Lee Silverman voice treatment versus NHS speech and language therapy versus control for dysarthria in people with Parkinson's disease (PD COMM): pragmatic, UK based, multicentre, three arm, parallel group, unblinded, randomised controlled trial.

OBJECTIVES: To assess the clinical effectiveness of two speech and language therapy approaches versus no speech and language therapy for dysarthria in people with Parkinson's disease. DESIGN: Pragmatic, UK based, multicentre, three arm, parallel group, unblinded, randomised controlled trial. SETTING: The speech and language therapy interventions were delivered in outpatient or home settings between 26 September 2016 and 16 March 2020. PARTICIPANTS: 388 people with Parkinson's disease and dysarthria. INTERVENTIONS: Participants were randomly assigned to one of three groups (1:1:1): 130 to Lee Silverman voice treatment (LSVT LOUD), 129 to NHS speech and language therapy, and 129 to no speech and language therapy. LSVT LOUD consisted of four, face-to-face or remote, 50 min sessions each week delivered over four weeks. Home based practice activities were set for up to 5-10 mins daily on treatment days and 15 mins twice daily on non-treatment days. Dosage for the NHS speech and language therapy was determined by the local therapist in response to the participants' needs (estimated from prior research that NHS speech and language therapy participants would receive an average of one session per week over six to eight weeks). Local practices for NHS speech and language therapy were accepted, except for those within the LSVT LOUD protocol. Analyses were based on the intention to treat principle. MAIN OUTCOME MEASURES: The primary outcome was total score at three months of self-reported voice handicap index. RESULTS: People who received LSVT LOUD reported lower voice handicap index scores at three months after randomisation than those who did not receive speech and language therapy (-8.0 points (99% confidence interval -13.3 to -2.6); P<0.001). No evidence suggests a difference in voice handicap index scores between NHS speech and language therapy and no speech and language therapy (1.7 points (-3.8 to 7.1); P=0.43). Patients in the LSVT LOUD group also reported lower voice handicap index scores than did those randomised to NHS speech and language therapy (-9.6 points (-14.9 to -4.4); P<0.001). 93 adverse events (predominately vocal strain) were reported in the LSVT LOUD group, 46 in the NHS speech and language therapy group, and none in the no speech and language therapy group. No serious adverse events were recorded. CONCLUSIONS: LSVT LOUD was more effective at reducing the participant reported impact of voice problems than was no speech and language therapy and NHS speech and language therapy. NHS speech and language therapy showed no evidence of benefit compared with no speech and language therapy. TRIAL REGISTRATION: ISRCTN registry ISRCTN12421382.

Effects of SPEAK OUT! & LOUD Crowd on Functional Speech Measures in Parkinson's Disease.

PURPOSE: This study investigated the effects of the SPEAK OUT! & LOUD Crowd therapy program on speaking rate, percent pause time, intelligibility, naturalness, and communicative participation in individuals with Parkinson's disease (PD). METHOD: Six adults with PD completed 12 individual SPEAK OUT! sessions across four consecutive weeks followed by group-based LOUD Crowd sessions for five consecutive weeks. Most therapy sessions were conducted via telehealth, with two participants completing the SPEAK OUT! portion in person. Speech samples were recorded at six time points: three baseline time points prior to SPEAK OUT!, two post-SPEAK OUT! time points, and one post-LOUD Crowd time point. Acoustic measures of speaking rate and percent pause time and listener ratings of speech intelligibility and naturalness were obtained for each time point. Participant self-ratings of communicative participation were also collected at pre- and posttreatment time points. RESULTS: Results showed significant improvement in communicative participation scores at a group level following completion of the SPEAK OUT! & LOUD Crowd treatment program. Two participants showed a significant decrease in speaking rate and increase in percent pause time following treatment. Changes in intelligibility and naturalness were not statistically significant. CONCLUSIONS: These findings provide preliminary support for the effectiveness of the SPEAK OUT! & LOUD Crowd treatment program in improving communicative participation for people with mild-to-moderate hypokinetic dysarthria secondary to PD. This study is also the first to demonstrate positive effects of this treatment program for people receiving the therapy via telehealth.

Short-term effects of transcranial direct current stimulation on motor speech in Parkinson's disease: a pilot study.

INTRODUCTION: Hypokinetic dysarthria (HD) is a common motor speech symptom of Parkinson's disease (PD) which does not respond well to PD treatments. We investigated short-term effects of transcranial direct current stimulation (tDCS) on HD in PD using acoustic analysis of speech. Based on our previous studies we focused on stimulation of the right superior temporal gyrus (STG) - an auditory feedback area. METHODS: In 14 PD patients with HD, we applied anodal, cathodal and sham tDCS to the right STG using a cross-over design. A protocol consisting of speech tasks was performed prior to and immediately after each stimulation session. Linear mixed models were used for the evaluation of the effects of each stimulation condition on the relative change of acoustic parameters. We also performed a simulation of the mean electric field induced by tDCS. RESULTS: Linear mixed model showed a statistically significant effect of the stimulation condition on the relative change of median duration of silences longer than 50 ms (p = 0.015). The relative change after the anodal stimulation (mean = -5.9) was significantly lower as compared to the relative change after the sham stimulation (mean = 12.8), p = 0.014. We also found a correlation between the mean electric field magnitude in the right STG and improvement of articulation precision after anodal tDCS (R = 0.637; p = 0.019). CONCLUSIONS: The exploratory study showed that anodal tDCS applied over the auditory feedback area may lead to shorter pauses in a speech of PD patients.

Smartphone-Based Speech Therapy for Poststroke Dysarthria: Pilot Randomized Controlled Trial Evaluating Efficacy and Feasibility.

BACKGROUND: Dysarthria is a common poststroke speech disorder affecting communication and psychological well-being. Traditional speech therapy is effective but often poses challenges in terms of accessibility and patient adherence. Emerging smartphone-based therapies may offer promising alternatives for the treatment of poststroke dysarthria. OBJECTIVE: This study aimed to assess the efficacy and feasibility of smartphone-based speech therapy for improving speech intelligibility in patients with acute and early subacute poststroke dysarthria. This study also explored the impact of the intervention on psychological well-being, user experience, and overall feasibility in a clinical setting. METHODS: Participants were divided into 2 groups for this randomized, evaluator-blinded trial. The intervention group used a smartphone-based speech therapy app for 1 hour per day, 5 days per week, for 4 weeks, with guideline-based standard stroke care. The control group received standard guideline-based stroke care and rehabilitation. Speech intelligibility, psychological well-being, quality of life, and user acceptance were assessed using repeated measures ANOVA. RESULTS: In this study, 40 patients with poststroke dysarthria were enrolled, 32 of whom completed the trial (16 in each group). The intervention group showed significant improvements in speech intelligibility compared with the control group. This was evidenced by improvements from baseline (F1,30=34.35; P<.001), between-group differences (F1,30=6.18; P=.02), and notable time-by-group interactions (F1,30=6.91; P=.01). Regarding secondary outcomes, the intervention led to improvements in the percentage of correct consonants over time (F1,30=5.57; P=.03). In addition, significant reductions were noted in the severity of dysarthria in the intervention group over time (F1,30=21.18; P<.001), with a pronounced group effect (F1,30=5.52; P=.03) and time-by-group interaction (F1,30=5.29; P=.03). Regarding quality of life, significant improvements were observed as measured by the EQ-5D-3L questionnaire (F1,30=13.25; P<.001) and EQ-VAS (F1,30=7.74; P=.009) over time. The adherence rate to the smartphone-based app was 64%, with over half of the participants completing all the sessions. The usability of the app was rated high (system usability score 80.78). In addition, the intervention group reported increased self-efficacy in using the app compared with the control group (F1,30=10.81; P=.003). CONCLUSIONS: The smartphone-based speech therapy app significantly improved speech intelligibility, articulation, and quality of life in patients with poststroke dysarthria. These findings indicate that smartphone-based speech therapy can be a useful assistant device in the management of poststroke dysarthria, particularly in the acute and early subacute stroke stages. TRIAL REGISTRATION: ClinicalTrials.gov NCT05146765; https://clinicaltrials.gov/ct2/show/NCT05146765.

Clinical Insights Into the Use of Speech Amplification Devices for Managing Hypophonia: Interviews With Speech-Language Pathologists.

PURPOSE: The purpose of this qualitative interview study was to identify themes regarding considerations in the usage of speech amplification device usage for people with Parkinson's disease (PD) and hypophonia from the perspective of speech-language pathologists (SLPs). METHOD: Eligible participants included SLPs currently practicing in the United States or Canada with experience working with clients with PD for at least 2 years. Ten SLPs participated in 60-min interviews conducted via Zoom. A semistructured interview guide was created prior to the interviews. The interviews were transcribed following their completion, and an iterative coding process was used to identify themes using thematic analysis. RESULTS: Three main themes were identified from the interviews. The first theme encapsulated how clinicians described amplification devices as a potential treatment tool, which highlighted the nuances that may impact selecting an amplification device as a treatment option such as increased hypophonia or dysarthria severity and cognitive decline. The second theme highlighted how device selection depends on the individual needs of the user. Individual client characteristics (such as disease symptoms and individual needs and preferences) may impact the choice of amplification device. The last theme outlined the importance of involving family members in all stages of device use and involving other health care team members on a case-by-case basis. CONCLUSIONS: The insights provided by the SLP participants help to understand the clinical decisions that are made when determining device candidacy, selecting a device, and evaluating device success. These insights can be used to improve research studies of augmentative management of hypophonia and guide more personalized management decisions.

The Use of the Voice Trainer App for Vocal Control in People with a Degenerative Ataxia: A Pilot Intervention Study.

Dysarthria is disabling in persons with degenerative ataxia. There is limited evidence for speech therapy interventions. In this pilot study, we used the Voice trainer app, which was originally developed for patients with Parkinson's disease, as a feedback tool for vocal control. We hypothesized that patients with ataxic dysarthria would benefit from the Voice trainer app to better control their loudness and pitch, resulting in a lower speaking rate and better intelligibility. This intervention study consisted of five therapy sessions of 30 min within 3 weeks using the principles of the Pitch Limiting Voice Treatment. Patients received real-time visual feedback on loudness and pitch during the exercises. Besides, they were encouraged to practice at home or to use the Voice trainer in daily life. We used observer-rated and patient-rated outcome measures. The primary outcome measure was intelligibility, as measured by the Dutch sentence intelligibility test. Twenty-one out of 25 included patients with degenerative ataxia completed the therapy. We found no statistically significant improvements in intelligibility (p = .56). However, after the intervention, patients were speaking slower (p = .03) and the pause durations were longer (p < .001). The patients were satisfied about using the app. At the group level, we found no evidence for an effect of the Voice trainer app on intelligibility in degenerative ataxia. Because of the heterogeneity of ataxic dysarthria, a more tailor-made rather than generic intervention seems warranted.

Behavioral Management of Respiratory/Phonatory Dysfunction for Dysarthria Associated With Neurodegenerative Disease: A Systematic Review.

PURPOSE: This systematic review represents an update to previous reviews of the literature addressing behavioral management of respiratory/phonatory dysfunction in individuals with dysarthria due to neurodegenerative disease. METHOD: Multiple electronic database searches and hand searches of prominent speech-language pathology journals were conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses standards. RESULTS: The search yielded 1,525 articles, from which 88 met inclusion criteria and were reviewed by two blinded co-investigators. A large range of therapeutic approaches have been added to the evidence base since the last review, including expiratory muscle strength training, singing, and computer- and device-driven programs, as well as a variety of treatment modalities, including teletherapy. Evidence for treatment in several different population groups-including cerebellar ataxia, myotonic dystrophy, autosomal recessive spastic ataxia of Charlevoix-Saguenay, Huntington's disease, multiple system atrophy, and Lewy body dementia-were added to the current review. Synthesis of evidence quality provided strong evidence in support of only one behavioral intervention: Lee Silverman Voice Treatment Program (LSVT LOUD) in people with Parkinson's disease. No other treatment approach or population included in this review demonstrated more than limited evidence, reflecting that these approaches/populations require urgent further examination. CONCLUSION: Suggestions about where future research efforts could be significantly strengthened and how clinicians can apply research findings to their practice are provided. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.24964473.

Best practice recommendations for speech-language pathology in children with neuromuscular disorders: A Delphi-based consensus study.

PURPOSE: Speech-language pathology (SLP) is considered an essential intervention due to the high prevalence of dysphagia and dysarthria in paediatric neuromuscular disorders (pNMD). Evidence-based guidelines for SLP in pNMD are missing and children could be deprived the best of care. This study aimed to achieve consensus and present best practice recommendations on SLP intervention in pNMD. METHOD: A modified Delphi technique was used with a panel of experienced Dutch speech-language pathologists. In two online survey rounds and a face-to-face consensus meeting, the SLP experts proposed intervention items for cases of four types of pNMD (congenital myopathy, Duchenne muscular dystrophy, myotonic dystrophy type 1, and spinal muscular atrophy type 2), covering symptoms of dysphagia, dysarthria, drooling, and oral hygiene problems. They rated the level of agreement. RESULT: Intervention items that achieved consensus were incorporated into best practice recommendations. These recommendations cover six core intervention components (wait and see, explanation and advice, training and treatment, aids and adjustments, referral to other disciplines, and monitoring) suitable for the described symptoms. CONCLUSION: Insight into treatment options is essential to facilitate speech-language pathologists in clinical decision-making. The current study led to best practice recommendations for speech-language pathologists working within the field of pNMD.

Speech and language therapists' management practices, perceived effectiveness of current treatments and interest in neuromuscular electrical stimulation for acquired dysarthria rehabilitation: An international perspective.

BACKGROUND: Research is beginning to shed light on the practices employed by speech-language therapists (SLTs) for the management of acquired dysarthria. However, studies that explore SLTs' satisfaction with the effectiveness of current therapies and their interest in new treatment methods for this population have not been carried out. One potential new method is neuromuscular electrical stimulation (NMES): the pool of evidence for its use in rehabilitation is increasing, yet it has not been widely explored for use with dysarthria. AIM: To extend the understanding of acquired dysarthria management practices employed by SLTs across the globe and determine their satisfaction with current therapy options. To explore their interest in using NMES with this population. METHODS AND PROCEDURES: A cross-sectional international online survey was developed and disseminated to SLTs working with adults with acquired dysarthria through international professional associations. The survey collected information on demographic characteristics, dysarthria management practices, satisfaction with treatment effectiveness and interest in and knowledge of NMES. Survey responses were analysed using descriptive and inferential statistics, and quantitative content analysis. OUTCOMES AND RESULTS: A total of 211 SLTs (North America, 48.8%; Europe, 36%; Asia, 8.1%; Oceania, 5.7%; Africa, 0.9%; South America, 0.5%) completed the survey in full. Management practices varied considerably. There was a clear preference for informal assessments, mainly oral-motor examinations, focusing on body functions and structures. The majority of respondents rejected the use of non-speech oral motor exercises as a clinical or carryover exercise. Variable satisfaction with current speech subsystem treatments was noted; however, overall, there was a general dissatisfaction. Whilst a strong interest in the use of NMES for dysarthria was evidenced, it was noted that most SLTs lacked fundamental knowledge of NMES principles and application. CONCLUSION: SLTs' management practices and satisfaction with acquired dysarthria treatments differed substantially. Investigations of the potential use of NMES for dysarthria treatment are of interest. WHAT THIS PAPER ADDS: What is already known on the subject Recent country-specific surveys have explored speech-language therapists' (SLTs') assessment and intervention practices for acquired dysarthria. These studies indicate that although clinical management for this speech disorder mainly involves informal assessment tools and impairment-focused treatment, communication beyond the impairment, such as the activity and participation domains, is also frequently assessed and treated. What this paper adds to existing knowledge The majority of SLTs are dissatisfied with the overall benefits of current acquired dysarthria treatment. Phonatory, respiration and speech rate therapies are perceived to be more effective than prosody, articulation and resonance treatments. Despite a general lack of theoretical knowledge, most SLTs are interested in neuromuscular electrical stimulation treatment for acquired dysarthria. What are the potential or actual clinical implications of this work? New, evidence-based treatments are needed for SLTs to be confident in the effectiveness of their acquired dysarthria treatment.

Improving Perceptual Speech Ratings: The Effects of Auditory Training on Judgments of Dysarthric Speech.

PURPOSE: Auditory training has been shown to reduce rater variability in perceptual voice assessment. Because rater variability is also a central issue in the auditory-perceptual assessment of dysarthria, this study sought to determine if training produces a meaningful change in rater reliability, criterion validity, and scaling magnitude of four features: overall speech impairment, articulatory imprecision, monotony, and slow rate. METHOD: Forty-four nonexperts randomized to training and nontraining listener groups completed a pretest and posttest. Only the former group underwent auditory training between pre- and posttests. For both testing and training, listeners rated samples from speakers with amyotrophic lateral sclerosis (ALS), speakers with Parkinson's disease (PD), and neurologically healthy control speakers using separate visual analog scales (VASs) for each of the four features. Intraclass correlation coefficients were used to compare inter- and intrarater reliability between pre- and posttest for both listener groups. For criterion validity, severity ratings from the two nonexpert listener groups were compared to those of two experienced listeners for all four features. To determine changes in scaling magnitude, raw VAS scores for each feature were compared from pre- to posttest within the two nonexpert listener groups. Scaling changes were also compared between the two listener groups for the pre- and posttest conditions. RESULTS AND CONCLUSIONS: In the training group, a meaningful improvement in interrater reliability was observed for some features in all three speaker groups, but not in the nontraining group. In contrast, for intrarater reliability, in the nontraining group, a meaningful improvement was observed for many features in all three speaker groups, but only for PD monotony and slow rate in the training group. All ratings from the nonexpert listeners were valid except for monotony. Raw VAS scores did not meaningfully change from pre- to posttest for any of the features, but there was a trend toward lower scores posttraining, mainly for the ALS samples. Modifications to the auditory training paradigm to further improve reliability and validity, along with future goals for optimizing training, are discussed.

Clinical Assessment of Communication-Related Speech Parameters in Dysarthria: The Impact of Perceptual Adaptation.

PURPOSE: In current clinical practice, intelligibility of dysarthric speech is commonly assessed by speech-language therapists (SLTs), in most cases by the therapist caring for the patient being diagnosed. Since SLTs are familiar with dysarthria in general and with the speech of the individual patient to be assessed in particular, they have an adaptation advantage in understanding the patient's utterances. We examined whether and how listeners' assessments of communication-related speech parameters vary as a function of their familiarity with dysarthria in general and with the diagnosed patients in particular. METHOD: Intelligibility, speech naturalness, and perceived listener effort were assessed in 20 persons with dysarthria (PWD). Patients' speech samples were judged by the individual treating therapists, five dysarthria experts who were unfamiliar with the patients, and crowdsourced naïve listeners. Adaptation effects were analyzed using (a) linear mixed models of overall scoring levels, (b) regression models of severity dependence, (c) network analyses of between-listener and between-parameter relationships, and (d) measures of intra- and interobserver consistency. RESULTS: Significant advantages of dysarthria experts over laypeople were found in all parameters. An overall advantage of the treating therapists over nonfamiliar experts was only seen in listening effort. Severity-dependent adaptation effects occurred in all parameters. The therapists' responses were heterogeneous and inconsistent with those of the unfamiliar experts and the naïve listeners. CONCLUSIONS: The way SLTs evaluate communication-relevant speech parameters of the PWD whom they care for is influenced not only by adaptation benefits but also by therapeutic biases. This finding weakens the validity of assessments of communication-relevant speech parameters by the treating therapists themselves and encourages the development and use of alternative methods.

Effects of Conventional Speech Therapy with Liuzijue Qigong, a Traditional Chinese Method of Breath Training, in 70 Patients with Post-Stroke Spastic Dysarthria.

BACKGROUND Post-stroke spastic dysarthria (PSSD) is a motor speech impairment that impacts patient communication and quality of life. Liuzijue Qigong (LQG), a traditional Chinese method of breath training, could serve as an effective treatment for PSSD. This study compared the effects of conventional speech therapy and conventional speech therapy combined with LQG in patients with PSSD. MATERIAL AND METHODS Seventy patients with PSSD were randomly divided into a control group (conventional speech therapy, n=35, 77.14% cerebral infarction, 22.86% cerebral hemorrhage) and experimental group (LQG combined with conventional speech therapy, n=35, 85.71% cerebral infarction, 14.29% cerebral hemorrhage). Conventional speech therapy included relaxation, breath control, organ articulation, and pronunciation training. LQG involved producing 6 different sounds (Xu, He, Hu, Si, Chui, and Xi) accompanied by breathing and body movements. Patients were treated once a day, 5 times a week, for 4 weeks. The Frenchay Dysarthria Assessment scale (FDA), speech articulation, maximum phonation time (MPT), loudness, and Montreal Cognitive Assessment scale (MoCA) were evaluated. RESULTS At 4 weeks, the experimental group showed significant improvements compared with the control group in the change of FDA (13.26±6.84 vs 18.03±5.32, P=0.028), speech articulation (63.17±22.40 vs 76.51±15.28, P=0.024), MPT (1.34±1.30 vs 3.89±3.98, P<0.001), loudness (3.46±2.74 vs 7.14±2.56, P=0.009), MoCA (19.40±3.72 vs 22.20±5.30, P=0.020), total effective rate (68.57% vs 88.57%, P=0.041). CONCLUSIONS LQG, when combined with conventional speech therapy, enhanced the comprehensive speech ability of patients with PSSD compared with conventional treatment alone.

Distinct phenotypes of stimulation-induced dysarthria represent different cortical networks in STN-DBS.

BACKGROUND: Deep brain stimulation of the subthalamic nucleus is an effective treatment of Parkinson's disease, yet it is often associated with a general deterioration of speech intelligibility. Clustering the phenotypes of dysarthria has been proposed as a strategy to tackle these stimulation-induced speech problems. METHODS: In this study, we examine a cohort of 24 patients to test the real-life application of the proposed clustering and attempt to attribute the clusters to specific brain networks with two different approaches of connectivity analysis. RESULTS: Both our data-driven and hypothesis-driven approaches revealed strong connections of variants of stimulation-induced dysarthria to brain regions that are known actors of motor speech control. We showed a strong connection between the spastic dysarthria type and the precentral gyrus and supplementary motor area, prompting a possible disruption of corticobulbar fibers. The connection between the strained voice dysarthria and more frontal areas hints toward a deeper disruption of the motor programming of speech production. CONCLUSIONS: These results provide insights into the mechanism of stimulation-induced dysarthria in deep brain stimulation of the subthalamic nucleus and may guide reprogramming attempts for individual Parkinson's patients based on pathophysiological understanding of the affected networks.

The Application of Time-Frequency Masking To Improve Intelligibility of Dysarthric Speech in Background Noise.

PURPOSE: Background noise reduces speech intelligibility. Time-frequency (T-F) masking is an established signal processing technique that improves intelligibility of neurotypical speech in background noise. Here, we investigated a novel application of T-F masking, assessing its potential to improve intelligibility of neurologically degraded speech in background noise. METHOD: Listener participants (N = 422) completed an intelligibility task either in the laboratory or online, listening to and transcribing audio recordings of neurotypical (control) and neurologically degraded (dysarthria) speech under three different processing types: speech in quiet (quiet), speech mixed with cafeteria noise (noise), and speech mixed with cafeteria noise and then subsequently processed by an ideal quantized mask (IQM) to remove the noise. RESULTS: We observed significant reductions in intelligibility of dysarthric speech, even at highly favorable signal-to-noise ratios (+11 to +23 dB) that did not impact neurotypical speech. We also observed significant intelligibility improvements from speech in noise to IQM-processed speech for both control and dysarthric speech across a wide range of noise levels. Furthermore, the overall benefit of IQM processing for dysarthric speech was comparable with that of the control speech in background noise, as was the intelligibility data collected in the laboratory versus online. CONCLUSIONS: This study demonstrates proof of concept, validating the application of T-F masks to a neurologically degraded speech signal. Given that intelligibility challenges greatly impact communication, and thus the lives of people with dysarthria and their communication partners, the development of clinical tools to enhance intelligibility in this clinical population is critical.

The Effects of Deep Brain Stimulation on Speech Motor Control in People With Parkinson's Disease.

PURPOSE: Despite the overall benefits of deep brain stimulation (DBS) in Parkinson's disease (PD), its effects on speech production have been mixed when examined using auditory-perceptual and acoustic measures. This study investigated the effects of DBS on the lip and jaw kinematics during sentence production in individuals with dysarthria secondary to PD. METHOD: Twenty-seven participants from three groups were included in the study: (a) individuals with PD and without DBS (PD group), (b) individuals with PD and with DBS (PD-DBS group), and (c) neurologically healthy control speakers (HC group). Lip and jaw movements during speech were recorded using optical motion capture and analyzed for path distance, speed, duration, articulatory stability, and interarticulator coordination. RESULTS: The PD-DBS group showed (a) increased path distance compared with the PD and HC groups and (b) increased speed compared with the PD group but not the HC group. Both PD and PD-DBS groups exhibited lengthened sentence duration compared with the HC group. Articulatory stability was greater for the two PD groups, PD and PD-DBS, compared with the HC group. Spatial, but not temporal, coordination was lower for the PD group than for the other two groups. The only kinematic changes between the DBS on and off conditions within the PD-DBS group were increases in spatial coordination. CONCLUSIONS: These data suggest that DBS primarily affects the amplitude scaling of articulatory movements, but not the temporal scaling, in individuals with PD. The findings are discussed with respect to the DBS-induced neural changes and their effects on speech motor control in PD.

Lateral cerebellothalamic tract activation underlies DBS therapy for Essential Tremor.

BACKGROUND: While deep brain stimulation (DBS) therapy can be effective at suppressing tremor in individuals with medication-refractory Essential Tremor, patient outcome variability remains a significant challenge across centers. Proximity of active electrodes to the cerebellothalamic tract (CTT) is likely important in suppressing tremor, but how tremor control and side effects relate to targeting parcellations within the CTT and other pathways in and around the ventral intermediate (VIM) nucleus of thalamus remain unclear. METHODS: Using ultra-high field (7T) MRI, we developed high-dimensional, subject-specific pathway activation models for 23 directional DBS leads. Modeled pathway activations were compared with post-hoc analysis of clinician-optimized DBS settings, paresthesia thresholds, and dysarthria thresholds. Mixed-effect models were utilized to determine how the six parcellated regions of the CTT and how six other pathways in and around the VIM contributed to tremor suppression and induction of side effects. RESULTS: The lateral portion of the CTT had the highest activation at clinical settings (p < 0.05) and a significant effect on tremor suppression (p < 0.001). Activation of the medial lemniscus and posterior-medial CTT was significantly associated with severity of paresthesias (p < 0.001). Activation of the anterior-medial CTT had a significant association with dysarthria (p < 0.05). CONCLUSIONS: This study provides a detailed understanding of the fiber pathways responsible for therapy and side effects of DBS for Essential Tremor, and suggests a model-based programming approach will enable more selective activation of lateral fibers within the CTT.

Motor Speech Interventions for Children With Cerebral Palsy: A Systematic Review.

PURPOSE: Dysarthria is common among children with cerebral palsy (CP) and results in poor speech intelligibility and subsequently low communicative participation. Neuroplasticity evidence suggests that adherence to principles of motor learning (PML) improves motor speech intervention outcomes. Motor speech interventions aim to improve speech intelligibility and ultimately facilitate participation, but the effectiveness of these interventions and their inclusion of PML are not clear. Aims are as follows: (a) evaluate the effectiveness motor speech interventions in improving speech intelligibility; (b) summarize the aims, outcome measures, and outcomes relating to the International Classification of Functioning and Disability Child and Youth; and (c) summarize the principles of motor learning used in the intervention. METHOD: Eight databases were searched, complemented by a hand search. Studies of any level of evidence were included if they used a motor speech intervention and measured speech in children with CP aged 0-18 years. Studies before 2000 or not in English were excluded. The review was conducted and reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Study quality was rated using the Single Case Experimental Design Scale and Physiotherapy Evidence Database-P rating scales. The strength of evidence was evaluated with Grading of Recommendations, Assessment, Development and Evaluation. RESULTS: Of 1,036 initial articles, 21 were included. Eight interventions were identified including 131 participants aged 3-18 years. All studies aimed to improve speech intelligibility or articulation and reported improvement at sound, word, or sentence level. One study reported improvements in communicative participation. The strength of evidence ranged from very low to moderate for one intervention. Adherence to PML was inconsistent. CONCLUSIONS: The quality of evidence is very low to moderate. More research on motor speech interventions that adhere to PML is required. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.21817959.

COS-Speech: protocol to develop a core outcome set for dysarthria after stroke for use in clinical practice and research.

BACKGROUND: Dysarthria after stroke is when speech intelligibility is impaired, and this occurs in half of all stroke survivors. Dysarthria often leads to social isolation, poor psychological well-being and can prevent return to work and social lives. Currently, a variety of outcome measures are used in clinical research and practice when monitoring recovery for people who have dysarthria. When research studies use different measures, it is impossible to compare results from trials and delays our understanding of effective clinical treatments. The aim of this study is to develop a core outcome set (COS) to agree what aspects of speech recovery should be measured for dysarthria after stroke (COS-Speech) in research and clinical practice. METHODS: The COS-Speech study will include five steps: (1) development of a long list of possible outcome domains of speech that should be measured to guide the survey; (2) recruitment to the COS-Speech study of three key stakeholder groups in the UK and Australia: stroke survivors, communication researchers and speech and language therapists/pathologists; (3) two rounds of the Delphi survey process; (4) a consensus meeting to agree the speech outcomes to be measured and a follow-up consensus meeting to match existing instruments/measures (from parallel systematic review) to the agreed COS-Speech; (5) dissemination of COS-Speech. DISCUSSION: There is currently no COS for dysarthria after stroke for research trials or clinical practice. The findings from this research study will be a minimum COS, for use in all dysarthria research studies and clinical practice looking at post-stroke recovery of speech. These findings will be widely disseminated using professional and patient networks, research and clinical forums as well as using a variety of academic papers, videos, accessible writing such as blogs and links on social media. TRIAL REGISTRATION: COS-Speech is registered with the Core Outcome Measures in Effectiveness Trials (COMET) database, October 2021 https://www.comet-initiative.org/Studies/Details/1959 . In addition, "A systematic review of the psychometric properties and clinical utility of instruments measuring dysarthria after stroke" will inform the consensus meeting to match measures to COS-Speech. The protocol for the systematic reviews registered with the International Prospective Register of Systematic Reviews. PROSPERO registration number: CRD42022302998 .

Repetitive transcranial magnetic stimulation for hypokinetic dysarthria in Parkinson's disease enhances white matter integrity of the auditory-motor loop.

BACKGROUND AND PURPOSE: In our previous study, repeated sessions of repetitive transcranial magnetic stimulation (rTMS) over the auditory feedback area were shown to improve hypokinetic dysarthria (HD) in Parkinson's disease (PD) and led to changes in functional connectivity within the left-sided articulatory networks. We analyzed data from this previous study and assessed the effects of rTMS for HD in PD on the diffusion parameters of the left anterior arcuate fasciculus (AAF), which connects the auditory feedback area with motor regions involved in articulation. METHODS: Patients were assigned to 10 sessions of real or sham 1-Hz stimulation over the right posterior superior temporal gyrus. Stimulation effects were evaluated using magnetic resonance diffusion tensor imaging and by a speech therapist using a validated tool (Phonetics score of the Dysarthric Profile) at baseline, immediately after 2 weeks of stimulation, and at follow-up visits at Weeks 6 and 10 after the baseline. RESULTS: Altogether, data from 33 patients were analyzed. A linear mixed model revealed significant time-by-group interaction (p = 0.006) for the relative changes of fractional anisotropy of the AAF; the value increases were associated with the temporal evolution of the Phonetics score (R = 0.367, p = 0.028) in the real stimulation group. CONCLUSIONS: Real rTMS treatment for HD in PD as compared to sham stimulation led to increases of white matter integrity of the auditory-motor loop during the 2-month follow-up period. The changes were related to motor speech improvements.

An Efficacy Study of Voice Quality Using Cepstral Analyses of Phonation in Parkinson's Disease before and after SPEAK-OUT!®.

INTRODUCTION: SPEAK-OUT!® is a behavioral treatment for hypokinetic dysarthria in persons with Parkinson's disease (PD) that has become an alternative to the gold-standard Lee Silverman Voice Treatment (LSVT) in recent years. Acoustic evaluation of the efficacy of SPEAK-OUT!® therapy has focused on prosody. The purpose of this study was to investigate SPEAK-OUT!® efficacy in terms of vocal quality and its impact on quality of life. Vocal quality was measured acoustically using cepstral peak prominence (CPP) analysis and the Acoustic Voice Quality Index (AVQI) and perceptually using clinical ratings of speech performance. Impact on quality of life was measured with the Voice Handicap Index (VHI) and Voice-Related Quality of Life (V-RQOL). An additional goal of this study was to investigate whether dysarthria severity and disease duration were predictive of changes in voice quality due to SPEAK-OUT!®. METHODS: Pre- and post-therapy data included PD participants' acoustic and perceptual ratings of audio recordings. Demographic data included age, sex, diagnosis, duration of PD, and severity of dysarthria. RESULTS: Participants achieved significant improvement in the vowel and sentence CPP smoothed (CPPS) mean score as well as in their AVQI score post SPEAK-OUT!® treatment. Improvements in AVQI correlated negatively with disease duration and positively with dysarthria severity. DISCUSSION/CONCLUSION: SPEAK-OUT!® is effective in improving voice quality in patients with hypokinetic dysarthria due to idiopathic PD. Patients with more severe dysarthria and with a shorter disease duration may benefit the most, supporting earlier intervention. As for the type of measurement, AVQI combines acoustics from both vowel and sentence contexts and may therefore be the measure of choice over CPPS (vowel) or CPPS (sentence).