Central timing deficits in subtypes of primary speech disorders

Acoustic Analysis of Spatiotemporal Variability in Children With Childhood Apraxia of Speech

PURPOSE

The purpose of this study was to investigate acoustic spatiotemporal variability in children with childhood apraxia of speech (CAS) compared to children with typical development (TD). Increased spatiotemporal variability in children with CAS relative to nonapraxic peers has been documented in multiple kinematic studies. To date, few studies have investigated spatiotemporal variability in CAS using an acoustic signal.

METHOD

Data were drawn from 10 children with CAS and 10 children with TD, ranging in age from 5;0 to 11;2 (years;months), who participated in an online study. All children with CAS had a verified diagnosis and showed at least five CAS features across at least two tasks, independently confirmed by two speech-language pathologists with expertise in CAS. Children repeated the sentences "Buy Bobby a puppy" (BBAP) and "Mom pets the puppy" (MPP) 10 times each. The acoustic spatiotemporal index (STI), calculated from the amplitude envelope, was used to investigate acoustic spatiotemporal variability. Using a regression analysis, we analyzed group differences in STI values while controlling for age and gender.

RESULTS

Children with CAS did not produce enough usable tokens of BBAP to analyze. MPP revealed significantly higher acoustic STI values in children with CAS compared to children with TD. No significant effects were observed for age or gender. Acoustic data collected online without the use of specialized equipment yielded high-quality audio data from which amplitude envelope tracing could be reliably accomplished.

CONCLUSIONS

This study adds to a growing body of empirical data indicating that children with CAS produce speech with more variable spatiotemporal control compared to children with TD. In addition to producing more variable speech, children with CAS were less consistently able to form productions free of phonetic errors. These findings also demonstrate the feasibility of using remote data collection to investigate acoustic spatiotemporal variability, which allows for the recruitment of larger samples of low-incidence populations.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.26814883.

Development of the Digital Speech Assessment Instrument

OBJECTIVE

This study aimed to develop a Digital Speech Assessment Instrument to evaluate the phonological and motor speech skills of Brazilian Portuguese-speaking children and adolescents through six tasks: (a) word naming, (b) word imitation, (c) pseudoword imitation, (d) word repetition, (e) pseudoword repetition, and (f) diadochokinesis.

METHOD

The assessment instrument was developed and validated in a seven-step process, beginning with stimulus selection and ending with Pilot Study 1 (involving children and adolescents with typical speech development) and Pilot Study 2 (involving children and adolescents with speech sound disorders [SSDs]). Participants of the study included expert and nonexpert judges, children, and adolescents.

RESULTS

The Digital Speech Assessment Instrument contains 91 real words (61 in the naming task, 51 in the imitation task, and five in the repetition task), 26 pseudowords (26 in the imitation task and four in the repetition task), and six stimuli for diadochokinesis. The test contains stimuli in the form of images as well as audio and video recordings and allows for the analysis and storage of participant data in a virtual database.

CONCLUSIONS

This study described the development of the Digital Speech Assessment Instrument, available in Brazilian Portuguese for the evaluation of several aspects of speech production (including word and pseudoword naming, imitation, and repetition and diadochokinesis). The test was developed for children aged 2;0 (years;months) to 17;11 and is administered fully online. In the future, the instrument can be used to provide a timely and accurate diagnosis of SSDs.

Manual Rhythmic Sequencing Skills in Children With Childhood Apraxia of Speech

PURPOSE

Rhythm is one procedural mechanism that underlies language and motor skill acquisition and has been implicated in children with childhood apraxia of speech (CAS). The purpose of this study is to investigate manual rhythmic sequencing skills in children with a history of or current CAS (hx/CAS) compared to children with typical development (TD).

METHOD

Thirty-eight children (18 with hx/CAS, 20 with TD), ages 5;0-12;8 (years;months), from across the United States participated in an online study. Participants imitated two rhythms in two different conditions, clapping and tapping. We assessed overall accuracy, mean number of beats, pause marking, and rhythmic sequence variability using the Mann-Whitney U test. Effect sizes were calculated to examine the influence of coordinative complexity on performance.

RESULTS

Compared to children with TD, children with hx/CAS marked fewer trials with a pause in both conditions of the easier rhythm and showed lower overall accuracy and more variable rhythmic sequences in both rhythms and conditions. The mean number of beats produced by children with hx/CAS and children with TD did not differ in three out of four rhythms/conditions. Unlike children with TD, children with hx/CAS showed little improvement from clapping to tapping across most dependent measures; reducing coordination demands did not improve performance in children with hx/CAS.

CONCLUSIONS

We found that children with hx/CAS show manual rhythmic deficits that are similar to the deficits they display in speech. These findings provide support for a domain-general cognitive mechanisms account of the rhythmic deficits observed across linguistic and nonlinguistic tasks in children with hx/CAS.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.24052821.

Differential Diagnosis of Apraxia of Speech in Children and Adults: A Scoping Review

Purpose Despite having distinct etiologies, acquired apraxia of speech (AOS) and childhood apraxia of speech (CAS) share the same central diagnostic challenge (i.e., isolating markers specific to an impairment in speech motor planning/programming). The purpose of this review was to evaluate and compare the state of the evidence on approaches to differential diagnosis for AOS and CAS and to identify gaps in each literature that could provide directions for future research aimed to improve clinical diagnosis of these disorders. Method We conducted a scoping review of literature published between 1997 and 2019, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines. For both AOS and CAS, literature was charted and summarized around four main methodological approaches to diagnosis: speech symptoms, quantitative speech measures, impaired linguistic-motor processes, and neuroimaging. Results Results showed that similar methodological approaches have been used to study differential diagnosis of apraxia of speech in adults and children; however, the specific measures that have received the most research attention differ between AOS and CAS. Several promising candidate markers for AOS and CAS have been identified; however, few studies report metrics that can be used to assess their diagnostic accuracy. Conclusions Over the past two decades, there has been a proliferation of research identifying potential diagnostic markers of AOS and CAS. In order to improve clinical diagnosis of AOS and CAS, there is a need for studies testing the diagnostic accuracy of multiple candidate markers, better control over language impairment comorbidity, more inclusion of speech-disordered control groups, and an increased focus on translational work moving toward clinical implementation of promising measures.

Differences Between School-Aged Children with Apraxia of Speech and Other Speech Sound Disorders on Multisyllable Repetition

PURPOSE

To evaluate whether features of childhood apraxia of speech identified in previous literature could be replicated in a sample of school-age children.

METHOD

A literature review was conducted to identify candidate speech features that have been previously considered when differentiating childhood apraxia of speech from other types of speech sound disorders. The candidate features recoverable from blinded transcriptions of multisyllable word repetitions (MSWR) were applied to a cohort of 61 children, aged 7-17, previously classified as having childhood apraxia of speech (n=21) or non-CAS Speech Sound Disorder (SSD, n=40).

RESULTS

One hundred and ninety-four features had been explored in previous literature to assess their ability to differentiate CAS from other SSDs. Fifteen perceptual features were selected from this list to be applied to performance on the MSWR. In this sample, children with CAS differed from children with SSD on the prevalence of voicing changes, percent of structurally correct words, correct lexical stress, and syllable deletions within a speech corpus derived from the MSWR task.

CONCLUSION

Although previous literature points to numerous features as differentiating CAS from other SSDs, only a portion of those features were replicated in this sample of school-age children. Features of CAS that affect segmental accuracy, prosody and word structure may be likely to persist into late childhood and early adolescence.

Preliminary Evidence That Motor Planning Is Slower and More Difficult for Children With Autism Spectrum Disorder During Motor Cooperation

Children with autism spectrum disorder (ASD) exhibit impairment in helping someone else with a motor action, which may arise from impairment in selecting and preparing motor responses. Five children with ASD and five typically developing children performed a cooperative motor planning task that required them to reach for, lift, and hand an object (hammer or stick) to a researcher. The response, movement, and grasp time were measured. Children with ASD grasped the object longer on trials where they helped, indicating that the action was planned in sequence versus as a whole (i.e., prior to the onset of movement). The hammer object elicited a quicker response than the stick, suggesting the facilitation of planning by tools with inherent action properties. Finally, the increased helping of children with ASD was not mirrored by changes in the response, movement, or grasp time.

Vowel Duration Discrimination of Children With Childhood Apraxia of Speech: A Preliminary Study

Purpose The ability of 5- and 6-year-old male children (23 participants) between the chronological ages of 5;0 and 6;11 (years;months) with childhood apraxia of speech (CAS; n = 9) and with typical development (TD; n = 14) to detect differences in vowel duration of syllable pairs is explored. We asked whether the children with CAS show different patterns of performance on the vowel duration difference experimental task than those of their similarly aged peers with TD. Method A male adult audio-recorded the syllable /bɑ/. The /ɑ/ was digitally lengthened and shortened, while maintaining uniform fundamental frequency and amplitude of the vowel and duration of the consonant /b/ at 42 ms. Vowel lengths increased in 40-ms increments, ranging from 208 to 488 ms. Eight pairs of syllables, 1 with equal length and 7 with differing vowel lengths, were randomly presented to the children 10 times in blocks of 16 pairs via a computer application. Results Numerous complementary analyses indicated patterns of performance differed for children with CAS compared to the children with TD. The children with CAS were notably less accurate in their duration discrimination and evidenced greater variability in their performances across duration difference conditions than their peers with TD, signifying they were generally challenged to discriminate the vowel duration differences. Conclusion These results suggest that CAS, which is more generally considered a motor speech disorder, may have a perceptual component of CAS related to vowel duration discrimination. Further research directions and clinical implications are discussed. Supplemental Material https://doi.org/10.23641/asha.8411876.

Working memory in school-age children with and without a persistent speech sound disorder

PURPOSE

The aim of this study was to explore the role of working memory processes as a possible cognitive underpinning of persistent speech sound disorders (SSD).

METHOD

Forty school-aged children were enrolled; 20 children with persistent SSD (P-SSD) and 20 typically developing children. Children participated in three working memory tasks - one to target each of the components in Baddeley's working memory model: phonological loop, visual spatial sketchpad and central executive.

RESULT

Children with P-SSD performed poorly only on the phonological loop tasks compared to their typically developing age-matched peers. However, mediation analyses revealed that the relation between working memory and a P-SSD was reliant upon nonverbal intelligence.

CONCLUSION

These results suggest that co-morbid low-average nonverbal intelligence are linked to poor working memory in children with P-SSD. Theoretical and clinical implications are discussed.

Performance of children with speech sound disorders in the dynamic evaluation of motor speech skills

Purpose To compare performance between children with typical speech acquisition, phonological disorders, and childhood apraxia of speech for the variables overall articulatory accuracy and consistency of the Dynamic Evaluation of Motor Speech Skill - Brazilian Portuguese version (DEMSS-BR). Methods Study participants were 18 children of both genders aged 4 years and 6 months to 5 years and 8 months. The sample was divided into three groups: six children with typical speech acquisition (TSA), six children with phonological disorder (PD), and six individuals with childhood apraxia of speech (CAS). All participants were submitted to the DEMSS-BR and had their subscores of speech accuracy and consistency measured. Performance comparison between the groups was statistically evaluated using the Mann-Whitney U Test. Results Participants in the group with CAS presented poorer performance for the variables overall articulatory accuracy and consistency compared with those of participants in the other two groups. Conclusion The group of children with childhood apraxia of speech presented poorer performance on the DEMSS-BR compared with those of the groups with typical speech acquisition and phonological disorders. The study demonstrated that the DEMSS-BR assists with differential diagnosis of children with speech sound disorders.

Don't speak too fast! Processing of fast rate speech in children with specific language impairment

Background

Perception of speech rhythm requires the auditory system to track temporal envelope fluctuations, which carry syllabic and stress information. Reduced sensitivity to rhythmic acoustic cues has been evidenced in children with Specific Language Impairment (SLI), impeding syllabic parsing and speech decoding. Our study investigated whether these children experience specific difficulties processing fast rate speech as compared with typically developing (TD) children.

Method

Sixteen French children with SLI (8–13 years old) with mainly expressive phonological disorders and with preserved comprehension and 16 age-matched TD children performed a judgment task on sentences produced 1) at normal rate, 2) at fast rate or 3) time-compressed. Sensitivity index (d′) to semantically incongruent sentence-final words was measured.

Results

Overall children with SLI perform significantly worse than TD children. Importantly, as revealed by the significant Group × Speech Rate interaction, children with SLI find it more challenging than TD children to process both naturally or artificially accelerated speech. The two groups do not significantly differ in normal rate speech processing.

Conclusion

In agreement with rhythm-processing deficits in atypical language development, our results suggest that children with SLI face difficulties adjusting to rapid speech rate. These findings are interpreted in light of temporal sampling and prosodic phrasing frameworks and of oscillatory mechanisms underlying speech perception.

Speech and nonspeech: What are we talking about?

Understanding of the behavioural, cognitive and neural underpinnings of speech production is of interest theoretically, and is important for understanding disorders of speech production and how to assess and treat such disorders in the clinic. This paper addresses two claims about the neuromotor control of speech production: (1) speech is subserved by a distinct, specialised motor control system and (2) speech is holistic and cannot be decomposed into smaller primitives. Both claims have gained traction in recent literature, and are central to a task-dependent model of speech motor control. The purpose of this paper is to stimulate thinking about speech production, its disorders and the clinical implications of these claims. The paper poses several conceptual and empirical challenges for these claims - including the critical importance of defining speech. The emerging conclusion is that a task-dependent model is called into question as its two central claims are founded on ill-defined and inconsistently applied concepts. The paper concludes with discussion of methodological and clinical implications, including the potential utility of diadochokinetic (DDK) tasks in assessment of motor speech disorders and the contraindication of nonspeech oral motor exercises to improve speech function.

Motor and verbal perspective taking in children with Autism Spectrum Disorder: Changes in social interaction with people and tools

BACKGROUND

Children with Autism Spectrum Disorder (ASD) have difficulty communicating with others nonverbally, via mechanisms such as hand gestures, eye contact and facial expression. Individuals with ASD also have marked deficits in planning future actions (Hughes, 1996), which might contribute to impairments in non-verbal communication. Perspective taking is typically assessed using verbal scenarios whereby the participant imagines how an actor would interact in a social situation (e.g., Sally Anne task; Baron-Cohen, Leslie, & Frith, 1985).

METHOD

The current project evaluated motor perspective taking in five children with ASD (8-11 years old) as they participated in a narrative intervention program over the course of about 16 weeks. The goal of the motor perspective-taking task was to facilitate the action of an experimenter either hammering with a tool or putting it away.

RESULTS

Initially, children with ASD facilitated the experimenter's action less than neurotypical control children. As the narrative intervention progressed, children with ASD exhibited increased motor facilitation that paralleled their increased use of mental state and causal language, indicating a link between verbal and motor perspective taking.

CONCLUSIONS

Motoric perspective taking provides an additional way to assess understanding and communication in children with ASD and may be a valuable tool for both early assessment and diagnosis of children with ASD.

A Diagnostic Marker to Discriminate Childhood Apraxia of Speech From Speech Delay: I. Development and Description of the Pause Marker

Purpose

The goal of this article (PM I) is to describe the rationale for and development of the Pause Marker (PM), a single-sign diagnostic marker proposed to discriminate early or persistent childhood apraxia of speech from speech delay.

Method

The authors describe and prioritize 7 criteria with which to evaluate the research and clinical utility of a diagnostic marker for childhood apraxia of speech, including evaluation of the present proposal. An overview is given of the Speech Disorders Classification System, including extensions completed in the same approximately 3-year period in which the PM was developed.

Results

The finalized Speech Disorders Classification System includes a nosology and cross-classification procedures for childhood and persistent speech disorders and motor speech disorders (Shriberg, Strand, & Mabie, 2017). A PM is developed that provides procedural and scoring information, and citations to papers and technical reports that include audio exemplars of the PM and reference data used to standardize PM scores are provided.

Conclusions

The PM described here is an acoustic-aided perceptual sign that quantifies one aspect of speech precision in the linguistic domain of phrasing. This diagnostic marker can be used to discriminate early or persistent childhood apraxia of speech from speech delay.

Instrumentos para avaliação de apraxia de fala infantil

RESUMO Objetivo: Revisar sistematicamente na literatura os principais instrumentos utilizados para avaliação da apraxia de fala infantil. Estratégia de pesquisa: Realizou-se busca nas bases Scopus, PubMed e Embase Critérios de seleção: Foram selecionados estudos empíricos que utilizaram instrumentos de avaliação da apraxia de fala infantil. Análise dos dados: A seleção dos artigos foi realizada por dois pesquisadores independentes. Resultados: Foram encontrados 695 resumos. Após a leitura dos resumos, foram selecionados 12 artigos completos. Foi possível identificar cinco instrumentos: Verbal Motor Production Assessment for Children, Dynamic Evaluation of Motor Speech Skill , The Orofacial Praxis Test , Kaufman Speech Praxis Test for children e o Madison Speech Assessment Protocol . São poucos os instrumentos utilizados para identificação da apraxia de fala infantil e a maioria destina-se à avaliação da realização de praxias e/ou movimentos orofaciais, sequências de movimentos orofaciais, articulação de fonemas simples, fonemas complexos e sílabas, fala espontânea, além da adequação da prosódia. Conclusões: Percebe-se que existem instrumentos que se propõem a avaliar e diagnosticar a apraxia de fala infantil. No entanto, ainda são escassos os estudos sobre esse tema em nível nacional, bem como protocolos padronizados e validados para a população brasileira que avaliem e ajudem em um diagnóstico preciso.

Non-verbal sensorimotor timing deficits in children and adolescents who stutter

There is growing evidence that motor and speech disorders co-occur during development. In the present study, we investigated whether stuttering, a developmental speech disorder, is associated with a predictive timing deficit in childhood and adolescence. By testing sensorimotor synchronization abilities, we aimed to assess whether predictive timing is dysfunctional in young participants who stutter (8-16 years). Twenty German children and adolescents who stutter and 43 non-stuttering participants matched for age and musical training were tested on their ability to synchronize their finger taps with periodic tone sequences and with a musical beat. Forty percent of children and 90% of adolescents who stutter displayed poor synchronization with both metronome and musical stimuli, falling below 2.5% of the estimated population based on the performance of the group without the disorder. Synchronization deficits were characterized by either lower synchronization accuracy or lower consistency or both. Lower accuracy resulted in an over-anticipation of the pacing event in participants who stutter. Moreover, individual profiles revealed that lower consistency was typical of participants that were severely stuttering. These findings support the idea that malfunctioning predictive timing during auditory-motor coupling plays a role in stuttering in children and adolescents.

Functional MRI evidence for fine motor praxis dysfunction in children with persistent speech disorders

Children with persistent speech disorders (PSD) often present with overt or subtle motor deficits; the possibility that speech disorders and motor deficits could arise from a shared neurological base is currently unknown. Functional MRI (fMRI) was used to examine the brain networks supporting fine motor praxis in children with PSD and without clinically identified fine motor deficits.

METHODS

This case-control study included 12 children with PSD (mean age 7.42 years, four female) and 12 controls (mean age 7.44 years, four female). Children completed behavioral evaluations using standardized motor assessments and parent reported functional measures. During fMRI scanning, participants completed a cued finger tapping task contrasted passive listening. A general linear model approach identified brain regions associated with finger tapping in each group and regions that differed between groups. The relationship between regional fMRI activation and fine motor skill was assessed using a regression analysis.

RESULTS

Children with PSD had significantly poorer results for rapid speech production and fine motor praxis skills, but did not differ on classroom functional skills. Functional MRI results showed that children with PSD had significantly more activation in the cerebellum during finger tapping. Positive correlations between performance on a fine motor praxis test and activation multiple cortical regions were noted for children with PSD but not for controls.

CONCLUSIONS

Over-activation in the cerebellum during a motor task may reflect a subtle abnormality in the non-speech motor neural circuitry in children with PSD.

Tapped out: do people with aphasia have rhythm processing deficits?

PURPOSE

In this study, the authors tested whether people with aphasia (PWAs) show an impaired ability to process rhythm, both in terms of perception and production.

METHOD

Two experiments were conducted. In Experiment 1, 16 PWAs and 15 age-matched control participants performed 3 rhythm tasks: tapping along to short rhythms, tapping these same rhythms from memory immediately after presentation, and making same-different judgments about pairs of tapped rhythms that they heard. Comparison tasks measured same-different judgment ability with visual stimuli and nonverbal working memory (Corsi blocks). In Experiment 2, 14 PWAs and 16 control participants made same-different judgments for pairs of auditory stimuli that differed in terms of rhythm or pitch (for comparison).

RESULTS

In Experiment 1, PWAs performed worse than control participants across most measures of rhythm processing. In contrast, PWAs and control participants did not differ in their performance on the comparison tasks. In Experiment 2, the PWAs performed worse than control participants across all conditions but with a more marked deficit in stimulus pairs that differed in rhythm than in those that differed in pitch.

CONCLUSIONS

The results support the hypothesis that at least some PWAs exhibit deficits of rhythm and timing. This may have implications for treatments involving tapping or other rhythmic cues.

A motor speech assessment for children with severe speech disorders: reliability and validity evidence

PURPOSE

In this article, the authors report reliability and validity evidence for the Dynamic Evaluation of Motor Speech Skill (DEMSS), a new test that uses dynamic assessment to aid in the differential diagnosis of childhood apraxia of speech (CAS).

METHOD

Participants were 81 children between 36 and 79 months of age who were referred to the Mayo Clinic for diagnosis of speech sound disorders. Children were given the DEMSS and a standard speech and language test battery as part of routine evaluations. Subsequently, intrajudge, interjudge, and test-retest reliability were evaluated for a subset of participants. Construct validity was explored for all 81 participants through the use of agglomerative cluster analysis, sensitivity measures, and likelihood ratios.

RESULTS

The mean percentage of agreement for 171 judgments was 89% for test-retest reliability, 89% for intrajudge reliability, and 91% for interjudge reliability. Agglomerative hierarchical cluster analysis showed that total DEMSS scores largely differentiated clusters of children with CAS vs. mild CAS vs. other speech disorders. Positive and negative likelihood ratios and measures of sensitivity and specificity suggested that the DEMSS does not overdiagnose CAS but sometimes fails to identify children with CAS.

CONCLUSIONS

The value of the DEMSS in differential diagnosis of severe speech impairments was supported on the basis of evidence of reliability and validity.

Oral and hand movement speeds are associated with expressive language ability in children with speech sound disorder

This study tested the hypothesis that children with speech sound disorder have generalized slowed motor speeds. It evaluated associations among oral and hand motor speeds and measures of speech (articulation and phonology) and language (receptive vocabulary, sentence comprehension, sentence imitation), in 11 children with moderate to severe SSD and 11 controls. Syllable durations from a syllable repetition task served as an estimate of maximal oral movement speed. In two imitation tasks, nonwords and clapped rhythms, unstressed vowel durations and quarter-note clap intervals served as estimates of oral and hand movement speed, respectively. Syllable durations were significantly correlated with vowel durations and hand clap intervals. Sentence imitation was correlated with all three timed movement measures. Clustering on syllable repetition durations produced three clusters that also differed in sentence imitation scores. Results are consistent with limited movement speeds across motor systems and SSD subtypes defined by motor speeds as a corollary of expressive language abilities.

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.

A multigenerational family study of oral and hand motor sequencing ability provides evidence for a familial speech sound disorder subtype

PURPOSE: To evaluate phenotypic expressions of speech sound disorder (SSD) in multigenerational families with evidence of familial forms of SSD. METHOD: Members of five multigenerational families (N = 36) produced rapid sequences of monosyllables and disyllables and tapped computer keys with repetitive and alternating movements. RESULTS: Measures of repetitive and alternating motor speed were correlated within and between the two motor systems. Repetitive and alternating motor speeds increased in children and decreased in adults as a function of age. In two families with children who had severe speech deficits consistent with disrupted praxis, slowed alternating, but not repetitive, oral movements characterized most of the affected children and adults with a history of SSD, and slowed alternating hand movements were seen in some of the biologically related participants as well. CONCLUSION: Results are consistent with a familial motor-based SSD subtype with incomplete penetrance, motivating new clinical questions about motor-based intervention not only in the oral but also the limb system.

Aerodynamic indices of velopharyngeal function in childhood apraxia of speech

Childhood apraxia of speech (CAS) is characterized as a deficit in the motor processes of speech for the volitional control of the articulators, including the velum. One of the many characteristics attributed to children with CAS is intermittent or inconsistent hypernasality. The purpose of this study was to document differences in velopharyngeal function in children diagnosed with CAS from children with typically-developing speech. Pressure-flow techniques were used to estimate the velopharyngeal port size and measure the temporal sequencing of airflow and pressure events associated with production of a nasal + oral plosive sequence in the speech of three children with CAS and three age-matched comparison participants. The results of this pilot study revealed significant differences between the performance of the CAS group and the comparison group in three timing measures of velopharyngeal port closure and velopharyngeal orifice area during speech.

Octave-shifted pitch matching in nonword imitations: the effects of lexical stress and speech sound disorder

Perceptual similarities of musical tones separated by octave intervals are known as octave equivalence (OE). Peter et al. [(2008). Proceedings of the Fourth Conference on Speech Prosody, edited S. Maduerira, C. Reis, and P. Barbosa, Luso-Brazilian Association of Speech Sciences, Campinas, pp. 731-734] found evidence of octave-shifted pitch matching (OSPM) in children during verbal imitation tasks, implying OE in speech tokens. This study evaluated the role of lexical stress and speech sound disorder (SSD) in OSPM. Eleven children with SSD and 11 controls imitated low-pitched nonwords. Stimulus/response f(0) ratios were computed. OSPM was expressed preferentially in stressed vowels. SSD was associated with reduced expression of OSPM in unstressed vowels only. Results are consistent with the psycholinguistic prominence of lexical stress and prosodic deficits in SSD.

Speed and accuracy of rapid speech output by adolescents with residual speech sound errors including rhotics

Children with residual speech sound errors are often underserved clinically, yet there has been a lack of recent research elucidating the specific deficits in this population. Adolescents aged 10-14 with residual speech sound errors (RE) that included rhotics were compared to normally speaking peers on tasks assessing speed and accuracy of speech production. The two groups were evaluated on an oral diadochokinetic task, which required rapid production of the trisyllable /p Lambda t Lambda k Lambda/, and two rapid naming tasks: monosyllabic letter names and multisyllabic picture names. No significant group differences were observed in the speed of trisyllables on the DDK task, whether examining all attempts or only correct productions. However, the RE group was less accurate and more variable in their production of the trisyllables. In addition, the RE group was slower and phonologically less accurate in rapidly naming multisyllabic pictures, but not in naming letters. A combination of speed and accuracy measures from these tasks revealed relatively little overlap between groups. Results suggest that both speed and accuracy may be impaired in adolescents with RE, although the underlying causal mechanisms require further exploration.