Analysis of Voice in Parkinson's Disease Utilizing the Acoustic Voice Quality Index.

OBJECTIVES: The purpose of this study was to analyze the acoustic voice quality index (AVQI) in relation to perceptual analysis and disease stage in speakers with Parkinson's disease (PD). STUDY DESIGN: Cross-sectional study. METHODS: The following data were gathered from the Parkinson's Disease Speech corpus of Tampere University (PDSTU): prolonged vowels and reading samples from native Finnish speakers with PD (n = 34), speaker demographic information, and Hoehn and Yahr scale scores. AVQIv03.01 analysis was completed with Praat. Expert raters utilized the GRBASI scale (GRBASI: grade, roughness, breathiness, asthenia, strain, instability) to assess voice quality. AVQI scores were analyzed in relation to GRBASI ratings and disease stage, as measured by the Hoehn and Yahr scale, utilizing correlation analysis. RESULTS: AVQI scores ranged from -0.11 to 4.46 (mean = 1.64, SD = 1.39), GRBASI average total scores ranged from 0-1.83 (mean = 0.66, SD = 0.50), and Hoehn and Yahr scale scores ranged from 1- 4. A statistically significant correlation between AVQI scores and GRBASI ratings was found (rs = 0.508, P = 0.01). Several significant correlations were also found between the parameters of AVQI and scores for G, R, B and A from GRBASI. Hoehn and Yahr scores correlated significantly with GRBASI total score (rs =0.437, P = 0.01) but not with AVQI. CONCLUSION: A significant correlation was found between GRBASI ratings and Hoehn and Yahr scores, but not between AVQI and Hoehn and Yahr scores. DATA AVAILABILITY: Due to the nature of this research, participants of this study did not agree for their data to be shared publicly. Data may be made available on a case-by-case basis. Data will be available after the active phase of the study in 2028.

Functional data analysis of prosodic prominence in Parkinson's disease: a pilot study.

This study aims to reveal dynamic changes in prosodic prominence patterns associated with Parkinson's disease (PD). To fulfill this purpose, the study proposes an exploratory methodology involving measuring a novel syllable-based prosody index (SPI) and performing functional principal component analyses (fPCAs) in a semi-automatic manner. First, SPI trajectories were collected from 31 speakers with PD before and after speech therapy and from 36 healthy controls. Then, the SPI trajectories were converted to continuous functions using B-splines. Finally, the functional SPIs were examined using fPCAs. The results showed that PD was associated with an increase of overall prominence for male speakers. The findings regarding higher prominence patterns in PD were supported by traditional phonetic measurements. For female speakers, however, there were no significant differences in prosodic prominence between speakers with PD and healthy controls. The results encourage to explore the proposed methodology also in analyses of other forms of atypical speech.

A comparative study of automatic vowel articulation index and auditory-perceptual assessments of speech intelligibility in Parkinson's disease.

PURPOSE: The purpose of this study was to analyse the relationship between automatic vowel articulation index (aVAI) and direct magnitude estimation (DME) among speakers with Parkinson's disease (PD) and healthy controls. We further analysed the potential of aVAI to serve as an objective measure of speech impairment in the clinical setting. METHOD: Speech samples from native Finnish speakers were utilised. Expert raters utilised DME to scale the intelligibility of speech samples. aVAI scores for PD speakers and healthy control speakers were analysed in relationship to DME speech intelligibility ratings and, among PD speakers, disease stage utilising nonparametric statistical analysis. RESULT: Mean DME intelligibility ratings were lower among PD speakers compared to healthy controls. Mean aVAI scores were nearly the same between speaker groups. DME intelligibility ratings and aVAI were strongly correlated within the PD speaker group. aVAI and DME intelligibility ratings were moderately correlated with disease stage as measured by the Hoehn and Yahr scale. CONCLUSION: aVAI was observed to be a promising tool for analysing vowel articulation in PD speakers. Further research is warranted on the application of aVAI as an objective measure of severity of speech impairment in the clinical setting, with varying patient populations and speech samples.

Prosodic features in Finnish-speaking adults with Parkinson´s disease.

The aim of this study was to assess prosodic features in Finnish speakers with (n = 16) and without (n = 20) Parkinson's disease (PD), as there are no published studies to date of prosodic features in Finnish speakers with PD. Chosen metrics were articulation rate (syllables/second), pitch (mean F0) and pitch variability (standard deviation F0), energy proportion below 1 kHz (epb1kHz), normalised pairwise variability index (nPVI), and a novel syllabic prosody index (SPI). Four statistically significant results were found: (1) energy was distributed more to lower frequencies in speakers with PD compared to control speakers, (2) male PD speakers had higher pitch and (3) higher syllabic prosody index compared to control males, and (4) female PD speakers had narrower pitch variability than controls. In this study, PD was manifested as less emphatic and breathier voice. Interestingly, male PD speakers' dysprosody was manifested as an effortful speaking style, whereas female PD speakers exhibited dysprosody with a monotonous speaking style. A novel syllable-based prosody index could be a potentially useful tool in analysing prosody in disordered speech.

Disfluency clusters in typical and atypical finnish adult speech. A pilot study.

This study first aimed to investigate disfluency clusters in typical and atypical Finnish adult speakers. Secondly, it aimed to observe possible fluency strategies in speakers representing different fluency levels. In addition to individual disfluency types, we examined different characteristics of disfluency clusters produced by 23 speakers in a fluency continuum. Three adult speaker groups participated in this study: typical speakers with high disfluency frequencies (GA), typical and atypical speakers with very high disfluency frequencies (GB) and atypical speakers with the highest disfluency frequencies (GC). Data were based on a narrative speech task, and disfluency clusters were analysed with both traditional methods and alternative methods. Two statistically significant differences between the speaker groups were found: 1) the length of the clusters was highest in GC compared to other groups, and 2) speakers in GC formulated their utterances more than other groups. Other results, although nonsignificant, were that 3) speakers in GA revised utterances more often than interrupted them compared to GB and GC speakers, and 4) clusters using repetitive words and phrases to maintain fluency were found in GA and GB only. In this study, different fluency levels revealed different strategies in both the production of single disfluencies and in disfluency clusters. It seems that more fluent speakers formulate their messages differently than less fluent speakers, and repetitions can be used to maintain fluency and possibly prevent difficult clusters, as noted with more fluent speakers.

Disfluency clusters in speakers with and without neurogenic stuttering following traumatic brain injury.

PURPOSE: Analyze the characteristics and rate of disfluency clusters in adults with and without neurogenic stuttering after traumatic brain injury (TBI). METHOD: Twenty adults with TBI participated in this study, including 10 with neurogenic stuttering (Group B) and 10 without -stuttering (Group A). Disfluency clusters in speech samples were classified into three types: Stuttering-like (SLD), other (OD), and mixed (MIX). RESULTS: Speakers with and without neurogenic stuttering produced the same mean number of disfluency clusters. In addition, the mean length of clusters did not differ between these speaker groups although the longest clusters did. The most frequently occurring cluster type for people with neurogenic stuttering was MIX and OD for people without stuttering. Although the speakers in Group A produced stuttering-like disfluencies, these never occurred together to form a SLD type cluster. For Group B, the starter units of the clusters were usually stuttering-like disfluencies, while for Group A, the starter units were mostly interruptions. CONCLUSIONS: Compared to non-stuttering speakers, stuttering after TBI did not increase the number of clusters, but rather lengthened them. In speakers with neurogenic stuttering, the number and length of clusters were related to the manifestation of other communication deficits, not to the frequency of stuttering-like disfluencies. Still, SLD clusters occurred only in those people with neurogenic stuttering. These findings raise questions about the nature of both neurogenic stuttering and the dynamics of disfluency clustering.

Auditory-Perceptual Assessment of Fluency in Typical and Neurologically Disordered Speech.

Purpose: The aim of this study is to investigate how speech fluency in typical and atypical speech is perceptually assessed by speech-language pathologists (SLPs). Our research questions were as follows: (a) How do SLPs rate fluency in speakers with and without neurological communication disorders? (b) Do they differentiate the speaker groups? and (c) What features do they hear impairing speech fluency? Method: Ten SLPs specialized in neurological communication disorders volunteered as expert judges to rate 90 narrative speech samples on a Visual Analogue Scale (see Kempster, Gerratt, Verdolini Abbott, Barkmeier-Kraemer, & Hillman, 2009; p. 127). The samples-randomly mixed-were from 70 neurologically healthy speakers (the control group) and 20 speakers with traumatic brain injury, 10 of whom had neurogenic stuttering (designated as Clinical Groups A and B). Results: The fluency rates were higher for typical speakers than for speakers with traumatic brain injury; however, the agreement among the judges was higher for atypical fluency. Auditory-perceptual assessment of fluency was significantly impaired by the features of stuttering and something else but not by speech rate. Stuttering was also perceived in speakers not diagnosed as stutterers. A borderline between typical and atypical fluency was found. Conclusions: Speech fluency is a multifaceted phenomenon, and on the basis of this study, we suggest a more general approach to fluency and its deviations that will take into account, in addition to the motor and linguistic aspects of fluency, the metalinguistic component of expression as well. The results of this study indicate a need for further studies on the precise nature of borderline fluency and its different disfluencies.