Acoustic characteristics of vowels produced by Greek intelligible speakers with profound hearing impairment II: The influence of stress and context

Purpose: The present paper examines the influence of stress and context on selected acoustic characteristics of vowels produced by six adult Greek intelligible speakers with profound hearing impairment and six speakers with normal hearing (three males and three females in each group).

Method: F1, F2 and F3 formant frequencies and the duration of vowels are measured in words of the form /^′pVCV/ with V = /i, ?, ?, ?, u/ and C = /p, t, k, s/. Variation in these parameters due to context and stress is reported for the two genders. A co-articulatory measure and three measures that examine the area of the vowel space and differences along the F1 and F2 axes are calculated.

Result: The results show a reduction of the vowel space in the unstressed condition for both groups, while vowel duration was found to be significantly longer in this condition for the speakers with hearing impairment. In addition, smaller C-to-V carryover co-articulatory effects were found for the speakers with hearing impairment.

Conclusion: Findings are discussed within the framework of perceptual and production constraints in hearing impairment and with reference to current models of co-articulation.     

Acoustic characteristics of vowels produced by Greek intelligible speakers with profound hearing impairment I: Examination of vowel space

Purpose: The study examines F1, F2 and F3 formant frequencies of vowels produced by six Greek intelligible speakers with profound hearing impairment and six speakers with normal hearing (three male and three female in each group).

Method: The formant frequencies are measured in words of the form /?pVCV/ where V?=?/i, ?, ?, ?, u/ and C?=?/p, t, k, s/. The study examines differences in formant frequencies between the two groups and as a function of gender. Three measures are calculated to examine the area of the vowel space and differences along the F1 and F2 axes between the groups and genders.

Result: The results show that the vowel space produced by the speakers with hearing impairment is considerably reduced. Greater reduction was evident for F2 compared to F1. Restricted formant frequency ranges and relatively large variation along F1 and/or F2 for selected vowels resulted in overlap among vowel categories. F3 frequencies were systematically lower and showed greater variation for the speakers with hearing impairment.

Conclusion: The paper discusses findings with reference to perceptual and production constraints affecting the speech of individuals with hearing impairment.     

The cognitive competence of speakers with acquired dysarthria: Judgements by doctors and speech and language therapists

Background.?Studies have shown that listeners make negative attributions towards people with communication impairments. This appears to be the case for healthcare professionals as well as non-professional listeners.

Aims.?This study extends this line of research to speakers with acquired dysarthria. These clients often complain that listeners treat them differently after the onset of their speech impairment. The study examines judgements of the cognitive status of speakers with acquired dysarthria made by health care professionals.

Methods and procedures.?Doctors, speech and language therapists and speech and language therapy students viewed videos of speakers with acquired dysarthria and of controls matched for age and gender who had acquired neurological deficits that did not affect their speech. Listeners judged whether speakers could carry out a number of everyday tasks. All the tasks were known to be within the speakers' competence.

Outcomes and results.?Doctors were significantly less confident of the competence of speakers with dysarthria than of the controls. No difference was found for speech and language therapists or speech and language therapy students.

Conclusions Although caution is required in generalizing these results to other speakers, the results lend some support to the complaints of clients with acquired dysarthria that their speech leads others, in this case doctors, to misjudge their cognitive competence.     

Production of word-initial fricatives of Mandarin Chinese in prelingually deafened children with cochlear implants

Purpose: This study examined the production of fricatives by prelingually deafened Mandarin-speaking children with cochlear implants (CIs).

Method: Fourteen cochlear implant (CI) children (2.9–8.3 years old) and 60 age-matched normal-hearing (NH) children were recorded producing a list of 13 Mandarin words with four fricatives, /f, s, ?, ?/, occurring at the syllable-initial position evoked with a picture-naming task. Two phonetically-trained native Mandarin speakers transcribed the fricative productions. Acoustic analysis was conducted to examine acoustic measures including duration, normalised amplitude, spectral peak location and four spectral moments.

Result: The CI children showed much lower accuracy rates and more diverse error patterns on all four fricatives than their NH peers. Among these four fricatives, both CI and NH children showed the highest rate of mispronunciation of /s/. The acoustic results showed that the speech of the CI children differed from the NH children in spectral peak location, normalised amplitude, spectral mean and spectral skewness. In addition, the fricatives produced by the CI children showed less distinctive patterns of acoustic measures relative to the NH children.

Conclusion: In general, these results indicate that the CI children have not established distinct categories for the Mandarin fricatives in terms of the place of articulation.     

Sentence stress in children with dysarthria and cerebral palsy

Abstract

Purpose: This study aimed to advance our understanding of how children with dysarthria and cerebral palsy (CP) realise sentence stress acoustically, and how well listeners could identify the position of the stressed word within these utterances.

Method: Seven children with CP and eight typically developing children participated in the experiment. Stress on target words in two sentence positions was elicited through a picture-based question–answer paradigm. Acoustic parameters of stress [duration, intensity and fundamental frequency (F0)] were measured and compared between stressed and unstressed target words. For the perception experiment, ten listeners were asked to determine the position of the stressed word in the children’s productions.

Result: Acoustic measures showed that at group level the typically developing children used all three acoustic parameters to mark sentence stress, whereas the children with CP showed changes in duration only. Individual performance variations were evident in both groups. Perceptually, listeners were significantly better at identifying the stressed words in the utterances produced by the typically developing children than those of the children with CP.

Conclusion: The results suggest that children with CP can manipulate temporal speech properties to mark stress. This ability to modulate acoustic–prosodic features could be harnessed in intervention to enhance children’s functional communication.     

Lexical stress in childhood apraxia of speech: acoustic and kinematic findings

Abstract

Purpose: This study investigated the acoustic and articulatory movement parameters underlying lexical stress production in children with apraxia of speech (CAS), children with articulation/phonological delay (i.e. speech delay, SD), and children with typical speech-language development (TD). We examined whether there were group differences in these instrumental measures of stress production.

Method: Participants were 24 children (seven CAS, eight SD, nine TD) between three and seven years of age. Acoustic and kinematic measures, including acoustic duration, peak and average fundamental frequency, and jaw movement duration and displacement, were taken from perceptually accurate productions of a strong-weak form. Relative stress analyses were conducted using the Pairwise Variability Index (PVI).

Result: There was a significant difference between the CAS and TD groups in the PVI for movement duration, with the CAS group showing a smaller movement duration contrast between stressed and unstressed syllables. There were no significant group differences for displacement or any of the acoustic variables.

Conclusion: The kinematic findings suggest reduced temporal control for lexical stress production in children with CAS. This finding surfaced during analyses of perceptually accurate productions but suggests a possible basis for lexical stress errors in CAS that could be explored in future studies.     

Tongue-palate contact patterns for Japanese speakers with and without cleft lip and palate

Abstract

Purpose: Visual feedback therapy, using electropalatography (EPG), has been used to remedy residual articulation errors associated with cleft palate. The tongue-palate contact patterns of typical speakers without cleft palate are usually used as a model. However, it is questionable whether these model patterns are adequate for clients with repaired cleft palate, as their dento-palatal morphology is different from non-cleft speakers. The objective of this study was to investigate the differences in tongue-palate contact patterns between typical speakers with and without cleft palate.

Method: EPG data were recorded for alveolar consonants in 15 participants with repaired unilateral cleft lip and palate (UCLP) whose speech was perceptually assessed as typical Japanese. The cumulative templates for each consonant were generated from the maximum contact frame; quantitative analyses (centre of gravity [CoG], variability index) were performed. Fifteen typical Japanese speakers without cleft served as a control group.

Result: EPG patterns for each consonant were generally similar between groups. The CoG value of the UCLP group was significantly lower only for /s/. The average variability index was higher for every consonant but the comparisons did not reach significance.

Conclusion: The typical tongue-palate contact patterns can be used as a model of visual feedback therapy.     

Changes to articulation following LSVT® and traditional dysarthria therapy in non-progressive dysarthria

The present study aimed to evaluate the effects of the Lee Silverman Voice Treatment (LSVT®) on acoustic and perceptual measures of articulation in non-progressive dysarthria in comparison to traditional dysarthria therapy. The study involved 26 individuals with non-progressive dysarthria who were randomly allocated to receive either LSVT® or traditional dysarthria therapy (TRAD), both of which were administered for 16 hourly sessions over 4 weeks. Participants' speech samples were collected over a total of six testing sessions during three assessment phases: (1) prior to treatment, (2) immediately post-treatment, and (3) 6 months post-treatment (FU). Speech samples were analysed perceptually to determine articulatory precision and intelligibility as well as acoustically using vowel space (and vowel formant measures) and first moment differences. Results revealed short and long-term significant increases in vowel space area following LSVT®. Significantly increased intelligibility was also found at FU in the LSVT® group. No significant differences between groups for any variables were found. The study reveals that LSVT® may be a suitable treatment option for improving vowel articulation and subsequent intelligibility in some individuals with non-progressive dysarthria.     

Therapeutic effects of intensive voice treatment (LSVT LOUD®) for children with spastic cerebral palsy and dysarthria: A phase I treatment validation study

Purpose: The aim of the present study was to validate and extend the evaluation of treatment outcomes following LSVT LOUD® in children with dysarthria secondary to cerebral palsy (CP).

Method: Seven children (5 females, 6–10 years) with spastic quadriplegia and dysarthria received LSVT LOUD. Outcomes included: (a) quantitative and qualitative indices of communication and social functioning representing therapeutic effects and (b) features of the acoustic signal representing physiological effects on the speech mechanism. A matched group of typically developing children served as controls. Testing occurred just prior to (PRE), immediately following (POST), and at 12 weeks post-treatment (FUP).

Result: Expert listeners preferred voice quality and articulatory precision of children with CP at FUP as compared to PRE. Acoustic data indicated improvements on select measures of vocal functioning at POST with some maintenance at FUP. Single word intelligibility improved immediately POST, but was not maintained at FUP. Parents rated positive changes in characteristics of voice and speech and qualitative changes in communication at both POST and FUP.

Conclusion: The present study validated some of the previous LSVT LOUD outcomes in children with dysarthria and CP and extended our understanding of therapeutic effects through qualitative data obtained from extensive parent interviews.     

Intra-participant variability in Parkinson's disease: An electropalatographic examination of articulation

The articulation of individuals with dysarthria has traditionally been described as consistent. However, conflicting findings have resulted from research examining intra-participant variation in the articulation of individuals with Parkinson's disease (PD) and hypokinetic dysarthria. The current study used electropalatography (EPG) to examine the degree of intra-participant variation in both tongue-palate contact patterns and duration of contact in a group of speakers with PD and hypokinetic dysarthria including consonant imprecision (n = 8). The study also aimed to determine if ageing contributed to any articulatory instability observed. Therefore, two control groups were employed consisting of aged adult (n = 7) and young adult (n = 8) speakers respectively. Participants were asked to read aloud the phrase “I saw a CVC today” were C = /t/, /s/, and /l/ and V = /a/. Intra-participant variation in tongue-palate contact was measured using the absolute and relative variability indexes. Coefficients of variation of duration of tongue contact were employed to examine intra-participant variation in consonant duration. In contrast to the study hypotheses, similar levels of intra-participant variation were observed across the three groups. However, a trend towards increased intra-participant variation in consonant duration was noted in the group with PD. The results of the study suggest that, at least spatially, the articulatory errors of individuals with PD are consistent across repetitions. Research including increased participant numbers and individuals exhibiting greater severity of dysarthria is required to provide further understanding of intra-participant variation in consonant duration in PD.     

脑卒中构音障碍患者元音产出特征与言语清晰度的相关性

目的 探讨脑卒中后构音障碍患者的元音产出特征改变及其与言语清晰度之间的关系.方法 2019年10月至2020年1月,选择脑卒中后构音障碍患者19例(脑卒中组)和健康成人18例(对照组),朗读一段语音均衡材料,分析元音产出声学特征,包括下颌距、舌距、F2i/F2u、元音空间面积(VSA)、元音清晰度指数(VAI)、F1变...     

Dysarthria and dysphagia are highly prevalent among various types of neuromuscular diseases

Abstract

Purpose: Patients with a neuromuscular disease (NMD) can present with dysarthria and/or dysphagia. Literature regarding prevalence rates of dysarthria and dysphagia is scarce. The purpose of this study was to determine prevalence rates, severity and co-presence of dysarthria and dysphagia in adult patients with NMD. Method: Two groups of adult patients with NMD were included: 102 consecutive outpatients (the “unselected cohort”) and 118 consecutive patients who were referred for multidisciplinary assessment (the “selected cohort”). An experienced speech-language pathologist examined each patient in detail. Results: The pooled prevalence of dysarthria was 46% (95% CI: 36.5–55.9) and 62% (95% CI: 53.3–70.8) in the unselected and selected cohorts, respectively. The pooled prevalence of dysphagia was 36% (95% CI: 27.1–45.7) and 58% (95% CI: 49.4–67.2) in the unselected and selected cohorts, respectively. There was a modest but significant association between the presence of dysarthria and dysphagia (r_s?=?0.40; p?<?0.01). Although the dysphagia was generally mild, dysarthria was moderate to severe in 15% of the dysarthric patients. Conclusion: The prevalence rates of dysarthria and dysphagia among patients with various types of NMD are high. Physicians should therefore be aware of this prevalence and consider referring NMD patients to a speech-language pathologist.

• Implicatons of Rehabilitation

• Both dysarthria and dysphagia are highly prevalent among patients with neuromuscular diseases; moreover, although often mild, these disorders can occur relatively early in the course of the disease.

• Clinicians should routinely check for signs and symptoms related to dysarthria and/or dysphagia in patients who present with a neuromuscular disease, preferably using standardised instruments.

     

Criterion-related validity of the Test of Children's Speech sentence intelligibility measure for children with cerebral palsy and dysarthria

Abstract

Purpose: To evaluate the criterion-related validity of the TOCS+ sentence measure (TOCS+, ) for children with dysarthria and CP by comparing intelligibility and rate scores obtained concurrently from the TOCS+ and from a conversational sample.

Method: Twenty children (3 to 10 years old) diagnosed with spastic cerebral palsy (CP) participated. Nineteen children also had a confirmed diagnosis of dysarthria. Children's intelligibility and speaking rate scores obtained from the TOCS+, which uses imitation of sets of randomly selected items ranging from 2–7 words (80 words in total) and from a contiguous 100-word conversational speech were compared.

Results: Mean intelligibility scores were 46.5% (SD = 26.4%) and 50.9% (SD = 19.1%) and mean rates in words per minute (WPM) were 90.2 (SD = 22.3) and 94.1 (SD = 25.6), respectively, for the TOCS+ and conversational samples. No significant differences were found between the two conditions for intelligibility or rate scores. Strong correlations were found between the TOCS+ and conversational samples for intelligibility (r = 0.86; p < 0.001) and WPM (r = 0.77; p < 0.001), supporting the criterion validity of the TOCS+ sentence task as a time efficient procedure for measuring intelligibility and rate in children with CP, with and without confirmed dysarthria.

Conclusion: The results support the criterion validity of the TOCS+ sentence task as a time efficient procedure for measuring intelligibility and rate in children with CP, with and without confirmed dysarthria. Children varied in their relative performance on the two speaking tasks, reflecting the complexity of factors that influence intelligibility and rate scores.     

Progressive speech deterioration and dysphagia in amyotrophic lateral sclerosis: case report.

Amyotrophic lateral sclerosis (ALS) is a degenerative neurologic disease having both upper and lower motor neuron signs and symptoms. When the speech musculature is involved, a mixed dysarthria and dysphagia usually result. In a 49-year-old man with ALS, dysarthria and dysphagia progressed from mild to severe forms over 17 months. Eleven months after the patient first experienced symptoms, neurologic examination showed fasciculations of the extremities and tongue, limb weakness, and hyperreflexia of the limbs and velopharyngeal mechanism. Tongue strength was one-fourth that of normal. Lingual alternate motions rates for consonant-vowel syllables were also reduced. To enhance lingual strength and swallowing, a tongue-strengthening program was developed for use with articulation training; to augment velopharyngeal function, a palatal lift was fitted; and to increase extremity strength, physical therapy was initiated. Six months after the initial neurologic examination, medical and speech reevaluation showed progressive weakness of the body parts affected initially; continued decline in tongue strength and lingual alternate motion rate; hypoactive reflex activity, indicative of progressive involvement of the lower motor neuron system; and continued deterioration of articulation and phonation owing to the progressive nature of the disease.     

Intonation patterns in older children with cerebral palsy before and after speech intervention

Purpose: This paper examined the production of intonation patterns in children with developmental dysarthria associated with cerebral palsy (CP) prior to and after speech intervention focussing on respiration and phonation. The study further sought to establish whether intonation performance might be related to changes in speech intelligibility.

Method: Intonation patterns were examined using connected speech samples of 15 older children with moderate to severe developmental dysarthria due to CP (9 females; age range: 11–18). Recordings were made prior to and after speech intervention based on a systems approach. Analyses are focussed on the use of intonation patterns, pitch accentuation and phrasing.

Result: Group analyses showed a significant increase in the use of rising intonation patterns after intervention. There were also some indications that this increase might have been related to gains in speech intelligibility for some of the children. No changes were observed regarding pitch accentuation and phrasing following intervention.

Conclusion: The findings highlight that changes can occur in the use of intonation patterns in children with dysarthria and CP following speech systems intervention. It is hypothesised that the emergence of the rising pattern in some of the children’s intonational inventories possibly reflected improved breath support and control of laryngeal muscles.     

Effects of transcranial direct current stimulation over the Broca’s area on tongue twister production

Purpose: The present study aimed to explore the short-term effect of anodal transcranial direct current stimulation (tDCS) on tongue twister production.

Method: Thirty healthy native Cantonese adult speakers were randomly assigned to the anodal tDCS group or the sham tDCS group. Anodal tDCS of 2?mA was applied over the Broca’s area of the brain. The stimulation lasted for 20?min for the anodal tDCS group and 30?s for the sham tDCS group. The participants were instructed to produce a list of tongue twisters before, immediately after and 4?h after tDCS.

Result: Speech rate and response accuracy measured immediately after stimulation were significantly faster and higher, respectively, than before stimulation. Although there was no change in speech rate measured at 4?h after stimulation, response accuracy at that time point was significantly lower than that measured immediately after stimulation. However, there were no significant differences between the anodal tDCS and sham tDCS groups in either speech rate or response accuracy.

Conclusion: The findings revealed that a single session of anodal tDCS over the Broca’s area did not significantly improve speech production during tongue twister production.     

Living with acquired dysarthria: the speaker's perspective

Purpose.?To explore the speaker's experience of living with acquired chronic dysarthria.

Method.?Ten people with dysarthria and progressive neurological illness and one person with dysarthria following stroke were interviewed in depth about their experience of living with dysarthria. They covered a range of ages, time post-onset and dysarthria severity levels. Interviews were transcribed and analysed using Framework Method of Analysis.

Results.?Acquired dysarthria can negatively impact on speakers' lives. Findings here suggest that the experience of living with dysarthria is highly individual. There were some common perspectives. Six key themes emerged from interviews: ‘dysarthria as only part of the picture’, ‘communication has changed’, ‘people treat me differently’, ‘dysarthria resulting in negative emotions’, ‘barriers to communication’ and ‘life is different now. The impact of co-existing physical disability and the need to consider dysarthria in context was emphasised by all participants.

Conclusion.?Findings re-emphasise the need to consider the individual experience in clinical practice. The findings provide direction for assessment and intervention in the area.     

Understanding and measuring powered wheelchair mobility and manoeuvrability. Part I. Reach in confined spaces

Purpose.?To determine: (1) what wheelchair manoeuvrability factors are important and (2) the effects of powered wheelchair design on the ability to reach in a confined space.

Method.?The relative importance of five aspects of wheelchair manoeuvrability was determined through a survey of users of wheelchairs (N?=?52) and health care professionals and others (N?=?89). A single young, non-disabled subject undertook repeated trials of reach distance on to a counter at the end of a corridor whose width could be adjusted by moving Styrofoam walls.

Results.?Reaching, moving in confined spaces and avoiding collisions were more important than speed and avoiding the need to drive backwards. The rear wheel drive powered wheelchair was found to allow the greatest reach when driving backwards into the space and the wheelchair which moved in a sideways direction allowed greatest reach in the narrowest corridor.

Conclusions.?The survey concluded that manoeuvring in small spaces and reaching without collisions were important. The powered wheelchair with sideways capability afforded the greatest reach in confined spaces except when the rear wheel drive chair was driven in backwards. The survey respondents did not place a high priority on avoiding backwards driving but some people find this difficult to do safely.     

鼻咽癌放疗后构音障碍患者舌尖音的舌尖上抬幅度和速度研究

目的:分析鼻咽癌放疗后构音障碍患者舌尖音的舌尖上抬幅度和速度,探讨肌肉纤维化影响舌构音运动的机制。方法:鼻咽癌放疗后构音障碍患者和正常对照受试者读出汉语构音障碍评估的单词检查表,利用麦克风和电磁发音仪(EMA)同步记录受试者的语音信号和舌尖运动数据。根据检查表中四个包含舌尖辅音词语的音频信号,截取发音前舌尖上抬的动作数据,计算得到舌尖运动的幅度和平均速度,采用重复性方差分析比较两组受试者间,以及不同辅音—元音组合间的舌运动特征。结果:构音障碍患者组和对照组舌尖音的舌尖上抬幅度没有显著性差异;不送气舌尖音/d/后接舌位较高的复元音/ian/时,舌尖上抬的幅度大于舌位较低的复元音/ai/。患者组舌尖上抬的平均速度明显小于对照组;送气舌尖音/t/舌尖上抬的平均速度显著高于不送气音/d/;后续元音为/ian/时平均速度大于元音为/ai/时。结论:鼻咽癌放疗后构音障碍患者舌的运动速度先于运动幅度受到肌肉纤维化的影响,送气与不送气舌尖音后续不同舌位元音时具有特异性的发音机制。