The Effects of Intensive Speech Treatment on Intelligibility in Spanish Speakers with Parkinson's Disease

The motivation of this study was to examine the effects of intensive speech treatment on the conversational intelligibility of Spanish speakers with Parkinson’s Disease (PD). It also aimed at investigating several acoustic variables in the speech of this population. Sixteen speakers with a medical diagnosis of PD participated in this study and their voice recordings were analyzed pre- and post-treatment. The intelligibility measures of transcription accuracy and median ease-of-understanding ratings increased significantly immediately post-treatment and gains were maintained at the one-month follow-up. The acoustic variables of vowel space and voice onset time did not change significantly pre-to-post treatment, whilst the prosodic targets of intensity and mean fundamental frequency increased significantly as a result of treatment. These findings support the implementation of intensive voice intervention to improve intelligibility in Spanish dysarthria. Clinical and theoretical considerations are discussed

The effects of intensive speech treatment on conversational intelligibility in Spanish speakers with Parkinson’s disease

Purpose: To examine the effects of intensive speech treatment on the conversational intelligibility of Castilian Spanish speakers with Parkinson’s disease (PD), as well as on the speakers’ self-perceptions of disability. Method: Fifteen speakers with a medical diagnosis of PD participated in this study. Speech recordings were completed twice before treatment, immediately post-treatment and at a one-month follow-up session. Conversational intelligibility was assessed in two ways—transcription accuracy scores and intelligibility ratings on a 9-point Likert scale. The Voice Handicap Index (VHI) was administered as a measure of self-perceived disability. Results: Group data revealed that transcription accuracy and median ease-of-understanding ratings increased significantly immediately post-treatment, with gains maintained at the one-month follow-up. The functional subscale of the VHI decreased significantly post-treatment, suggesting a decrease in perceived communication disability after speech treatment. Conclusion: These findings support the implementation of intensive voice treatment to improve conversational intelligibility in Spanish speakers with PD with dysarthria as well as to improve the speakers' perception of their daily communicative capabilities. Clinical and theoretical considerations are discussed

Vowel Intelligibility in Children With and Without Dysarthria: An Exploratory Study

Children with dysarthria due to cerebral palsy (CP) present with decreased vowel space area and reduced word intelligibility. Although a robust relationship exists between vowel space and word intelligibility, little is known about the intelligibility of vowels in this population. This exploratory study investigated the intelligibility of American-English vowels produced by children with dysarthria and typically-developing children (TD). Three CP and five TD repeated words with contrastive vowels /i-ɪ/,/æ-ɛ/,/ɑ-ʌ/,/o-u/ produced by a native American-English adult. Adult listeners transcribed the utterances orthographically and rated their ease of understanding. Overall, CP presented with less-intelligible vowels than TD. For CP, a trend was found with the lowest intelligibility for /ɑ/ (CP=7%,TD=66%), /ɪ/ (CP=30%,TD=82%), and /ʌ/ (CP=38%,TD=99%), and more heterogeneous vowel confusions; however, intelligibility differences between vowels did not reach statistical significance. Clinical implications include that, unless further studies show vowel-specific effects, treatment targeting the entire vowel system may be warranted for increasing intelligibility

Accent modification as a raciolinguistic ideology: a commentary in response to Burda et al. (2022)

In this commentary, we collectively examine a recent article titled “Effectiveness of Intense Accent Modification Training with Refugees from Burma” by Burda et al. (2022). Whilst our response is aimed at revealing the theoretical and methodological shortcomings of Burda et al., it will also expose the raciolinguistic ideologies in accent modification and highlight the need for careful ethical considerations on vulnerable populations, such as refugees and asylum seekers

Automatic Assessment of Intelligibility in Noise in Parkinson Disease: Validation Study

BackgroundMost individuals with Parkinson disease (PD) experience a degradation in their speech intelligibility. Research on the use of automatic speech recognition (ASR) to assess intelligibility is still sparse, especially when trying to replicate communication challenges in real-life conditions (ie, noisy backgrounds). Developing technologies to automatically measure intelligibility in noise can ultimately assist patients in self-managing their voice changes due to the disease. ObjectiveThe goal of this study was to pilot-test and validate the use of a customized web-based app to assess speech intelligibility in noise in individuals with dysarthria associated with PD. MethodsIn total, 20 individuals with dysarthria associated with PD and 20 healthy controls (HCs) recorded a set of sentences using their phones. The Google Cloud ASR API was used to automatically transcribe the speakers’ sentences. An algorithm was created to embed speakers’ sentences in +6-dB signal-to-noise multitalker babble. Results from ASR performance were compared to those from 30 listeners who orthographically transcribed the same set of sentences. Data were reduced into a single event, defined as a success if the artificial intelligence (AI) system transcribed a random speaker or sentence as well or better than the average of 3 randomly chosen human listeners. These data were further analyzed by logistic regression to assess whether AI success differed by speaker group (HCs or speakers with dysarthria) or was affected by sentence length. A discriminant analysis was conducted on the human listener data and AI transcriber data independently to compare the ability of each data set to discriminate between HCs and speakers with dysarthria. ResultsThe data analysis indicated a 0.8 probability (95% CI 0.65-0.91) that AI performance would be as good or better than the average human listener. AI transcriber success probability was not found to be dependent on speaker group. AI transcriber success was found to decrease with sentence length, losing an estimated 0.03 probability of transcribing as well as the average human listener for each word increase in sentence length. The AI transcriber data were found to offer the same discrimination of speakers into categories (HCs and speakers with dysarthria) as the human listener data. ConclusionsASR has the potential to assess intelligibility in noise in speakers with dysarthria associated with PD. Our results hold promise for the use of AI with this clinical population, although a full range of speech severity needs to be evaluated in future work, as well as the effect of different speaking tasks on ASR

The effects of intensive speech treatment on intelligibility in Parkinson’s disease: a randomised controlled trial

Background: More than 6,000,000 individuals worldwide are diagnosed with Parkinson’s disease (PD). Nearly 90% develop speech signs that may substantially impair their speech intelligibility, resulting in losses in their communication and quality of life. Benefits of intensive speech treatment have been documented for a range of speech signs. However, the critical question of whether speech is more intelligible after treatment has not been investigated in a randomised controlled trial (RCT). We hypothesised that intensive speech treatment would improve speech intelligibility in PD. Method: Sixty-four patients with hypokinetic dysarthria secondary to PD participated in this single-centre, parallel arm, statistically-powered RCT. Reporting follows CONSORT guidelines for non-pharmacological treatment. Patients were recruited from US clinics and randomised using a statistician-derived minimisation algorithm, to intensive speech treatment (16 1-hour sessions/1 month) targeting voice (voice group) or targeting articulation (articulation group) or to an untreated group (no treatment group). Speech treatments were delivered by speech clinicians who specialised in treating patients with PD. Trial design minimised bias and supported equipoise. For intelligibility assessment, blinded listeners (n=117) orthographically transcribed 57 patients’ recorded, self-generated narrative speech samples, randomly presented. Listeners were American-English speakers, ages 18-35 years, with normal hearing. The primary outcome was baseline (pre-treatment) to post-treatment change in transcription accuracy (TA), recognised as the most objective measure of intelligibility. TA was defined as the percentage of words transcribed correctly. Listeners, data collectors, and data managers were blinded to treatment conditions and groups. Reliability was evaluated using intraclass correlation coefficients and differences among groups were evaluated by mixed-effects models, in accordance with the intention-to-treat approach. This trial was registered with ClinicalTrials.gov Identifier: NCT00123084. Findings: Between June 23, 2016 and August 14, 2017, blinded listeners transcribed baseline and post-treatment speech samples for intelligibility assessment of 57 patients in the voice (n=19), articulation (n=19) and no treatment (n=19) groups. Between-group differences (d) in changes from baseline to post-treatment in TA indicated significantly greater increases following treatment targeting voice than treatment targeting articulation (d=26·2%, 95% CI 1·5−51·0; p=0·04; ES=1·0). Differences between TA changes in the treatment targeting voice and in the no treatment group were significant (d=42·8%, 95% CI 22·4−63·2; p=0·0002; ES=1·8). Differences between TA changes in the treatment targeting articulation and in the no treatment group were not significant (d=16·5%, 95% CI -6·1−39·2; p=0·147; ES=0·9). Interpretation: These findings provide the first RCT evidence that intensive speech treatment targeting voice improves speech intelligibility in PD. Thus, this evidence-based treatment may positively impact health-related quality of life for patients with PD globally when it is included in patient management