Motor Speech Disorders Research Articles

Motor or non-motor speech interference? A multimodal fMRI and direct cortical stimulation mapping study

We retrospectively analyzed data from 15 patients, with a normal pre-operative cognitive performance, undergoing awake surgery for left fronto-temporal low-grade glioma. We combined a pre-surgical measure (fMRI maps of motor- and language-related centers) with intra-surgical measures (MNI-registered cortical sites data obtained during intra-operative direct electrical stimulation, DES, while they performed the two most common language tasks: number counting and picture naming).Selective DES effects along the precentral gyrus/inferior frontal gyrus (and/or the connected speech articulation network) were obtained. DES of the precentral gyrus evoked the motor speech arrest, i.e., anarthria (with apparent mentalis muscle movements). We calculated the number of shared voxels between the lip-tongue and overt counting related- and silent naming-related fMRI maps and the Volumes of Interest (VOIs) obtained by merging together the MNI sites at which a given speech disturbance was observed, normalized on their mean the values (i.e., Z score). Both tongue- and lips-related movements fMRI maps maximally overlapped (Z = 1.05 and Z = 0.94 for lips and tongue vs. 0.16 and −1.003 for counting and naming) with the motor speech arrest seed. DES of the inferior frontal gyrus, pars opercularis and the rolandic operculum induced speech arrest proper (without apparent mentalis muscle movements). This area maximally overlapped with overt counting-related fMRI map (Z = −0.11 and Z = 0.09 for lips and tongue vs. 0.9 and 0.0006 for counting and naming). Interestingly, our fMRI maps indicated reduced Broca's area activity during silent speech compared to overt speech. Lastly, DES of the inferior frontal gyrus, pars opercularis and triangularis evoked variations of the output, i.e., dysarthria, a motor speech disorder occurring when patients cannot control the muscles used to produce articulated sounds (phonemes). Silent object naming-related fMRI map maximally overlapped (Z = −0.93 and Z = −1.04 for lips and tongue vs. −1.07 and 0.99 for counting and naming) with this seed.Speech disturbances evoked by DES may be thought of as selective interferences with specific recruitment of left inferior frontal gyrus and precentral cortex which are differentiable in terms of the specific interference induced.

Exploring Motor Speech Disorders in Low and Minimally Verbal Autistic Individuals: An Auditory-Perceptual Analysis.

Motor deficits are widely documented among autistic individuals, and speech characteristics consistent with a motor speech disorder have been reported in prior literature. We conducted an auditory-perceptual analysis of speech production skills in low and minimally verbal autistic individuals as a step toward clarifying the nature of speech production impairments in this population and the potential link between oromotor functioning and language development. Fifty-four low or minimally verbal autistic individuals aged 4-18 years were video-recorded performing nonspeech oromotor tasks and producing phonemes, syllables, and words in imitation. Three trained speech-language pathologists provided auditory perceptual ratings of 11 speech features reflecting speech subsystem performance and overall speech production ability. The presence, attributes, and severity of signs of oromotor dysfunction were analyzed, as were relative performance on nonspeech and speech tasks and correlations between perceptual speech features and language skills. Our findings provide evidence of a motor speech disorder in this population, characterized by perceptual speech features including reduced intelligibility, decreased consonant and vowel precision, and impairments of speech coordination and consistency. Speech deficits were more associated with articulation than with other speech subsystems. Speech production was more impaired than nonspeech oromotor abilities in a subgroup of the sample. Oromotor deficits were significantly associated with expressive and receptive language skills. Findings are interpreted in the context of known characteristics of the pediatric motor speech disorders childhood apraxia of speech and childhood dysarthria. These results, if replicated in future studies, have significant potential to improve the early detection of language impairments, inform the development of speech and language interventions, and aid in the identification of neurobiological mechanisms influencing communication development.

Dynamic Temporal and Tactile Cueing in Young Children With Childhood Apraxia of Speech: A Multiple Single-Case Design.

Childhood apraxia of speech (CAS) is a multivariate motor speech disorder that requires a motor-based intervention approach. There is limited treatment research on young children with CAS, reflecting a critical gap in the literature given that features of CAS are often in full expression early in development. Dynamic Temporal and Tactile Cueing (DTTC) is a treatment approach designed for children with severe CAS, yet the use of DTTC with children younger than 3 years of age has not been examined. A multiple single-case design was employed to examine the use of DTTC in seven children with CAS (aged 2.5-5 years) over the course of 6 weeks of intervention. Changes in word accuracy were measured in treated words from baseline to posttreatment and from baseline to maintenance (6 weeks posttreatment). Generalization of word accuracy changes to matched untreated words was also examined. A linear mixed-effects model was used to estimate the change in word accuracy for treated and untreated words across all children from baseline to posttreatment and to maintenance. A quasi-Poisson regression model was used to estimate mean change and calculate effect sizes for treated and untreated words. Group-level analyses revealed significant changes in word accuracy for treated and untreated words at posttreatment and maintenance. At the child level, six of seven children displayed medium-to-large effect sizes where word accuracy increased in an average of 3.4/5 words across all children. Each child displayed some degree of generalization to untreated targets, specifically for words with the same syllable shape as the treated words. These results demonstrate that DTTC can yield positive change in some young children with CAS. Key differences in each child's performance are highlighted.

Oral Motor Disorders And Speech Disorders As Risk Factors For Difficulty Eating In Children Aged 6-60 Months

Oral Motor Disorders And Speech Disorders As Risk Factors For Difficulty Eating In Children Aged 6-60 Months

Characterizing Speech Errors Across Primary Progressive Apraxia of Speech Subtypes.

Apraxia of speech (AOS) is a motor speech disorder affecting articulatory planning and speech programming. When AOS is the sole manifestation of neurodegeneration, it is termed primary progressive apraxia of speech (PPAOS). Recent work has shown that there are distinct PPAOS subtypes: phonetic, prosodic, and those that do not clearly align with either (mixed). PPAOS subtypes differ with respect to the predominating motor speech difficulties, as well as disease progression and underlying pathology. Because past studies have determined PPAOS subtype based on clinical impression, the goal of the present study was to quantitatively determine the distribution of speech error types across PPAOS subtypes in a word repetition task and to investigate how word complexity affects the type and number of speech errors across PPAOS subtypes. Forty-five patients with PPAOS (13 phonetic, 23 prosodic, and nine mixed) and 45 healthy controls produced multiple repetitions of words that varied in phonetic complexity. Sound additions, deletions, and substitutions/distortions (phonetic errors) and within-word segmentations (prosodic errors) were calculated. All three PPAOS groups produced significantly more errors than controls, but the total number of errors was comparable among subtypes. The phonetic group produced more phonetic-type errors compared to the prosodic group but comparable to the mixed group. The prosodic group produced more segmentations compared to the phonetic and mixed PPAOS groups. As word complexity increased, the total number of errors increased for PPAOS patients. The phonetic and prosodic groups were more likely to produce phonetic- and prosodic-type errors, respectively, as word complexity increased. This study provides novel quantitative data showing that PPAOS subtype can be supported by the type and distribution of speech errors in a word repetition task. This may facilitate earlier, more reliable differential diagnosis and aid in disease prognosis, as PPAOS subtypes have distinct disease trajectories.

Speech Science as the Foundation for Voice and Motor Speech Disorders

Purpose: Physiological concepts can be effectively taught in speech science. These will serve as the foundation for understanding the physiological changes associated with neurogenic and voice disorders. In this tutorial, relevant concepts are highlighted across the respiratory, phonatory, velopharyngeal, and articulatory systems. Student activities and illustrative videos are presented. The culminating activity is based on a speech sample of an individual with moderate flaccid–spastic dysarthria. Students relate the physiological changes associated with dysarthria to the acoustic outcomes. Conclusions: Although traditionally speech science focuses on acoustics, this tutorial provides guidance on shaping the class to highlight the physiology underlying the acoustics. In this manner, students more easily see the clinical relevance.

Anticipatory coarticulation of the Spanish alveolar fricative /s/ in adults with apraxia versus dysarthria

This acoustic study compares anticipatory coarticulation characteristics of the Spanish alveolar sibilant fricative /s/ when in utterance-initial position followed by a vowel in adults with dysarthria and apraxia of speech. Three groups of participants (28 individuals with no speech disorder, 20 with dysarthria, and 8 with apraxia of speech) produced 12 monosyllabic words that included the five vowel sounds of central-peninsular Spanish. The acoustic measurements compared within and between groups were frequency of the spectral intensity peak (FreqMid) in different zones of fricative execution, magnitude of the change in frequency of the spectral intensity peak (ΔFreq) in the end zone compared to the average of the initial and middle zones, first three spectral moments, and the difference in spectral center of gravity between the middle and end zones (DiffM-E CoG). Several of these measures were able to differentiate between dysarthric and healthy speech, especially when /s/ was followed by an unrounded vowel, and the same occurred for apraxia, but this time when the adjacent vowel was rounded. While both disorders showed similar spectral patterns, the two motor speech disorders differed in terms of the measures FreqMid and DiffM-E CoG. Possible explanations for these differences are here discussed within the framework of motor control models.

Efficacy and feasibility of a digital speech therapy for post-stroke dysarthria: protocol for a randomized controlled trial.

Dysarthria is a motor speech disorder caused by various neurological diseases, particularly stroke. Individuals with post-stroke dysarthria experience impaired speech intelligibility, communication difficulties, and a reduced quality of life. However, studies on the treatment of post-stroke dysarthria are lacking. Digital speech therapy applications have the advantages of being personalized and easily accessible. However, evidence for their efficacy is not rigorous. Moreover, no studies have investigated both the acute to subacute, and chronic phases of stroke. This study aims to investigate the efficacy and feasibility of digital speech therapy applications in addressing these gaps in dysarthria treatment. This study is a multicenter, prospective, randomized, evaluator-blinded non-inferiority trial. We aim to recruit 76 participants with post-stroke dysarthria. Eligible participants will be stratified based on the onset period of stroke into acute to subacute, and chronic phases. Participants will be randomized in a 1:1 to receive either a personalized digital speech therapy application or conventional therapy with a workbook for 60 min daily, 5 days a week, for 4 weeks. The primary outcome is the improvement in speech intelligibility. This will be measured by how accurately independent listeners can transcribe passages read by the participants. Secondary outcomes, which include speech function, will be evaluated remotely by speech-language pathologists. This includes the maximum phonation time, oral diadochokinetic rate, and percentage of consonants correct. Participants' psychological well-being will also be assessed using self-report questionnaires, such as depressive symptoms (Patient Health Questionnaire-9) and quality of life (Quality of Life in the Dysarthric Speaker scale). The trial will also assess the feasibility, participant adherence, and usability of the application. Rigorous data collection and monitoring will be implemented to ensure patient safety. This trial aims to investigate the efficacy and feasibility of digital speech therapy applications for treating post-stroke dysarthria. The results could establish foundational evidence for future clinical trials with larger sample sizes. Clinicaltrials.gov, identifier: NCT05865106.

Acupuncture for ischemic stroke: Where are we now?

Acupuncture is an effective treatment for ischemic stroke (IS) and plays a key role in neurological rehabilitation after IS. Acupuncture can improve the clinical symptoms of various complications after IS, including motor dysfunction, swallowing disorders, speech disorders, cognitive impairment, depression, insomnia, and fatigue. However, the mechanisms underlying the effects of acupuncture in IS remain unclear. Available evidence suggests that acupuncture may exert neuroprotective effects through neuroplasticity (neurogenesis and synaptogenesis), angiogenesis, cell proliferation and apoptosis, and regulation of oxidative stress, inflammation, and immunity. Further studies should be conducted to improve the high-quality evidence-based system of acupuncture intervention for IS, by focusing on the clinical and basic research design, increasing the sample size, standardizing and quantifying the standards of acupuncture operations, using multidisciplinary techniques and methods to systematically explore the key targets of acupuncture intervention for IS, and reveal the efficacy and mechanism of acupuncture in the treatment of IS.

Dialect identification, intelligibility ratings, and acceptability ratings of dysarthric speech in two American English dialects

ABSTRACT The current study explored the intelligibility and acceptability ratings of dysarthric speakers with African American English (AAE) and General American English (GAE) dialects by listeners who identify as GAE or AAE speakers, as well as listener ability to identify dialect in dysarthric speech. Eighty-six listeners rated the intelligibility and acceptability of sentences extracted from a passage read by speakers with dysarthria. Samples were used from the Atlanta Motor Speech Disorders Corpus and ratings were collected via self-report. The listeners identified speaker dialect in a forced-choice format. Listeners self-reported their dialect and exposure to AAE. AAE dialect was accurately identified in 63.43% of the the opportunities; GAE dialect was accurately identified in 70.35% of the opportunities. Listeners identifying as AAE speakers rated GAE speech as more acceptable, whereas, listeners identifying as GAE speakers rated AAE speech as more acceptable. Neither group of listeners demonstrated a difference in intelligibility ratings. Exposure to AAE had no effect on intelligibility or acceptability ratings. Listeners can identify dialect (AAE and GAE) with a better than chance degree of accuracy. One’s dialect may have an effect on intelligibility and acceptability ratings. Exposure to a dialect did not affect listener ratings of intelligibility or acceptability.

Longitudinal flortaucipir, metabolism and volume differ between phonetic and prosodic speech apraxia.

Progressive apraxia of speech (PAOS) is a neurodegenerative motor-speech disorder that most commonly arises from a four-repeat tauopathy. Recent studies have established that progressive apraxia of speech is not a homogenous disease but rather there are distinct subtypes: the phonetic subtype is characterized by distorted sound substitutions, the prosodic subtype by slow and segmented speech and the mixed subtype by a combination of both but lack of predominance of either. There is some evidence that cross-sectional patterns of neurodegeneration differ across subtypes, although it is unknown whether longitudinal patterns of neurodegeneration differ. We examined longitudinal patterns of atrophy on MRI, hypometabolism on 18F-fluorodeoxyglucose-PET and tau uptake on flortaucipir-PET in a large cohort of subjects with PAOS that had been followed for many years. Ninety-one subjects with PAOS (51 phonetic, 40 prosodic) were recruited by the Neurodegenerative Research Group. Of these, 54 (27 phonetic, 27 prosodic) returned for annual follow-up, with up to seven longitudinal visits (total visits analysed = 217). Volumes, metabolism and flortaucipir uptake were measured for subcortical and cortical regions, for all scans. Bayesian hierarchical models were used to model longitudinal change across imaging modalities with PAOS subtypes being compared at baseline, 4 years from baseline, and in terms of rates of change. The phonetic group showed smaller volumes and worse metabolism in Broca's area and the striatum at baseline and after 4 years, and faster rates of change in these regions, compared with the prosodic group. There was also evidence of faster spread of hypometabolism and flortaucipir uptake into the temporal and parietal lobes in the phonetic group. In contrast, the prosodic group showed smaller cerebellar dentate, midbrain, substantia nigra and thalamus volumes at baseline and after 4 years, as well as faster rates of atrophy, than the phonetic group. Greater hypometabolism and flortaucipir uptake were also observed in the cerebellar dentate and substantia nigra in the prosodic group. Mixed findings were observed in the supplementary motor area and precentral cortex, with no clear differences observed across phonetic and prosodic groups. These findings support different patterns of disease spread in PAOS subtypes, with corticostriatal patterns in the phonetic subtype and brainstem and thalamic patterns in the prosodic subtype, providing insight into the pathophysiology and heterogeneity of PAOS.

Treatment approaches to Motor Speech Disorders: A step towards Evidence Based Practice.

Motor Speech Disorders is an umbrella term for a set of separate dysfunctions of speech outcome associated with neurological disorders. Motor speech disorders (MSD) are classified as Speech Motor delay (SMD), Childhood dysarthria (CD), Childhood Apraxia of Speech (CAS), and Concurrent CD and CAS. The incidence and prevalence of MSD in population is uncertain. A research gap exists, making evidence-based practice questionable as regards intervention for MSD and is an area of research. Hence, current narrative review was conducted to review and highlight treatment of MSD since evidence-based treatment approach may benefit patient even years after a brain lesion. To achieve this objective literature search was conducted using search engines and data bases including google, google scholar, web of science & PubMed from 1998 to 2023 with keywords "motor speech disorder, dysarthria, apraxia, speech motor delay and combinations of these words with English language and no other limitations. Our search revealed 170 articles, news, publications of which 34 were used for review (Fig.1).

Speed of Pitch Change in People with Parkinson’s Disease: A Pilot Study

Objective. To examine laryngeal maximum performance through a novel pitch diadochokinetic (DDK) task in people with Parkinson’s disease (PD) and healthy controls. Methods. This exploratory pilot study included a total of eight people with PD (seven male and one female) and eight healthy controls. Participants were instructed to rapidly transition or alternate between a chosen comfortable low and high pitch and were instructed to complete the task as a pitch glide. An Auditory Sawtooth Waveform Inspired Pitch Estimator-Prime model was used to first extract the pitch contour and then a customized MATLAB algorithm was used to compute and derive measures of pitch range and pitch slope. Results. Pitch range and slope were reduced in some participants with PD. Effects of age and disease duration were observed in people with PD: reductions in both pitch measures with increase in age and disease duration. Conclusions. A novel pitch DDK task may supplement the conventional laryngeal DDK task in the evaluation and treatment of motor speech and voice disorders. Individual variability analysis may provide specific diagnostic and therapeutic insights for people with PD.

Revisiting Dysarthria Treatment Across Languages: The Hybrid Approach.

Ten years after Miller and Lowit's (2014) groundbreaking book providing a cross-linguistic perspective on motor speech disorders, we ask where we are regarding dysarthria treatment across languages in two specific populations: adults with Parkinson's disease (PD) and children with cerebral palsy (CP). In this commentary, we consider preliminary evidence for both language-independent and language-specific approaches to treatment and propose a hybrid approach to speech treatment across languages, centered on the individual with dysarthria who speaks any given language. Treatment research on individuals with dysarthria secondary to PD and CP is advancing, but several areas remain to be explored. Next steps are suggested for addressing the paucity and complexity of cross-linguistic speech treatment research.

Improving Reliability of Magnetic Localization Using Input Space Transformation.

Body motion tracking for medical applications has the potential to improve quality of life for people with physical or speech motor disorders. Current solutions available in the market are either inaccurate, not affordable, or are impractical for a medical setting or at home. Magnetic localization can address these issues thanks to its high accuracy, simplicity of use, wearability, and use of inexpensive sensors such as magnetometers. However, sources of unreliability affect magnetometers to such an extent that the localization model trained in a controlled environment might exhibit poor tracking accuracy when deployed to end users. Traditional magnetic calibration methods, such as ellipsoid fit (EF), do not sufficiently attenuate the effect of these sources of unreliability to reach a positional accuracy that is both consistent and satisfactory for our target applications. To improve reliability, we developed a calibration method called post-deployment input space transformation (PDIST) that reduces the distribution shift in the magnetic measurements between model training and deployment. In this paper, we focused on change in magnetization or magnetometer as sources of unreliability. Our results show that PDIST performs better than EF in decreasing positional errors by a factor of ~3 when magnetization is distorted, and up to ~7 when our localization model is tested on a different magnetometer than the one it was trained with. Furthermore, PDIST is shown to perform reliably by providing consistent results across all our data collection that tested various combinations of the sources of unreliability.

Exploring digital speech biomarkers of hypokinetic dysarthria in a multilingual cohort

Hypokinetic dysarthria, a motor speech disorder characterized by reduced movement and control in the speech-related muscles, is mostly associated with Parkinson’s disease. Acoustic speech features thus offer the potential for early digital biomarkers to diagnose and monitor the progression of this disease. However, the influence of language on the successful classification of healthy and dysarthric speech remains crucial. This paper explores the analysis of acoustic speech features, both established and newly proposed, in a multilingual context to support the diagnosis of PD. The study aims to identify language-independent and highly discriminative digital speech biomarkers using statistical analysis and machine learning techniques. The study analyzes thirty-three acoustic features extracted from Czech, American, Israeli, Columbian, and Italian PD patients, as well as healthy controls. The analysis employs correlation and statistical tests, descriptive statistics, and the XGBoost classifier. Feature importances and Shapley values are used to provide explanations for the classification results. The study reveals that the most discriminative features, with reduced language dependence, are those measuring the prominence of the second formant, monopitch, and the frequency of pauses during text reading. Classification accuracies range from 67% to 85%, depending on the language. This paper introduces the concept of language robustness as a desirable quality in digital speech biomarkers, ensuring consistent behaviour across languages. By leveraging this concept and employing additional metrics, the study proposes several language-independent digital speech biomarkers with high discrimination power for diagnosing PD.

The PraxiFala Battery: A diagnostic accuracy study

Purpose To present the sensitivity and specificity and establish cutoff points (receiver operating characteristic [ROC] curve) for the PraxiFala Battery. Method The sample included 308 Brazilian-speaking children aged 3;0–7;11. Twenty-one children had motor speech disorders (MSD), 58 children had phonological disorder (PD), and 229 had typical speech (TS) development. Participants were administered the PraxiFala Battery, which contains verbal (word and sentence production), nonverbal (orofacial praxis), and diadochokinetic tasks. The sensitivity and specificity of items in each task were then calculated using ROC curves. Result Total scores on the verbal (word production), nonverbal (orofacial praxis), and diadochokinetic tasks had good sensitivity and specificity. The only scores with poor sensitivity and specificity in differentiating between TS, PD, and MSD were consistency and prosody in the verbal tasks (sentence production), and item /ta/ in the diadochokinetic task. Area under the ROC curve (AUC) values were greater than 0.7 for most items in the comparison between TS vs. MSD and PD vs. MSD. AUC values were poor or fair among children with TS and PD, suggesting that this instrument may not be accurate in identifying these groups. Conclusion The verbal, nonverbal, and diadochokinetic tasks in the PraxiFala Battery had good sensitivity and specificity.

The effect of real word stimuli versus non-word stimuli on oral diadochokinetic rates across the life span: An item discrimination analysis.

Diadochokinetic (DDK) rate tasks are extensively used in the evaluation of speech disorders; however, it is unclear how the different types of speech stimuli affect DDK rate performance. To investigate the effect of age, gender and type of stimuli (non-words versus real words) on the DDK rates in individuals across the lifespan and to provide normative data for Greek. Also to examine the discrimination ability of the speech DDK stimuli administered (non-words and real words) based on a dual DDK assessment protocol using a polytomous item response theory (IRT) model. The participants were 1747 monolingual Greek speakers (376 children, aged 4-17 years; and 1371 adults, aged 18-90+ years). All participants had normal hearing acuity which allowed them to understand and follow instructions. Participants with a medical condition or a language disorder which would affect DDK rate performance were excluded from the study. The time-by-count method was used, and all participants had to repeat as accurately and fast as possible: (1) four disyllabic non-words (/'gaba/, /'taka/, /'kata/, /'baga/), (2) four disyllabic real words (/'kapa/, /'tapa/, /ka'la/, /'paka/) and (3) two trisyllabic non-words (/'pataka/, /'badaga/). All responses were recorded and the speech samples that did not include at least 5 s of correct repetitions were excluded from the analysis. Age affected significantly DDK rates with performance increasing gradually until approximately the age of 40 and then gradually decreasing. Gender had no effect. Overall, there was a significant advantage of disyllabic real word stimuli over disyllabic non-word stimuli and of trisyllabic non-word stimuli over disyllabic non-word stimuli on DDK rates performance. IRT analysis suggested that the data fit the polytomous model reasonably well and all DDK stimuli (real words and non-words) showed a strong relationship (loadings > 0.50) with the latent trait. The current study complements prior research which supports that age and type of stimuli significantly affect DDK rates performance. It is the first study, that testifies to the benefit of real-word stimuli over non-word stimuli on DDK rates across the lifespan in a large representative sample. The implementation of IRT analysis provides empirical evidence about the discrimination ability of the DDK stimuli administered and confirms the reliability of this dual DDK assessment protocol. These findings are valuable for clinicians who work with motor speech disorders. What is already known on this subject Age, type of stimuli (real words versus non-words) and language significantly affect DDK rates performance. Current research strongly suggests the administration of language-specific norms since language-dependent features seem to have a noteworthy effect on the DDK rates, but scarce evidence exists about the discriminatory ability of the DDK speech stimuli commonly administered. What this study adds to the existing knowledge Conflicting findings have been reported about the effect of different types of DDK speech stimuli (real words and non-words) but no study to date has evaluated their discriminatory abilities. The current study is the first to implement a polytomous IRT model to examine this issue. This is also the first study to attempt an investigation of the effect of types of stimuli (real words versus non-words) on a large representative sample across the lifespan (4-90+ years) and to provide normative data for Greek. What are the practical and clinical implications of this work? The present study offers concrete evidence about the advantage of real-word stimuli over non-word stimuli in Greek, as well as normative data for the Greek-speaking populations. Moreover, the IRT analysis testifies to the discriminatory ability of real-word and non-word stimuli affirming the reliability of the present dual DDK assessment protocol as a psychometrically sound measure of DDK ability. The above has significant value for clinicians who work with individuals with motor speech disorders as the protocol can help them with the diagnosis and differential diagnosis of motor speech disorders.

Predictors of Functional Communication Outcomes in Children With Idiopathic Motor Speech Disorders.

The purpose of the study was to investigate child- and intervention-level factors that predict improvements in functional communication outcomes in children with motor-based speech sound disorders. Eighty-five preschool-age children with childhood apraxia of speech (n = 37) and speech motor delay (n = 48) participated. Multivariable logistic regression models estimated odds ratios and 95% confidence intervals for the association between minimal clinically important difference in the Focus on the Outcomes of Communication Under Six scores and multiple child-level (e.g., age, sex, speech intelligibility, Kaufman Speech Praxis Test diagnostic rating scale) and intervention-level predictors (dose frequency and home practice duration). Overall, 65% of participants demonstrated minimal clinically important difference changes in the functional communication outcomes. Kaufman Speech Praxis Test rating scale was significantly associated with higher odds of noticeable change in functional communication outcomes in children. There is some evidence that delivering the intervention for 2 times per week for 10 weeks provides benefit. A rating scale based on task complexity has the potential for serving as a screening tool to triage children for intervention from waitlist and/or determining service delivery for this population.

The impact of the Speech Systems Approach on intelligibility for children with cerebral palsy: a secondary analysis

Background The motor speech disorder, dysarthria, is common in cerebral palsy. The Speech Systems Approach therapy programme, which focuses on controlling breath supply and speech rate, has increased children’s intelligibility. Objective To ascertain if increased intelligibility is due to better differentiation of the articulation of individual consonants in words spoken in isolation and in connected speech. Design Secondary analysis. Setting University. Participants Forty-two children with cerebral palsy and dysarthria aged 5–18 years, Gross Motor Function Classification System I–V. Intervention The Speech Systems Approach is a motor learning therapy delivered to individuals by a speech and language therapist in 40-minute sessions, three times per week for 6 weeks. Intervention focuses on production of a strong, clear voice and speaking at a steady rate. Practice changes from single words to increasingly longer utterances in tasks with increasing cognitive load. Main outcome measures Unfamiliar listeners’ identification of singleton consonants (e.g. nap) and clusters of consonants (e.g. stair, end) at the start and end of words when hearing single words in forced choice tasks and connected speech in free transcription tasks. Acoustic measures of sound intensity and duration. Data sources Data collected at 1-week pre- and 1-week post-therapy from three studies: two interrupted time series design, one feasibility randomised controlled trial. Results Word initial and word final singleton consonants and consonant clusters were better identified post-therapy. The extent of improvement differed across word initial and word final singleton consonant subtypes. Improvement was greater for single words than connected speech. Change in sound identification varied across children, particularly in connected speech. Sound intensity and duration increases also were inconsistent. Limitations The small sample size did not allow for analysis of cerebral palsy type. Acoustic data were not available for all children, limiting the strength of conclusions that can be drawn. The different but phonetically balanced word lists, used in the original research, created variability in single words spoken across recordings analysed. Low frequencies of plosives, fricatives and affricates necessitated their combination for analysis preventing investigation of the effect of specific consonants. Connected speech was spontaneous, again creating variability within the data analysed. The estimated effects of therapy may therefore be partially explained by differences in the spoken language elicited. Conclusions The Speech Systems Approach helped children generate greater breath supply and a steady rate, leading to increased intensity and duration of consonant sounds in single words, thereby aiding their identification by listeners. Transfer of the motor behaviour to connected speech was inconsistent. Future work Refining the Speech Systems Approach to focus on connected speech early in the intervention. Personalisation of cues according to perceptual and acoustic speech measures. Creation of a battery of measures that can be repeated across children and multiple recordings. Study registration This trial is registered as Research Registry 6117. Funding This project was funded by the National Institute for Health and Care Research (NIHR) Efficacy and Mechanism Evaluation programme (NIHR130967) and will be published in full in Efficacy and Mechanism Evaluation; Vol. 10, No. 4. See the NIHR Journals Library website for further project information.