The inference of speech perception in the phonologically disordered child. Part II: Some clinically novel procedures. Their use, some findings

The Relationship Between Speech Perception, Speech Production, and Vocabulary Abilities in Children: Insights From By-Group and Continuous Analyses

PURPOSE

The purpose of this study was to explore the relationship between speech perception, speech production, and vocabulary abilities in children with and without speech sound disorders (SSDs), analyzing the data both by group and continuously.

METHOD

Sixty-one Australian English-speaking children aged 48-69 months participated in this study. Children's speech production abilities ranged along the continuum from SSDs through to typical speech. Their vocabulary abilities ranged along the continuum from typical to above average ("lexically precocious"). Children completed routine speech and language assessments in addition to an experimental Australian English lexical and phonetic judgment task.

RESULTS

When analyzing data by group, there was no significant difference between the speech perception ability of children with SSDs and that of children without SSDs. Children with above-average vocabularies had significantly better speech perception ability than children with average vocabularies. When analyzing data continuously, speech production and vocabulary were both significant positive predictors of variance in speech perception ability, both individually in simple linear regression and when combined in multiple linear regression. There was also a significant positive correlation between perception and production of two of the four target phonemes tested (i.e., /k/ and /ʃ/) among children in the SSD group.

CONCLUSIONS

Results from this study provide further insight into the complex relationship between speech perception, speech production, and vocabulary abilities in children. While there is a clinical and important need for categorical distinctions between SSDs and typically developing speech, findings further highlight the value of investigating speech production and vocabulary abilities continuously and categorically. By capturing the heterogeneity among children's speech production and vocabulary abilities, we can advance our understanding of SSDs in children.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.22229674.

Speech Perception Variability in Childhood Apraxia of Speech: Implications for Assessment and Intervention

PURPOSE

Beyond hallmark production deficits characterizing childhood apraxia of speech (CAS), largely attributed to disruption(s) in speech motor planning, children with CAS often present with co-occurring speech perception and language difficulties. Thus, careful consideration of the potential for speech perception difficulties to have cascading downstream effects on intervention responsiveness and real-life functioning for some children with CAS is highly important. The purpose of this tutorial was to consider the impact of speech perception abilities in children with CAS, which carries implications for caring for the needs of the whole child.

METHOD

This tutorial summarizes the current literature on speech perception and how it relates to speech production, language, and reading abilities for children with CAS. We include case illustrations that are adapted from real clinical scenarios illustrating how speech perception difficulties may impact some children with CAS and provide recommendations for incorporating speech perception into assessment and intervention practices.

RESULTS

Although speech perception difficulties do not seem to be a core deficit of CAS, they are strongly linked to language difficulties, which are highly prevalent among children with CAS. Speech perception and language difficulties are also associated with reading difficulties and risk for lower academic achievement.

CONCLUSIONS

Children with CAS who have co-occurring language difficulties likely also demonstrate speech perception deficits, which puts them at heightened risk for reading difficulties and struggles with academic achievement. Comprehensive assessment of children with CAS should address speech perception and production, language, and reading abilities, which carries important implications for multifaceted approaches to intervention.

Speech production and speech perception in children with speech sound disorder

The goal of the present study was to investigate the relationship between speech production (SP) and speech perception in children with Speech Sound Disorder (SSD) from both typical speech production (TSP) and child's own atypical speech production (ASP). Ten children with SSD were evaluated by a speech production task (naming test) and two speech perception tasks (phonological contrast identification) using the PERCEFAL instrument. In the identification task, the acoustic stimulus, from typical and child's own atypical speech productions, was presented to each child, and they needed to choose the corresponding stimulus between two pictures displayed on the computer screen. The percentages of errors on speech production (SP) task, on the identification task from TSP and ASP were calculated for each child. ANOVA showed a significant difference between speech production and speech perception. Post hoc analysis demonstrated a greater mean of errors in the ASP compared to the mean of errors in the TSP and SP performances. Only SP and ASP performances presented a significant correlation (r = 0.65). Errors involving manner and manner+place were most recurring in SP. TSP seems to precede SP; that is, children with SSD perceive more speech from typical production than they are able to produce. The significant correlation between ASP and SP suggests that the evaluation of these skills accesses the children's equivalent underlying phonological representation. A more accurate production, such as typical production, may have cues that help children with SSD to identify phonological contrasts, even if their underlying representations are overly broad or not established.

Speech Perception Skills of Children With Speech Sound Disorders: A Systematic Review and Meta-Analysis

Purpose The aim of this study was to conduct a systematic review and meta-analysis to investigate whether preschool- and early school-age children with speech sound disorders (SSDs) have difficulties with speech perception. Method Systematic searching of 8 electronic databases identified 73 eligible studies across 71 articles examining the speech perception skills of children with SSDs. The findings and methodological characteristics of each study were reviewed, and the reporting of methodological information in each article was rated. A meta-analysis was conducted with studies that used the most common type of speech perception assessment task-lexical and/or phonetic judgment tasks. Results Across 60 of 73 studies, some or all children with SSDs were reported to have difficulties with speech perception. The meta-analysis showed a significant difference between children with SSDs and children with typically developing speech on lexical and/or phonetic judgment tasks. Conclusion Results from the meta-analysis demonstrate that children with SSDs have difficulties with speech perception. This appears to be the case for some but not all children with SSDs. The findings from this systematic review and meta-analysis also provide insight into the complex range of methodological issues involved in the study of speech perception in children with SSDs and the need for further research. Supplemental Material https://doi.org/10.23641/asha.9808361.

Implementing Evidence-Based Practice: Selecting Treatment Words to Boost Phonological Learning

Purpose

Word selection has typically been thought of as an inactive ingredient in phonological treatment, but emerging evidence suggests that word selection is an active ingredient that can impact phonological learning. The goals of this tutorial are to (a) review the emerging single-subject evidence on the influence of word characteristics on phonological learning in clinical treatment, (b) outline hypotheses regarding the mechanism of action of word characteristics, and (c) provide resources to support clinicians incorporating word selection as an active ingredient in their approach to phonological treatment.

Method

Research demonstrating the influence of the word frequency, neighborhood density, age of acquisition, and lexicality of treatment stimuli on phonological learning is summarized. The mechanism of action for each characteristic is hypothesized. Methods from the research studies are used to create a free set of evidence-based treatment materials targeting most of the mid-8 and late-8 consonants.

Results

Clinicians have numerous evidence-based options to consider when selecting stimuli for phonological treatment including (a) high-frequency and high-density words, (b) low-frequency and high-density words, (c) high-frequency and mixed-density words, (d) low-frequency and late-acquired words, and (e) nonwords.

Conclusion

Incorporating word characteristics into phonological treatment may boost phonological learning.

KU ScholarWorks Supplemental Material

http://hdl.handle.net/1808/24768

The speech perception skills of children with and without speech sound disorder

PURPOSE

To investigate whether Australian-English speaking children with and without speech sound disorder (SSD) differ in their overall speech perception accuracy. Additionally, to investigate differences in the perception of specific phonemes and the association between speech perception and speech production skills.

METHOD

Twenty-five Australian-English speaking children aged 48-60 months participated in this study. The SSD group included 12 children and the typically developing (TD) group included 13 children. Children completed routine speech and language assessments in addition to an experimental Australian-English lexical and phonetic judgement task based on Rvachew's Speech Assessment and Interactive Learning System (SAILS) program (Rvachew, 2009). This task included eight words across four word-initial phonemes-/k, ɹ, ʃ, s/.

RESULTS

Children with SSD showed significantly poorer perceptual accuracy on the lexical and phonetic judgement task compared with TD peers. The phonemes /ɹ/ and /s/ were most frequently perceived in error across both groups. Additionally, the phoneme /ɹ/ was most commonly produced in error. There was also a positive correlation between overall speech perception and speech production scores.

CONCLUSIONS

Children with SSD perceived speech less accurately than their typically developing peers. The findings suggest that an Australian-English variation of a lexical and phonetic judgement task similar to the SAILS program is promising and worthy of a larger scale study.

Perceptual discrimination across contexts and contrasts in preschool-aged children

This paper investigates a proposed phonetically-based account of developmental phonological patterns that lack counterparts in adult typology. Adult listeners perceive some phonemic contrasts more accurately than others, and these differences in perceptual recoverability are posited to represent one influence on phonological typology. One hypothesis suggests that children and adults could differ in their patterns of relative perceptual sensitivity, and these differences could form the basis for some child-specific phonological patterns in production. However, there has been a lack of empirical evidence to support this claim. This study used a nonword discrimination task to investigate differences in perceptual recoverability across contrasts and contexts in typically-developing preschool children. Participants heard nonwords that were identical or differed by a single segment in initial or final position. Results revealed general agreement between child and adult listeners in the relative discriminability of different featural contrasts. For certain contrasts, discrimination accuracy was significantly greater in initial than final position, mirroring an asymmetry seen in adults. Overall, these results suggest that perceptual discrimination in preschool-aged children is broadly congruent with patterns of relative sensitivity observed in adult listeners. These findings suggest that factors other than perceptual recoverability should be explored to account for child-specific phonological patterns.

Bidirectional perception-production relations in phonological development: evidence from positional neutralization

Many children who neutralize phonemic contrasts in production exhibit diminished perception of the same contrasts. It is usually difficult to determine whether the perception deficit caused the production error, or vice versa; however, the direction of causation has implications for treatment planning. This study examines perception-production relationships in the phenomenon of neutralization in strong position, where children neutralize only in perceptually salient contexts. To test a hypothesis that this phenomenon arises from a child-specific pattern of perceptual sensitivity, a non-word discrimination task was administered to a 4-year-old boy with neutralization in strong position in production. Contrary to the perceptual hypothesis, his discrimination accuracy was greatest for contrasts in initial/strong position, where his production errors occurred. Independent of position, however, his perception of a phonemic contrast he neutralized was decreased relative to other contrasts. This case is argued to constitute evidence that a primary production deficit can cause decreased perceptual ability.

The Role of the Speech-Language Pathologist in Identifying and Treating Children With Auditory Processing Disorder

Purpose

A summary of issues regarding auditory processing disorder (APD) is presented, including some of the remaining questions and challenges raised by the articles included in the clinical forum.

Method

Evolution of APD as a diagnostic entity within audiology and speech-language pathology is reviewed. A summary of treatment efficacy results and issues is provided, as well as the continuing dilemma for speech-language pathologists (SLPs) charged with providing treatment for referred APD clients.

Conclusion

The role of the SLP in diagnosing and treating APD remains under discussion, despite lack of efficacy data supporting auditory intervention and questions regarding the clinical relevance and validity of APD.

What factors place children with speech sound disorders at risk for reading problems?

PURPOSE

To identify weaknesses in print awareness and phonological processing that place children with speech sound disorders (SSDs) at increased risk for reading difficulties.

METHOD

Language, literacy, and phonological skills of 3 groups of preschool-age children were compared: a group of 68 children with SSDs, a group of 68 peers with normal speech matched on receptive vocabulary, and a group of 68 peers with normal speech and language.

RESULTS

The SSD group demonstrated impairments in expressive phonological awareness (ts = 3.45 to 8.17, ps < .001, effect size [ES] = 0.51 to 1.04), receptive phonological awareness (zs = 2.26 to 5.21, ps ≤ .02, ES = 0.39 to 0.79), accessing phonological representations (zs = 3.34 to 5.83, ps < .001, ES = 0.59 to 0.91), quality of phonological representations (zs = 2.35 to 13.11, ps ≤ .02, ES = 0.44 to 1.56), and word reading (ts = 2.48 to 4.42, ps ≤ .01, ES = 0.22 to 0.54). Analyses of covariance found that lower performances of the SSD group on tests of phonological awareness and word reading could be explained by their weaknesses in quality and accessibility of phonological representations.

CONCLUSIONS

The present study makes a significant theoretical contribution to the literature as the first study, to our knowledge, that has tested the hypothesis that weaknesses in representation-related phonological processing may underlie the difficulties in phonological awareness and reading that are demonstrated by children with SSDs.

Assessing speech perception in young children and relationships with language skills

Few materials are available to assess speech perceptual skills in young children without hearing impairments. However, children with a range of developmental conditions are at risk of speech discrimination deficits. Tasks that reliably assess speech perception skills are thus necessary for research and clinical practice. The development and application of two speech perception tests are described. Data were collected from 105 children, aged 4-5 years, attending mainstream schools, on two tasks, mispronunciation detection and non-word XAB, in quiet and in a background of multi-talker babble. Children's receptive language skills were also measured. Performance on mispronunciation detection was significantly better than on the XAB non-word task, and significantly better in quiet than in babble. Performance significantly improved with age, and speech discrimination was significantly related to receptive language abilities. Scores obtained in quiet and in babble were highly correlated and findings suggest there may be no advantage to testing in noise, except to avoid ceiling effects on performance. These tasks prove useful in the assessment of young children who may have speech discrimination deficits.

Evaluation of a novel technique for assessing speech discrimination in children

Methods used to assess children's speech perception and recognition in the clinical setting are out of step with current methods used to investigate these experimentally. Traditional methods of assessing speech discrimination, such as picture pointing, yield accuracy scores which may fail to detect subtle perceptual difficulties. This paper will report a novel method of assessing speech input processing that uses measurement of children's eye movements to provide information on speed and confidence as well as accuracy in discriminating phonological contrasts. Participants were typically developing children aged 2-7 years. Pairs of pictures representing auditory minimal pairs which varied in type and degree of phonological contrast were presented on a computer screen while the child heard a word matching one of these pictures. The child's eye movements in response to these stimuli were videorecorded for subsequent analysis of duration and direction of gaze. The effects of age and stimulus type on eye gaze were examined. The results were compared with those of a traditional picture pointing task using the same stimuli. The informativeness of the novel technique is evaluated on the basis of the findings.

Testing the concurrent and predictive relations among articulation accuracy, speech perception, and phoneme awareness

The relations among articulation accuracy, speech perception, and phoneme awareness were examined in a sample of 97 typically developing children ages 48 to 66 months. Of these 97 children, 46 were assessed twice at ages 4 and 5 years. Children completed two tasks for each of the three skills, assessing these abilities for the target phoneme /r/ and the control phoneme /m/ in the word-initial position. Concurrent analyses revealed that phoneme-specific relations existed among articulation, awareness, and perception. Articulation accuracy of /r/ predicted speech perception and phoneme awareness for /r/ after controlling for age, vocabulary, letter-word knowledge, and speech perception or phoneme awareness for the control phoneme /m/. The longitudinal analyses confirmed the pattern of relations. The findings are consistent with a model whereby children's articulation accuracy affects preexisting differences in phonological representations and, consequently, affects how children perceive, discriminate, and manipulate speech sounds.

The emerging lexicon of children with phonological delays: phonotactic constraints and probability in acquisition

The effects of phonotactic constraints (i.e., the status of a sound as correctly or incorrectly articulated) and phonotactic probability (i.e., the likelihood of a sound sequence) on lexical acquisition have been investigated independently. This study investigated the interactive influence of phonotactic constraints and phonotactic probability on lexical acquisition in 3 groups of children: children with functional phonological delays (PD), phonology-matched, younger, typically developing children (PM), and age-/vocabulary-matched typically developing peers (AVM). Sixty-eight children participated in a multitrial word-learning task involving nonwords varying in phonotactic constraints (IN vs. OUT) and phonotactic probability (common vs. rare). Correct and error responses were analyzed. Results indicated that OUT sound sequences were learned more rapidly than IN sound sequences. This suggests that OUT sounds may be salient because they represent only a small subset of the child's sound system. The effect of phonotactic probability varied across groups: Children with PD showed a common sound sequence disadvantage, younger PM children showed a common sound sequence advantage, and AVM children showed no effect. Moreover, error analyses indicated that children with PD had particular difficulty creating lexical representations and associations between lexical and semantic representations when learning common sound sequences. Children with PD may rely more heavily on lexical representations to learn new words or may have difficulty learning common sound sequences because of the high degree of similarity between these sequences and other known words. Finally, the effect of phonotactic probability was consistent across IN and OUT sound sequences, suggesting that the lexical representation of both correctly articulated and misarticulated words is based on the adult-target pronunciation.

The development of early literacy skills among children with speech difficulties: a test of the "critical age hypothesis"

This article presents a longitudinal study of the early literacy development of 47 children with speech difficulties from ages 4 to 7 years. Of these children, 19 with specific speech difficulties were compared with 19 children with speech and language difficulties and 19 normally developing controls. The risk of literacy difficulties was greater in the group with speech and language difficulties, and these children displayed deficits in phoneme awareness at 6 years. In contrast, the literacy development of children with isolated speech problems was not significantly different from that of controls. A path analysis relating early speech, language, and literacy skills indicated that preschool language ability was a unique predictor of phoneme awareness at 5;8 (years; months), which, together with early reading skill, predicted literacy outcome at 6;9. Once the effects of phoneme awareness were controlled, neither speech perception nor speech production processes predicted variation in literacy skills. However, it is noteworthy that children with persisting speech difficulties at 6;9 were particularly vulnerable to deficits in reading-related processes.

The importance of sound identification training in phonological intervention

Little is known about the relevance of sound identification training in phonological intervention. Some treatment approaches incorporate sound identification training; others do not. The purpose of the present study was to compare articulatory improvement following treatment with and without sound identification training. Nine preschool children with severe phonological disorders were randomly assigned to 2 groups for the treatment of stimulable sound errors: (a) mixed training with concurrent production and sound identification training and (b) production-only training. Articulatory improvement was evaluated as a function of treatment type and pretraining sound identification scores. No overall difference was found between the 2 treatment types except for sounds that had been poorly identified. Articulatory errors with low identification scores made greater progress after receiving mixed training with both production and sound identification training. For error sounds receiving production training, significant relationships were found between both pre- and posttraining identification scores and articulatory improvement, suggesting (a) that perception of error sounds prior to treatment may affect degree of improvement and (b) that production training may improve perception of error sounds. Different views exist with regard to the targeting of stimulable error sounds for treatment. Results of the present study suggest that sound identification in addition to stimulability may be an important consideration in target selection as well as treatment mode.

Final consonant discrimination in children: effects of phonological disorder, vocabulary size, and articulatory accuracy

Preschool-age children with phonological disorders were compared to their typically developing age peers on their ability to discriminate CVC words that differed only in the identity of the final consonant in whole-word and gated conditions. The performance of three age groups of typically developing children and adults was also assessed on the same task. Children with phonological disorders performed more poorly than age-matched peers, and younger typically developing children performed more poorly than older children and adults, even when the entire CVC word was presented. Performance in the whole-word condition was correlated with receptive vocabulary size and a measure of articulatory accuracy across all children. These results suggest that there is a complex relationship among word learning skills, the ability to attend to fine phonetic detail, and the acquisition of articulatory-acoustic and acoustic-auditory representations.

Phonological Awareness and Production

Changes in feature awareness and production during phonological intervention were examined separatelyin four preschool-aged children with severe phonological impairment. Each received intervention that incorporated attention to the features of three error patterns and provided opportunities to practice productions for those patterns. Awareness skills and productionperformance were assessed repeatedly in the context of a multiple-probe design. Relationships between the two variables were then observed. Results indicated that the rate and degree of change in awareness did not always parallel production performance. The findings suggest that both feature awareness and production should be considered when planning intervention.

Listen and Learn? A Software Review of Earobics®

The evaluation of software in the treatment of a language-learning disability requires analysis of both the technical and conceptual aspects of software development. The Earobics® program is reviewed with this dual purpose. The Earobics® program, as reported by the publisher, is an auditory development and phonics software program that is designed to provide auditory processing and phonemic awareness training. Considered first are the technical aspects of the program, including the program description, hardware requirements, and user friendliness. Next, the conceptual framework motivating the software development is assessed through an analysis of the six games that make up the program. These six games appear to be premised on a combination of auditory processing and phonological awareness principles, which are not necessarily compatible. Finally, the strengths and limitations of the program are examined for the developmental sequence presented in its games and utility of the game sequence in the reading acquisition process.

The perception of correctly and incorrectly produced /r/

Twenty-six children and adolescents who were unable to produce /r/ correctly were administered a listening task. They were asked to listen to a tape of 200 words containing /r/ in a variety of contexts. Half of the words had been produced by the subjects themselves and half by another speaker who produced /r/ incorrectly. In addition, half of the words from each speaker contained an /r/ that was incorrect whereas the other half contained an /r/ that was edited so that it sounded correct. Subjects made judgments for each word regarding the correctness of the /r/ and the identity of the speaker. Subjects performed significantly more poorly in judging their own incorrect utterances than on any other category of utterance. When judging their own "corrected" utterances, they were more successful at deciding whether the /r/ was correct than in identifying the identity of the speaker. The results provide support for a relationship between speech perception and production in some individuals with a phonological disorder.

Linear predictive coding parameter manipulation/synthesis of incorrectly produced /r/

This study describes the manipulation and synthesis of LPC parameters to edit incorrectly produced utterances. In particular, it shows that formant frequencies can be manipulated to produce a consistent and reliable change in perception. It also demonstrates that this method can be used to produce quality synthesis of high-pitched voices.

Stimulability: a useful clinical tool

Although difficult to define, stimulability is an easily measured skill that can provide valuable information for clinicians treating children with phonological disorders. In this article, we review changing trends in the definition of stimulability, standardized and nonstandardized approaches to its measurement, and clinical implications of stimulability for prognosis and treatment plan development as they have evolved over a 40-year period. Clinical application of stimulability information in caseload management and intervention is emphasized.

Factors associated with speech-sound stimulability

Speech-sound stimulability as a clinical procedure has been used in speech-language pathology for more than 60 years although review of the archival literature on this clinical construct provides little information on what factors may be associated with it. In this study, the factors found to relate to stimulability were articulation visibility, the child's age, the family's socioeconomic status, and the child's overall imitative abilities. Perception, severity, otitis media history, language abilities, consistency of productions, amount of stimulations provided, and willingness to self-correct were not associated with stimulability. Potential explanations are provided on the basis of prior research.

The specific relation between perception and production errors for place of articulation in developmental apraxia of speech

Developmental apraxia of speech is a disorder of phonological and articulatory output processes. However, it has been suggested that perceptual deficits may contribute to the disorder. Identification and discrimination tasks offer a fine-grained assessment of central auditory and phonetic functions. Seventeen children with developmental apraxia (mean age 8:9, years:months) and 16 control children (mean age 8:0) were administered tests of identification and discrimination of resynthesized and synthesized monosyllabic words differing in place-of-articulation of the initial voiced stop consonants. The resynthetic and synthetic words differed in the intensity of the third formant, a variable potentially enlarging their clinical value. The results of the identification task showed equal slopes for both subject groups, which indicates no phonetic processing deficit in developmental apraxia of speech. The hypothesized effect of the manipulation of the intensity of the third formant of the stimuli was not substantiated. However, the children with apraxia demonstrated poorer discrimination than the control children, which suggests affected auditory processing. Furthermore, analyses of discrimination performance and articulation data per apraxic subject demonstrated a specific relation between the degree to which auditory processing is affected and the frequency of place-of-articulation substitutions in production. This indicates the interdependence of perception and production. The results also suggest that the use of perceptual tasks has significant clinical value.

Perception of voicing cues by children with early otitis media with and without language impairment

Research on the relationship between early otitis media with effusion (OME), language impairment, and central auditory processing has been equivocal. Identification and discrimination tasks provide us with a sensitive method of assessing speech perception on both an auditory and a phonetic level. The present study examined identification and discrimination of initial bilabial stop consonants differing in voicing by 9-year-old children with a history of severe OME. The groups studied were controlled for language impairment. The ability of these children to perceive major and minor voicing cues was examined using multiple voicing cues. Long-term effects of OME were found for both identification and discrimination performance. Children with OME produced an overall inconsistency in categorization, which suggests poorer phonetic processing. Discrimination was measured by means of "just noticeable differences" (JND). Children with early OME experience demonstrated a greater mean JND than children without early OME experience. Finally, in cases of language impairment with early OME, there was no additional deterioration of auditory or phonetic processing. It appears that either early OME or language impairment can lead to poorer perception.

Speech perception training can facilitate sound production learning

This study examined the role of speech perception training in the correction of phonological errors. Twenty-seven preschoolers with phonological impairment who misarticulated /integral of/ were randomly assigned to one of three groups: Group 1 children listened to a variety of correctly and incorrectly produced versions of the word "shoe"; Group 2 children listened to the words "shoe" and "moo"; Group 3 children listened to the words "cat" and "Pete." A computer game was used to provide reinforcement for correct identification of the words. All children received the same traditional sound production training program for correction of their /integral of/ error, concurrently with speech perception training, during six weekly treatment sessions. On post-testing, Group 1 and 2 children demonstrated a superior ability to articulate the target sound in comparison to Group 3 children. The results are interpreted in relation to previous research on this topic.

The perception and production of rhyme in normal and developmentally apraxic children

The phonological competence of four children, aged 5-7 years old, who demonstrated a cluster of symptoms consistent with a diagnosis of developmental apraxia of speech (DAS), was contrasted to that of four normal children. Four rhyming tasks were used to assess the ability of the children to both spontaneously generate rhyming words to targets and to judge the (in)appropriateness of a rhyme in both a word series and forced-choice word pairs. The DAS children revealed a severe deficit in rhyming ability across all tasks and had rhyming abilities markedly inferior to those shown by normal children. The rhyming results were interpreted as possibly indicative of an impoverishment of an internalized phonemic representation system, which precludes accessing and evoking the needed sound image for the vowel + coda for a rhyme. These results, while preliminary in nature, lend support to a conceptualization of DAS as a fundamental disorder of the segmental phonological level of language that impacts on all hierarchically relevant language components. The hypothesis that the underlying etiology of DAS is a developmental dysmorphology of the neural substrates that mediate such basic phonological representational structure is discussed.

Articulation and Phonology

In this addendum to my lead article for this forum, I will resist the temptation to reply to each point of disagreement raised by my colleagues in their commentaries or to emphasize crucial points of agreement. Instead, I will update and clarify my comments on the application of phonological principles to the treatment of children with phonological disorders, responding to their comments only where appropriate to reach these objectives.

Articulation and Phonology

For many speech-language pathologists, the application of the concepts of phonology to the assessment and treatment of phonologically disordered children has produced more confusion than clinical assistance. At least part of this confusion seems to be due to the expectation that, since new terms are being used, new clinical techniques should differ radically from the old ones. The basic intent of this paper is to show that adopting a phonological approach to dealing with speech sound disorders does not necessitate a rejection of the well-established principles underlying traditional approaches to articulation disorders. To the contrary, articulation must be recognized as a critical aspect of speech sound development under any theory. Consequently, phonological principles should be viewed as adding new dimensions and a new perspective to an old problem, not simply as refuting established principles. These new principles have resulted in the development of several procedures that differ in many respects from old procedures, yet are highly similar in others. Whether phonological approaches are better than existing procedures remains an important, but unanswered question.

Relationship between two nontraditional procedures for assessing speech-sound discrimination

Test of speech-sound discrimination are used by special educators, reading specialists and speech-language pathologists in assessing children's ability to differentiate between speech sounds occurring in standard English. Such tests are important in determining if speech-sound articulation errors are caused by difficulty in making such differentiations. However, during the past 10 years, these tests have been criticized on the basis of their reliability and validity. The purpose of this study was to examine the use of two alternative methods of assessing speech-sound discrimination with a school-aged population to determine if they elicited responses in a similar manner.

A second look at tests of speech-sound discrimination

This study is an extension of an earlier study conducted by Bountress and Laderberg (1981), which compared the performances of a group of children on two tests of speech-sound discrimination, the Wepman test and Goldman-Fristoe-Woodcock test. The present study consisted of two treatments: The dual administration of the Boston University Speech Sound Discrimination Test and Wepman, and the Boston and Goldman-Fristoe-Woodcock to two groups of 25 children. An analysis of the results of the two treatments indicated that, as was the case in Bountress and Laderberg's original research comparing the Wepman and Goldman-Fristoe-Woodcock, neither the Boston or Wepman nor the Boston or Goldman-Fristoe-Woodcock comparisons provided evidence that they are comparable measures of speech-sound discrimination. The results of both studies are analyzed, and implications are discussed.

Multiple-phoneme-misarticulating children's perception and production of voice onset time

6 language-impaired misarticulating and 6 normal kindergarten children produced and perceived differences in word-initial stop consonant voicing. Individuals' productive and perceptual phonemic boundaries were similar. No statistically reliable differences were noted between the groups' mean productive or perceptual boundaries. Individual exceptions suggest that some misarticulating , language-impaired children may be inordinately challenged by synthetic speech stimuli or may pass through a developmental stage in which perceptual ability outstrips productive ability.

Auditory perceptual function in relation to phonological development

Auditory perceptual functioning, specifically auditory memory and discrimination, has been historically considered related to linguistic development, in particular phonological development. This fact has resulted in therapy for children with delayed/deviant phonological development being focused on improving auditory memory and discrimination. A number of studies have been carried out over the past few decades to establish whether or not this relationship exists. These studies are reviewed and reasons for the diversity of results discussed. The phonological development of 60 children in relation to their auditory memory and discrimination is described, together with a test of auditory discrimination designed for the purposes of the study.