualifies for treatment

• Speech sample collection• Types of treatment reflect the influence of linguistic theories

– Structuralist theories: focus on single consonants (Van Riper, 1939, 1978)– Phonological process or rule-based theories: focus on patterns comparing

the child’s forms to adult targets– Nonlinear phonology: focus on the levels of impairment (e.g., word

structures, segmental features)– Optimality theory: focus on suppressing articulatory constraints

• Treatment program should fit the child’s profile


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Sidebar 1.2 Selected Computer Programs for Speech Analysis

CAPES ®, Computerized Articulation and Phonology Evaluation System

(Masterson & Bernhardt, 2001):

http://www.pearsonassessments.com/HAIWEB/Cultures/en-us/Produ

ctdetail.htm?Pid=0158123999&Mode=summary

LIPP, Logical International Phonetics Program (Oller & Delgado, 1999):

http://www.ihsys.com/site/LIPP.asp?tab=4

PHON (Rose & Hedlund, 2011): http://childes.psy.cmu.edu/phon/

PROPH, Profile in Phonology (Long, 2011):

www.computerizedprofiling.org

Phoneme Factory Phonology Screener (Wren, Hughes, & Roulstone,

2006):

http://www.gl-assessment.co.uk/health_and_psychology/resources/p

honeme_factory/phoneme_factory.asp

http://www.pearsonassessments.com/HAIWEB/Cultures/en-us/Productdetail.htm?Pid=0158123999&Mode=summary

http://www.pearsonassessments.com/HAIWEB/Cultures/en-us/Productdetail.htm?Pid=0158123999&Mode=summary

http://www.ihsys.com/site/LIPP.asp?tab=4

http://childes.psy.cmu.edu/phon/

http://www.computerizedprofiling.org/

http://www.gl-assessment.co.uk/health_and_psychology/resources/phoneme_factory/phoneme_factory.asp

http://www.gl-assessment.co.uk/health_and_psychology/resources/phoneme_factory/phoneme_factory.asp


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• Single sound in error– Often sufficient to analyze on segmental level– Can use tools (EPG, ultrasound) to determine tongue position

• Multiple sounds in error– Look for patterns

• Pattern-based treatment is more efficient than targeting individual phonemes– Consider word structures

• Assessment of related factors: Contextualizing the phonology– Hearing screen, play-based hearing assessment– Phonological awareness– Oral structures and functions– Effect of the disorder on social and physical aspects of daily life


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• Treatment across various paradigms– Focus on production (e.g., minimal word pairs)– Perceptual focus– Word-based focus (core vocabulary)– Morphosyntactic focus (sounds in word endings,

e.g., plurals, possessive, past tense)– Holistic language focusing on topic development


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Connections• This chapter opens the door to comprehensive perspectives of speech sound

development and disorders• It traced the methodological beginnings of child phonology and clinical

phonology• Chapter 2 describes tools for describing and measuring children’s speech

abilities • Whereas this chapter described some of the earliest insights about speech

development, the chapters in Section II summarize current knowledge about typical speech development in detail

• The chapters in Section III describe speech development in languages beyond English

• Whereas this chapter outlined some of the linguistic theories based on adult speech and their interactions with clinical phonology, the chapters in sections IV and V describe current applications in assessment and treatment


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Concluding Remarks

• Rapid changes in technology• Influences from information processing and

linguistic theory• Focus on languages other than English• The current textbook reflects these aspects

carol stoel -gammon barbara may bernhardt

Documents

child speech development

speech disorders

typical development

infancyclinical phonology

young field

various linguistic backgrounds

language developmentattempted

age of acquisition