Density, frequency and the expressive phonology of children with phonological delay

Clinical application of usage-based phonology: Treatment of cleft palate speech using usage-based electropalotography

PURPOSE

To investigate whether a novel electropalatography (EPG) therapy, underpinned by usage-based phonology theory, can improve the accuracy of target speech sounds for school-aged children and adults with persistent speech sound disorder (SSD) secondary to cleft palate +/- lip.

METHOD

Six consecutively treated participants (7-27 years) with long-standing speech disorders associated with cleft palate enrolled in a multiple baseline (ABA) within-participant case series. The usage-based EPG therapy technique involved high-volume production of words. Speech was assessed on three baselines prior to therapy, during weekly therapy, at completion of therapy, and 3 months post-therapy. Percent correct of target phonemes in untreated words and continuously connected speech were assessed through acoustic phonetic transcription. Intra- and inter-transcriber agreement was determined.

RESULT

Large to medium treatment effect sizes were shown for all participants following therapy (15-33 sessions). Percentage of targets correct for untreated words improved from near 0% pre-therapy, to near 100% for most target sounds post-therapy. Generalisation of target sounds to spontaneous connected speech occurred for all participants and ranged from 78.95-100% (M = 90.66; SD = 10.14) 3 months post-therapy.

CONCLUSION

Clinically significant speech change occurred for all participants following therapy. Response to the novel therapeutic technique is encouraging and further research is indicated.

Assessment Methods and Intervention Strategies for Cleft-Related Lateral Misarticulation in Chinese-Speaking Children

The aim of this study was to analyze the characteristics and error speech features of cleft-related lateral misarticulation and provide a basis for clinical evaluation and rational intervention. Participants who were diagnosed with lateral misarticulation after cleft palate repairment were 126 children aged 4, 6 to 16, and 11, and they had complete palatopharyngeal closure, no abnormalities in their speech organs and occlusion, and no hearing or intellectual impairments. The Chinese standard pronunciation clarity word list, the American KAY CSL4500, the Beijing Yangchen YF-16 computer speech analysis workstation, soundproof rooms, Wechsler scales of intelligence-fourth edition, and audiometers were used to evaluate the cleft-related lateral misarticulation. Statistical analysis was performed on the age, gender, error rate, corner of the mouth deviation direction, comorbidity, duration of intervention, period of treatment, and therapeutic effect of concentrated or normal intervention group in different patients. Our results showed that 2 to 3 straight stripes were visible at the onset of consonants /ti:/ /t'i:/, and 3 clear straight lines were visible in /tʂ/, indicating that the lateralized sound had 2 or 3 bursts and lasted for 1 to 2 ms. The onset age of lateralized sound was mostly below 12 years old. Chinese lateralized sound mainly occurred in vowel /i:/, and the occurrence rate of consonants with tongue surface /tɕ]/ /tɕ'/ /ɕ/ was the highest. In addition, the corner of the mouth deviation was also an indicator of lateralization sound, and other types of speech disorders mostly accompanied it. There was a significant difference in the improvement of speech clarity between the concentrated intervention group and the normal group before and after treatment. The 2 groups' average duration and course of treatment were not significantly different. Still, the period of concentrated intervention was shortened considerably, and the speech clarity of both groups of children after treatment exceeded 96%, reaching a normal level.

Promoting Speech Intelligibility in Autism Spectrum Disorder through the Implementation of Phonologically Similar Stimuli

OBJECTIVES

The study focused on promoting expressive phonological skills in 1 Greek-speaking child with autism spectrum disorder (ASD) and comorbid speech sound disorder (SSD). Based on the phonological neighborhood density framework, it was hypothesized that the experimental manipulation through clinical implementation of phonologically overlapping stimuli would yield positive expressive phonology gains relevant to ASD. Participant and Methods: A multiple-baseline single-subject design was implemented. Three baseline sessions measured expressive phonology variables. Sixteen biweekly 30-min intervention sessions were carried out for a period of 2 months. Dependent variables included phonetic inventory size, proportion of consonants correct, occurrences of phonological processes, and percentage of whole word matches elicited via specific word probe stimuli. The Intelligibility in Context Scale was completed by the child's teacher prior to the initiation of intervention and at a follow-up session. Experimental stimuli were grouped together in phonologically dense cohorts.

RESULTS

Comparison between pre-test and post-test measures revealed expressive phonology gains across all measured variables. Follow-up session results showed generalization of expressive phonology gains on untreated targets.

CONCLUSIONS

Significant expressive phonology gains were achieved through the implementation of phonologically similar word stimuli within a systematic intervention protocol with the implementation of specific word-level variables. The findings supported this treatment approach for a child with ASD and SSD, while providing evidence for the phonological density advantage from a cross-linguistic perspective.

Promoting speech intelligibility through phonologically dense targets

This multiple baseline single-case study focused on the implementation of two theoretically motivated models relevant to speech sound disorders (SSD): (1) complexity approach and (2) phonological density neighborhood variable. The complexity approach perspective predicted that complex intervention target stimuli would yield greater phonological gains on more complex targets after systematic phonological intervention. Furthermore, phonologically dense targets would promote speech intelligibility as these stimuli 'tax' productive outputs demand on par with complexity approach. A 4; 6 year-old Greek-speaking male diagnosed with a SSD received phonological intervention for 6 months. Therapy goals included: (1) the reduction of phonological process use and (2) the improvement of output intelligibility. Phonological gains were revealed in cluster reduction leading in increases in the proportion of consonant correct use and improvements in the use of correct whole word matches. Phonological gains were observed for untreated word stimuli. Our findings support the synergistic relationship of Complexity Approach and Phonological Density variable in promoting positive speech outcomes and effectiveness of phonological intervention in the child examined.

Speech Intervention Outcomes Associated With Word Lexicality and Intervention Intensity

Purpose This study examined how lexical representations and intervention intensity affect phonological acquisition and generalization in children with speech sound disorders. Method Using a single-subject multiple baseline design, 24 children with speech sound disorders (3;6 to 6;10 [years;months]) were split into 3 word lexicality types targeting word-initial complex singleton phonemes: /ɹ l ʧ θ/. Specifically, academic vocabulary words, nonwords (NWs), and high-frequency (HF) words were contrasted. Intervention intensity was examined by comparing the performance of 12 children who completed eleven 50-min sessions (4 children/word type) to the performance of 12 who completed 19 sessions (4 children/word type). Children's production accuracy of their treated phonemes and overall percent consonants correct values were used to measure phonological generalization via percentage accuracy scores and d scores. Results All word lexicality conditions elicited phonological change, suggesting that academic vocabulary words, NWs, and HF words are viable intervention targets. Group mean averages were similarly high for the NWs and HF words, although children in the NW condition demonstrated more consistent phonological gains. Children who received 19 intervention sessions achieved 6 times more gains in treated sound accuracy than did children who received 11 sessions. Conclusions Word lexicality did not significantly influence children's intervention outcomes. More intensive intervention, as characterized by the number sessions, resulted in greater phonological change than did a shorter intervention program. Intervention intensity outcomes should be considered when establishing best practices for speech intervention scheduling. Supplemental Material https://doi.org/10.23641/asha.7336055.

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

Neighborhood Density and Syntactic Class Effects on Spoken Word Recognition: Specific Language Impairment and Typical Development

PURPOSE

The purpose of the current study was to determine the effect of neighborhood density and syntactic class on word recognition in children with specific language impairment (SLI) and typical development (TD).

METHOD

Fifteen children with SLI (M age = 6;5 [years;months]) and 15 with TD (M age = 6;4) completed a forward gating task that presented consonant-vowel-consonant dense and sparse (neighborhood density) nouns and verbs (syntactic class).

RESULTS

On all dependent variables, the SLI group performed like the TD group. Recognition performance was highest for dense words and nouns. The majority of 1st nontarget responses shared the 1st phoneme with the target (i.e., was in the target's cohort). When considering the ranking of word types from easiest to most difficult, children showed equivalent recognition performance for dense verbs and sparse nouns, which were both easier to recognize than sparse verbs but more difficult than dense nouns.

CONCLUSION

The current study yields new insight into how children access lexical-phonological information and syntactic class during the process of spoken word recognition. Given the identical pattern of results for the SLI and TD groups, we hypothesize that accessing lexical-phonological information may be a strength for children with SLI. We also discuss implications for using the forward gating paradigm as a measure of word recognition.

Nexus to Lexis: Phonological Disorders in Children

Research on phonological disorders in children has conventionally emphasized the speech sound in search of causes, diagnoses, treatments, and prevention of the disorder. This article aims to shift the research focus to the word instead. The motivation comes from advances in psycholinguistics that demonstrate the word is central to the perception, production, and acquisition of phonological information. Three strands of potential study are outlined in evaluation of how words might initiate and boost, but perhaps also, interrupt learning for children with phonological disorders.

Lexical Considerations in the Treatment of Speech Sound Disorders in Children

The interaction between lexical and phonological development has been the focus of a growing body of research. Findings suggest that phonological ability influences word learning and that certain characteristics of words influence how words are produced by children. This article summarizes research findings regarding the effects of word frequency, phonological neighborhood density (PND), and phonotactic probability (PP) on phonological development, and describes how these factors have been manipulated to influence phonological learning in the treatment of speech sound disorder in children. Clinical applications and ideas for considering lexical factors in the selection of target words for treatment are provided.

Effect Size for Single-Subject Design in Phonological Treatment

PURPOSE

The purpose of this study was to document, validate, and corroborate effect size (ES) for single-subject design in treatment of children with functional phonological disorders; to evaluate potential child-specific contributing variables relative to ES; and to establish benchmarks for interpretation of ES for the population.

METHOD

Data were extracted from the Developmental Phonologies Archive for 135 preschool children with phonological disorders who previously participated in single-subject experimental treatment studies. Standard mean difference(all with correction for continuity) was computed to gauge the magnitude of generalization gain that accrued longitudinally from treatment for each child with the data aggregated for purposes of statistical analyses.

RESULTS

ES ranged from 0.09 to 27.83 for the study population. ES was positively correlated with conventional measures of phonological learning and visual inspection of learning data on the basis of procedures standard to single-subject design. ES was linked to children's performance on diagnostic assessments of phonology but not other demographic characteristics or related linguistic skills and nonlinguistic skills. Benchmarks for interpretation of ES were estimated as 1.4, 3.6, and 10.1 for small, medium, and large learning effects, respectively.

CONCLUSION

Findings have utility for single-subject research and translation of research to evidence-based practice for children with phonological disorders.

Dense neighborhoods and mechanisms of learning: evidence from children with phonological delay

There is a noted advantage of dense neighborhoods in language acquisition, but the learning mechanism that drives the effect is not well understood. Two hypotheses--long-term auditory word priming and phonological working memory--have been advanced in the literature as viable accounts. These were evaluated in two treatment studies enrolling twelve children with phonological delay. Study 1 exposed children to dense neighbors versus non-neighbors before training sound production in evaluation of the priming hypothesis. Study 2 exposed children to the same stimuli after training sound production as a test of the phonological working memory hypothesis. Results showed that neighbors led to greater phonological generalization than non-neighbors, but only when presented prior to training production. There was little generalization and no differential effect of exposure to neighbors or non-neighbors after training production. Priming was thus supported as a possible mechanism of learning behind the dense neighborhood advantage in phonological acquisition.

Understanding the developing sound system: interactions between sounds and words

Over the course of the first 2 years of life, infants are learning a great deal about the sound system of their native language. Acquiring the sound system requires the infant to learn about sounds and their distributions, sound combinations, and prosodic information, such as syllables, rhythm, and stress. These aspects of the phonological system are being learned simultaneously as the infant experiences the language around him or her. What binds all of the phonological units is the context in which they occur, namely, words. In this review, we explore the development of phonetics and phonology by showcasing the interactive nature of the developing lexicon and sound system with a focus on perception. We first review seminal research in the foundations of phonological development. We then discuss early word recognition and learning followed by a discussion of phonological and lexical representations. We conclude by discussing the interactive nature of lexical and phonological representations and highlight some further directions for exploring the developing sound system. WIREs Cogn Sci 2014, 5:589-602. doi: 10.1002/wcs.1307 For further resources related to this article, please visit the WIREs website.

CONFLICT OF INTEREST

The authors have declared no conflicts of interest for this article.

How to meet the neighbors: Modality effects on phonological generalization

Long-term auditory priming of words from dense neighborhoods has been posited as a learning mechanism that affects change in the phonological structure of children's lexical representations. An apparent confound associated with the modality of priming responsible for structural change has been introduced in the literature, which challenges this proposal. Thus, our purpose was to evaluate prime modality in the treatment of children with phonological delay. Nine children were assigned to auditory-visual, auditory, or visual priming of words from dense neighborhoods prior to the treatment of production as the independent variable. The dependent variable was phonological generalization. Results showed that auditory priming (with or without visual input) promoted greater generalization on an order of magnitude of 3:1. Findings support the theoretical significance of auditory priming for phonological learning and demonstrate the applied utility of priming in clinical treatment.

Grammatical treatment and specific language impairment: neighbourhood density & third person singular -s

The purpose of this study was to test the effect of manipulating verb neighbourhood density in treatment targeting the third person singular lexical affix. Using a single-subject experimental design, six pre-schoolers with Specific Language Impairment (SLI) were randomly assigned to one of two conditions: (1) treatment with sparse verbs or (2) treatment with dense verbs in 12 sessions. The third person singular lexical affix was targeted for 12 sessions of treatment in both conditions. Treatment gain and generalization were measured as the dependent variables. Third person singular % correct change from pre-treatment to post-treatment was measured using sentence production tasks with comparisons across the two treatment conditions. Treatment gain and generalization were greater for children enrolled in the sparse condition. Preliminary clinical recommendations are made and theoretical implications are discussed relative to neighbourhood density effects on lexical activation and storage in children with SLI.