Motor Speech Disorders Research Articles

Progression of Motor Speech Function in Speakers With Primary Progressive Apraxia of Speech.

Speakers with primary progressive apraxia of speech (PPAOS) have an insidious onset of motor speech planning/programming difficulties. As the disease progresses, the apraxia of speech (AOS) becomes more severe and a co-occurring dysarthria often emerges. Here, longitudinal data from speakers with phonetic- and prosodic-predominant PPAOS are used to characterize the progression of their motor speech impairment, including the development of dysarthria and mutism. Data are presented from 52 speakers who had PPAOS at enrollment (i.e., progressive AOS in the absence of aphasia, cognitive, or other neurologic symptoms). Twenty-one had predominantly phonetic features, whereas 31 had primarily prosodic features. All participants underwent a comprehensive motor speech evaluation at their enrollment visit and each annual return visit, with a median of three visits per participant. Almost 25% of the speakers with PPAOS presented with dysarthria at their enrollment visit (median disease duration of 3.65 years), whereas more than 70% of them had developed dysarthria by their last visit (median disease duration of 6.85 years). Neither the likelihood to develop dysarthria nor the disease duration at which it was detected differed significantly between the phonetic and prosodic groups. However, muteness emerged sooner for speakers with phonetic-predominant PPAOS; the median disease duration at which they became mute was 1.5 years shorter than for their prosodic counterparts. Clinically, these results facilitate more accurate prognostication of motor speech symptoms in speakers with PPAOS, allowing for timely introduction of alternative means of communication. The results also support the differentiation between progressive AOS and dysarthria as distinct motor speech disorders that often co-occur in these individuals.

Clinical and functional characteristics of co-occurring cerebral palsy and autism spectrum disorder among children and young adults

BackgroundTo examine clinical and functional factors associated with co-occurring cerebral palsy (CP) and autism spectrum disorder (ASD). MethodsData were collected from the electronic health records of 994 patients with CP aged 3 to 26 years (59 % males) who received services from a U.S. hospital system between January 1, 2016 and July 1, 2021. CP, ASD, and other co-occurring conditions were abstracted using International Classification of Diseases - 10th Revision (ICD-10) codes, diagnostic summaries, and clinical descriptions. Bivariate and adjusted multivariable analyses examined the association between ASD, CP type, Gross Motor Function Classification System (GMFCS) level, speech or language disorders, and mental or behavioral problems. ResultsPrevalence of ASD was 8.2 % among patients with CP. Patients with GMFCS levels III-V were less likely to have a diagnosis of ASD (adjusted odds ratio [AOR] = 0.21; 95 % confidence interval [CI], 0.11–0.41). However, speech or language disorders (AOR = 6.00; 95 % CI, 2.14–16.81) and mental or behavioral problems (AOR =8.79; 95 % CI, 4.99–15.49) were associated with significantly higher odds of ASD. ConclusionsChildren and young adults with co-occurring CP and ASD have higher prevalence of clinical and functional impairments compared with counterparts with CP without co-occurring ASD. Screening for both conditions is necessary because of the high prevalence of ASD in this population. It is also necessary to implement specialized assessment procedures to decrease the risk of misclassifying or overlooking ASD among children and young adults with CP.

Cyanotic heart defects in children: neurological aspects of the problem

Background. The goal is to justify the need to monitor neurodevelopment in children with congenital heart defects (CHD) and to study neurological disorders in patients under 3 years of age with cyanotic heart defects. Materials and methods. Modern research on the neurodevelopment of children with CHD were analyzed. Sixty-two patients with cyanotic heart defects who underwent examination and surgical treatment at the Center for Pediatric Cardiology and Cardiac Surgery of the Ministry of Health of Ukraine were studied. They are divided into 2 groups: group 1 are children with critical cyanotic CHD and group 2 — with non-critical cyanotic CHD. The control group consisted of 35 healthy patients. A neurological examination was performed using standardized neurological scales. Data processing was carried out using the Stata 12.1 licensed statistical package. Results. Neurodevelopmental disorders were diagnosed in 33 (53 %) of 62 children with cyanotic CHD: in group 1 — in 29 % of cases and in group 2 — in 24 %. These groups were statistically homogeneous in terms of gestational age (p = 0.492) and body weight at birth, with no significant difference from the control group. Older age is characterized mainly by delays in the stages of motor development (16 % in group 1 and 15 % in group 2) and speech disorders (7 % in group 1 and 3 % in group 2). Acute disorders of cerebral circulation (6 % in group 2) and the presence of epileptic seizures (up to 3 %) were characteristic of children under 1 year. Apgar score was lower in patients with critical cyanotic CHD with neurodevelopmental delay and a longer duration of artificial circulation during surgical treatment. Conclusions. 1. Neurological disorders were diagnosed in 53 % of patients with cyanotic heart defects: in 29 % with critical heart defects and 24 % with non-critical heart defects. 2. Older children are characterized mainly by delays in the stages of motor development and speech disorders. Behavioral disorders are more typical for children with non-critical CHD. Acute disorders of cerebral circulation and the presence of epileptic seizures were characteristic of children under 1 year of age. 3. The influence of body weight and gestational age on neurodevelopmental disorders is excluded. The severe state of children with neurodevelopmental delay at birth and an increase in the duration of artificial circulation during surgical treatment were found. 4. Interdisciplinary examination of patients with cyanotic heart defects, including examination by a pediatric neurologist, as well as a follow-up is necessary for timely referral to the next stages of rehabilitation.

Expanding the molecular landscape of childhood apraxia of speech: evidence from a single-center experience.

Childhood apraxia of speech (CAS) is a genetically heterogeneous pediatric motor speech disorder. The advent of whole exome sequencing (WES) and whole genome sequencing techniques has led to increased identification of pathogenic variants in CAS genes. In an as yet uncharacterized Italian cohort, we aimed both to identify new pathogenic gene variants associated with CAS, and to confirm the disease-related role of genes already reported by others. We also set out to refine the clinical and neurodevelopmental characterization of affected children, with the aim of identifying specific, gene-related phenotypes. In a single-center study aiming to explore the genetic etiology of CAS in a cohort of 69 Italian children, WES was performed in the families of the 34 children found to have no copy number variants. Each of these families had only one child affected by CAS. High-confidence (HC) gene variants were identified in 7/34 probands, in two of whom they affected KAT6A and CREBBP, thus confirming the involvement of these genes in speech impairment. The other probands carried variants in low-confidence (LC) genes, and 20 of these variants occurred in genes not previously reported as associated with CAS. UBA6, ZFHX4, and KAT6A genes were found to be more enriched in the CAS cohort compared to control individuals. Our results also showed that most HC genes are involved in epigenetic mechanisms and are expressed in brain regions linked to language acquisition processes. Our findings confirm a relatively high diagnostic yield in Italian patients.

Tipping the Scales: Indiscriminate Use of Interval Scales to Rate Diverse Dysarthric Features.

Error related to incorrect use of rating scales is problematic in the assessment and treatment of dysarthria. The main purpose of this project was to determine scale fit for cardinal speech features of hypokinetic dysarthria. A secondary aim was to determine rater reliability for the two different scales explored. Forty-three speakers with Parkinson's disease (PD) and 25 neurologically healthy control talkers were recorded reading sentences from the Speech Intelligibility Test. Twenty-two healthy female listeners used both an equal appearing interval (EAI) scale and a direct magnitude estimation (DME) scale to rate five perceptual speech features (i.e., overall speech severity, articulatory imprecision, reduced loudness, short rushes of speech, and monotony) from these recordings. Regression analyses were used to determine the linearity of the relationship between the means of the EAI and DME ratings. Inter- and intrarater reliability was calculated using intraclass correlation coefficients and Spearman's correlation coefficients, respectively, for both EAI and DME ratings. There was a linear relationship between EAI and DME means for monotony, indicating it is a metathetic dimension. Curvilinear relationships were observed between the EAI and DME means for the other four features, indicating prothetic dimensions. Intra- and interrater reliability values were similar for EAI and DME ratings. Overall, results of this work suggest that DME is the best fit for scaling several hypokinetic dysarthria features, and not the conventionally used EAI scale. Prothetic dimensions best scaled by DME include overall speech severity, articulatory imprecision, reduced loudness, and short rushes of speech. Monotony was the only feature found to be a metathetic dimension and would be best scaled using EAI or DME. Findings call for rethinking the widespread use of EAI scales for rating perceptual features as part of the assessment and treatment of motor speech disorders.

Acquired motor speech disorders in childhood epilepsy.

To evaluate a group of children with epilepsy and motor speech regression, with the aim of characterizing their speech disorders, electrographic features, and outcomes. Children referred to a tertiary developmental epilepsy clinic with epilepsy and motor speech regression were identified retrospectively. A clinical history was taken, and longitudinal speech and cognitive data were recorded. Speech samples were scored for severity and speech features. Seizure frequency and epileptiform discharges in the interictal electroencephalogram were analysed. Eighteen children (10 female) were evaluated, including seven with Landau-Kleffner syndrome and six with Rasmussen syndrome. Speech regression occurred at a mean age of 5 years (SD = 2 years 6 months), which was concurrent with seizure onset or peak seizure burden in eight children. Speech features included dysarthria (n = 13), phonological errors (n = 7), and dyspraxia (n = 6). Electrographic abnormalities occurred most frequently in the left centrotemporal and right frontal regions. Among children who were followed up, intelligibility of speech was affected in 13 at baseline and seven at follow-up (p = 0.03). Expressive language standardized scores increased from a mean (SD) of 50.0 (11.3) to 91.4 (27.8) in children with Landau-Kleffner syndrome (mean change = 41.4, 95% confidence interval [CI] 0.04-82.8, p = 0.0498) and decreased from 75.2 (15.3) to 59.0 (9.8) in children with Rasmussen syndrome (mean change -16.2, 95% CI -9.0 to -23.4, p = 0.002) over the follow-up. Motor speech disorders in epilepsy were severe, multifarious, and often fluctuated with seizure burden. Symptoms typically improved, especially in children with Landau-Kleffner syndrome, but rarely fully resolved.

Introduction to the Forum: Native Language, Dialect, and Foreign Accent in Dysarthria.

This timely collection is an international effort to serve as a foundation to encourage research that offers insights into the interaction between language variation and motor speech disorders. Specifically, this forum aimed to provide a platform that (a) explores and demonstrates the role of language variation in the manifestation of dysarthria, (b) considers language variation in clinical assessment and management, and (c) promotes awareness of diverse language backgrounds of people with dysarthria. The forum contains six articles, spanning a variety of research designs (cross-sectional, pre- and post-treatment), kinds of articles (tutorial, research article, commentary), and a range of languages from around the world (English, French, Korean Portuguese, Spanish).

MED13L-related disorder characterized by severe motor speech impairment.

MED13L-related disorder is associated with intellectual disability, motor delay, and speech deficits. Previous studies have focused on broad clinical descriptions of individuals, but limited information regarding specific speech diagnoses and results of direct testing has been published to date. We conducted deep phenotyping to characterize the speech, language, motor, cognitive, and adaptive phenotypes of individuals with MED13L-related disorder. In this cross-sectional study, we administered standardized articulation, language, motor, and cognitive testing to 17 children and adolescents (mean age 9y 9m; SD 4y 5m; range 4y 2m to 19y 7m). In-person testing was supplemented with broad developmental, medical, and behavioral information collected virtually from a cohort of 67 individuals. All individuals who completed in-person articulation testing met diagnostic criteria for speech apraxia, dysarthria, or both. Language impairment was present in all of the in-person cohort and almost all (97%) of the virtual cohort. Those who were able to complete motor testing demonstrated significant deficits in visual motor integration (mean 57.08, SD 9.26). Full scale IQs fell in the borderline to intellectual disability range, consistent with reported cognitive impairment in 97% of the virtual cohort. Notable medical features included hypotonia (83%), vision problems (72%), recurrent otitis media (58%), gastrointestinal problems (57%), and seizures (31%). MED13L-related disorder is characterized by a high rate of motor speech disorders that occur in the context of globally impaired motor, language, and cognitive skills. Children would benefit from intensive, individualized speech therapy and the early adoption of augmentative communication strategies.

Accurate synthesis of dysarthric Speech for ASR data augmentation

Dysarthria is a motor speech disorder often characterized by reduced speech intelligibility through slow, uncoordinated control of speech production muscles. Automatic Speech Recognition (ASR) systems can help dysarthric talkers communicate more effectively. However, robust dysarthria-specific ASR requires a significant amount of training speech, which is not readily available for dysarthric talkers.This paper presents a new dysarthric speech synthesis method for the purpose of ASR training data augmentation. Differences in prosodic and acoustic characteristics of dysarthric spontaneous speech at varying severity levels are important components for dysarthric speech modeling, synthesis, and augmentation. For dysarthric speech synthesis, a modified neural multi-talker TTS is implemented by adding a dysarthria severity level coefficient and a pause insertion model to synthesize dysarthric speech for varying severity levels.To evaluate the effectiveness for synthesis of training data for ASR, dysarthria-specific speech recognition was used. Results show that a DNNHMM model trained on additional synthetic dysarthric speech achieves relative Word Error Rate (WER) improvement of 12.2 % compared to the baseline, and that the addition of the severity level and pause insertion controls decrease WER by 6.5 %, showing the effectiveness of adding these parameters. Overall results on the TORGO database demonstrate that using dysarthric synthetic speech to increase the amount of dysarthric-patterned speech for training has significant impact on the dysarthric ASR systems. In addition, we have conducted a subjective evaluation to evaluate the dysarthricness and similarity of synthesized speech. Our subjective evaluation shows that the perceived dysarthricness of synthesized speech is similar to that of true dysarthric speech, especially for higher levels of dysarthria. Audio samples are available at https://mohammadelc.github.io/SpeechGroupUKY/

A habitually open mouth posture leads to less affect strength during joy in childhood

AimCompared with children without orofacial disorders, children with a habitual lack of mouth closure and mouth breathing show less frequent and reduced or absent facial expressions. The facial feedback hypothesis states that affective sensation is enhanced by mimic involvement. In this randomized cross-sectional study with and without orofacially disordered children, we investigated the effect of lack of mouth closure on the strength of emotions related to joy, sadness and fear in children. We aimed to determine whether kindergarten and primary school-age children with a lack of mouth closure are less emotionally involved.Materials and MethodWe used facial feedback as an indicator to measure affect intensity in children with and without orofacial disorders. For this purpose, we modified the experimental design of Strack et al. (Strack et al. in J Pers Soc Psychol 54:768–777, 1988), in which the subjects were asked to hold a pencil exclusively with their teeth (experimental group 1, “joy”), with their lips (experimental group 2, “sadness” and “fear”) or with their nondominant hand (control group). Instead of cartoons, ten medium-funny animal pictures were presented individually in a predefined order to be judged on a Likert scale. The allocation to the groups was implemented using a randomized procedure, independent of the diagnosis, age and sex of the children. The only exclusion criteria were the presence of surgical scars in the orofacial area and cerebral palsy.ResultsA total of 414 children aged 4 to 17 years were studied for facial feedback, with orofacial disorders such as open mouth posture, tongue thrust, myofunctional disorder, craniomandibular dysfunction (CMD) and speech motor disorders diagnosed in 223 subjects. The significance tests showed that in all age groups, children with orofacial disorders rated the joke content of the animal pictures significantly lower than did children without orofacial disorders (4- to 6-year-olds: p value = 0.01, T value = 2.33, confidence = 99%; 7- to 8-year-olds: p value = 0, T value = 4.98, 100% confidence; 9- to 17-year-olds: p value = 0, T value = 2.87, 100% confidence). This finding indicates that children with a lack of mouth closure and other orofacial disorders not only express less pleasure with the help of facial expressions but also feel less pleasure. Moreover, the experimental setup used in this work, which has been modified for children, can be used to test facial feedback in young subjects.ConclusionIn our study, we focused on the interplay between physical and emotional development in children. If left untreated, children with a lack of oral closure may not only show deviations in the orofacial area later on, but also in their emotionality. We endeavored to highlight the importance of treating children with orofacial disorders at an early age.

Automatic Speech Recognition in Primary Progressive Apraxia of Speech.

Transcribing disordered speech can be useful when diagnosing motor speech disorders such as primary progressive apraxia of speech (PPAOS), who have sound additions, deletions, and substitutions, or distortions and/or slow, segmented speech. Since transcribing speech can be a laborious process and requires an experienced listener, using automatic speech recognition (ASR) systems for diagnosis and treatment monitoring is appealing. This study evaluated the efficacy of a readily available ASR system (wav2vec 2.0) in transcribing speech of PPAOS patients to determine if the word error rate (WER) output by the ASR can differentiate between healthy speech and PPAOS and/or among its subtypes, whether WER correlates with AOS severity, and how the ASR's errors compare to those noted in manual transcriptions. Forty-five patients with PPAOS and 22 healthy controls were recorded repeating 13 words, 3 times each, which were transcribed manually and using wav2vec 2.0. The WER and phonetic and prosodic speech errors were compared between groups, and ASR results were compared against manual transcriptions. Mean overall WER was 0.88 for patients and 0.33 for controls. WER significantly correlated with AOS severity and accurately distinguished between patients and controls but not between AOS subtypes. The phonetic and prosodic errors from the ASR transcriptions were also unable to distinguish between subtypes, whereas errors calculated from human transcriptions were. There was poor agreement in the number of phonetic and prosodic errors between the ASR and human transcriptions. This study demonstrates that ASR can be useful in differentiating healthy from disordered speech and evaluating PPAOS severity but does not distinguish PPAOS subtypes. ASR transcriptions showed weak agreement with human transcriptions; thus, ASR may be a useful tool for the transcription of speech in PPAOS, but the research questions posed must be carefully considered within the context of its limitations. https://doi.org/10.23641/asha.26359417.

Increased vowel contrast and intelligibility in connected speech induced by sensorimotor adaptation.

Alterations to sensory feedback can drive robust adaptive changes to the production of consonants and vowels, but these changes often have no behavioral relevance or benefit to communication (e.g., making "head" more like "had"). This work aims to align the outcomes of adaptation with changes known to increase speech intelligibility - specifically, adaptations that increase the acoustic contrast between vowels in running speech. To this end, we implemented a vowel centralization feedback perturbation paradigm that pushes all vowels towards the center of vowel space, making them sound less distinct from one another. Speakers across the adult lifespan adapted to the centralization perturbation during sentence production, increasing the global acoustic contrast among vowels and the articulatory excursions for individual vowels. These changes persisted after the perturbation was removed, including after a silent delay, and showed robust transfer to words that were not present in the sentences. Control analyses demonstrated that these effects were unlikely to be due to explicit pronunciation strategies and occurred in the face of increasingly more rapid and less distinct production of familiar sentences. Finally, sentence transcription by crowd-sourced listeners showed that speakers' vowel contrast predicted their baseline intelligibility and that experimentally-induced increases in contrast predicted intelligibility gains. These findings establish the validity of a sensorimotor adaptation paradigm to implicitly increase vowel contrast and intelligibility in connected speech, an outcome that has the potential to enhance rehabilitation in individuals who present with a reduced vowel space due to motor speech disorders, such as the hypokinetic dysarthria associated with Parkinson's disease.

An automatic measure for speech intelligibility in dysarthrias-validation across multiple languages and neurological disorders.

Dysarthria, a motor speech disorder caused by muscle weakness or paralysis, severely impacts speech intelligibility and quality of life. The condition is prevalent in motor speech disorders such as Parkinson's disease (PD), atypical parkinsonism such as progressive supranuclear palsy (PSP), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS). Improving intelligibility is not only an outcome that matters to patients but can also play a critical role as an endpoint in clinical research and drug development. This study validates a digital measure for speech intelligibility, the ki: SB-M intelligibility score, across various motor speech disorders and languages following the Digital Medicine Society (DiMe) V3 framework. The study used four datasets: healthy controls (HCs) and patients with PD, HD, PSP, and ALS from Czech, Colombian, and German populations. Participants' speech intelligibility was assessed using the ki: SB-M intelligibility score, which is derived from automatic speech recognition (ASR) systems. Verification with inter-ASR reliability and temporal consistency, analytical validation with correlations to gold standard clinical dysarthria scores in each disease, and clinical validation with group comparisons between HCs and patients were performed. Verification showed good to excellent inter-rater reliability between ASR systems and fair to good consistency. Analytical validation revealed significant correlations between the SB-M intelligibility score and established clinical measures for speech impairments across all patient groups and languages. Clinical validation demonstrated significant differences in intelligibility scores between pathological groups and healthy controls, indicating the measure's discriminative capability. The ki: SB-M intelligibility score is a reliable, valid, and clinically relevant tool for assessing speech intelligibility in motor speech disorders. It holds promise for improving clinical trials through automated, objective, and scalable assessments. Future studies should explore its utility in monitoring disease progression and therapeutic efficacy as well as add data from further dysarthrias to the validation.

A Goal-Writing Framework for Motor-Based Intervention for Childhood Apraxia of Speech.

There are multiple frameworks for goal writing that are applicable to the practice of speech-language pathology. Motor-based speech disorders are a subset of speech sound disorders that are thought to require specific elements of intervention that are typically not addressed in the traditional frameworks used in the clinical setting. The purpose of this tutorial is to review general approaches of goal writing and suggest additional elements that may be used to improve the efficiency and effectiveness of treatment for childhood motor speech disorders, specifically childhood apraxia of speech (CAS). Existing models of goal writing were reviewed to ascertain elements common to most of these models. A basic framework was chosen and modified to include behaviors, conditions, and approaches to goal measurement tailored to the clinical needs of children with CAS. A resource for clinical decision making for children with CAS was developed to inform goal writing at the onset of treatment and adaptations that occur over the course of treatment. Case studies are presented to demonstrate how the presented framework can be applied to writing goals for motor-based treatment for two different children with CAS. Children with CAS require a specialized approach to intervention, which requires goals to reflect the unique clinical needs of this population. This tutorial offers resources that use the best available research evidence and current understanding of effective treatment practices for CAS to guide clinical decision making for motor-based intervention and goal writing. This tutorial is intended to guide treatment planning across varied settings to facilitate progress and optimize treatment outcomes for children with CAS.

Analysis of Melodic Intonation Therapy (MIT) on Speech Ability in Stroke Patients with Aphasia at Srondol Health Center

The Irreversible brain disorders that cause sequelae in the form of motor aphasia or speech disorders which are mostly clinical manifestations in post-stroke patients cause inability to move, speech problems, perspective, because there are problems with brain function. Melodic Intonation Therapy (MIT) is the development of music as a therapeutic medium to improve language skills that use musical elements (intonation and beats) as therapy to improve language skills for people with aphasia. The purpose of this study is to analyze Melodic Intonation Therapy (MIT) on Speech Ability in Stroke Patients With Aphasia with the research stage based on field research in the Srondol community who experienced Stroke with speech difficulties/Aphasia. This research method uses an experimental quasy with a pre-post test with control group design with a sample of 30 respondents with the results of speech development of aphasia patients, international publications, and guidelines for the management of Melodic Intonation Therapy (MIT) in Stroke Patients with Aphasia. Based on the results of the study, it was found that patients who experienced stroke of the families of stroke patients supported him because family support was very important to maintain and maximize physical and cognitive recovery.

Clinical and functional characteristics of children and young adults with cerebral palsy and co-occurring attention-deficit/hyperactivity disorder

BackgroundEmerging research shows that children and young adults (CYAs) with cerebral palsy (CP) are at higher risk for attention-deficit/hyperactivity disorder (ADHD). However, little is known about the clinical and functional characteristics of CYAs with these co-occurring disorders. AimTo estimate associations between a diagnosis of ADHD among CYAs with CP and clinical and functional characteristics. MethodsThis retrospective, cross-sectional study used data from the electronic health records of CYAs (aged 4–26 years) with CP (n = 1145). We used bivariate and multivariable analyses to estimate associations between an ADHD diagnosis, CP type, Gross Motor Function Classification System (GMFCS) level, speech or language disorder, and intellectual disability. Results18.1 % of CYAs with CP had a diagnosis of ADHD. CYAs with spastic-bilateral CP had lower odds of ADHD (adjusted odds ratio [AOR] = 0.58; 95 % confidence interval [CI], 0.35–0.96). Odds of having ADHD were significantly lower for those with GMFCS levels III-V (AOR = 0.10; 95 % CI, 0.06–0.15). ConclusionsOur study found that a diagnosis of ADHD among CYAs with CP was associated with greater clinical and functional impairments compared to counterparts without ADHD. Findings highlight the need to screen for both conditions because of the high comorbidity rates in this population.

Effects of attentional instructions on the behavioral and neural mechanisms of speech auditory feedback control

The present study investigated how instructions for paying attention to auditory feedback may affect speech error detection and sensorimotor control. Electroencephalography (EEG) and speech signals were recorded from 21 neurologically intact adult subjects while they produced the speech vowel sound /a/ and received randomized ±100 cents pitch-shift alterations in their real-time auditory feedback. Subjects were instructed to pay attention to their auditory feedback and press a button to indicate whether they detected a pitch-shift stimulus during trials. Data for this group was compared with 22 matched subjects who completed the same speech task under altered auditory feedback condition without attentional instructions. Results revealed a significantly smaller magnitude of speech compensations in the attentional-instruction vs. no-instruction group and a positive linear association between the magnitude of compensations and P2 event-related potential (ERP) amplitudes. In addition, we found that the amplitude of P2 ERP component was significantly larger in the attentional-instruction vs. no-instruction group. Source localization analysis showed that this effect was accounted for by significantly stronger neural activities in the right hemisphere insula, precentral gyrus, postcentral gyrus, transverse temporal gyrus, and superior temporal gyrus in the attentional-instruction group. These findings suggest that attentional instructions may enhance speech auditory feedback error detection, and subsequently improve sensorimotor control via generating more stable speech outputs (i.e., smaller compensations) in response to pitch-shift alterations. Our data are informative for advancing theoretical models and motivating targeted interventions with a focus on the role of attentional instructions for improving treatment outcomes in patients with motor speech disorders.

Psychedelics in developmental stuttering to modulate brain functioning: a new therapeutic perspective?

Developmental stuttering (DS) is a neurodevelopmental speech-motor disorder characterized by symptoms such as blocks, repetitions, and prolongations. Persistent DS often has a significant negative impact on quality of life, and interventions for it have limited efficacy. Herein, we briefly review existing research on the neurophysiological underpinnings of DS -specifically, brain metabolic and default mode/social-cognitive networks (DMN/SCN) anomalies- arguing that psychedelic compounds might be considered and investigated (e.g., in randomized clinical trials) for treatment of DS. The neural background of DS is likely to be heterogeneous, and some contribution from genetically determinants of metabolic deficiencies in the basal ganglia and speech-motor cortical regions are thought to play a role in appearance of DS symptoms, which possibly results in a cascade of events contributing to impairments in speech-motor execution. In persistent DS, the difficulties of speech are often linked to a series of associated aspects such as social anxiety and social avoidance. In this context, the SCN and DMN (also influencing a series of fronto-parietal, somato-motor, and attentional networks) may have a role in worsening dysfluencies. Interestingly, brain metabolism and SCN/DMN connectivity can be modified by psychedelics, which have been shown to improve clinical evidence of some psychiatric conditions (e.g., depression, post-traumatic stress disorder, etc.) associated with psychological constructs such as rumination and social anxiety, which also tend to be present in persistent DS. To date, while there have been no controlled trials on the effects of psychedelics in DS, anecdotal evidence suggests that these agents may have beneficial effects on stuttering and its associated characteristics. We suggest that psychedelics warrant investigation in DS.

The encoding of speech modes in motor speech disorders: whispered versus normal speech in apraxia of speech and hypokinetic dysarthria

ABSTRACT Speakers with motor speech disorders (MSD) present challenges in speech production, one of them being the difficulty to adapt their speech to different modes. However, it is unclear whether different types of MSD are similarly affected when it comes to adapting their speech to various communication contexts. This study investigates the encoding of speech modes in individuals with AoS following focal brain damage and in individuals with hypokinetic dysarthria (HD) secondary to Parkinson’s disease. Participants with mild-to-moderate MSD and their age-matched controls performed a delayed production task of pseudo-words in two speech modes: normal and whispered speech. While overall accuracy did not differ significantly across speech modes, participants with AoS exhibited longer response latencies for whispered speech, reflecting difficulties in the initiation of utterances requiring an unvoiced production. In contrast, participants with HD showed faster response latencies for whispered speech, indicating that this speech mode is easier to encode/control for this population. Acoustic durations followed these same trends, with participants with AoS showing greater lengthening for whispered speech as compared to controls and to participants with HD, while participants with HD exhibited milder lengthening. Contrary to the predictions of speech production models, suggesting that speech mode changes might be particularly difficult in dysarthria, the present results suggest that speech mode adaptation rather seems particularly costly for participants with AoS.

Differential spectral characteristics of the Spanish fricative /s/ in the articulation of individuals with dysarthria and apraxia of speech

PurposeThis study examines whether there are differences in the speech of speakers with dysarthria, speakers with apraxia and healthy speakers in spectral acoustic measures during production of the central-peninsular Spanish alveolar sibilant fricative /s/. MethodTo this end, production of the sibilant was analyzed in 20 subjects with dysarthria, 8 with apraxia of speech and 28 healthy speakers. Participants produced 12 sV(C) words. The variables compared across groups were the fricative's spectral amplitude difference (AmpD) and spectral moments in the temporal midpoint of fricative execution. ResultsThe results indicate that individuals with dysarthria can be distinguished from healthy speakers in terms of the spectral characteristics AmpD, standard deviation (SD), center of gravity (CoG) and skewness, the last two in context with unrounded vowel, while no differences in kurtosis were detected. Participants with AoS group differ significantly from healthy speaker group in AmpD, SD and CoG and Kurtosis, the first one followed unrounded vowel and the latter two followed by rounded vowels. In addition, speakers with apraxia of speech group returned significant differences with respect to speakers with dysarthria group in AmpD, CoG and skewness. ConclusionsThe differences found between the groups in the measures studied as a function of the type of vowel context could provide insights into the distinctive manifestations of motor speech disorders, contributing to the differential diagnosis between apraxia and dysarthria in motor control processes.