Acoustic variability in dysarthria : effects of articulation rate and its relationship with intelligibility

The purpose of this research is to investigate the effect of rate changes on measures of sentence-level acoustic variability in dysarthria, and evaluate possible relationships between acoustic variability measures and intelligibility in dysarthria

The Impact of Rate Reduction and Increased Loudness on Fundamental Frequency Characteristics in Dysarthria

OBJECTIVE: This study examined the extent to which articulatory rate reduction and increased loudness were associated with adjustments in utterance-level measures of fundamental frequency (F(0)) variability for speakers with dysarthria and healthy controls that have been shown to impact on intelligibility in previously published studies. More generally, the current study sought to compare and contrast how a slower-than-normal rate and increased vocal loudness impact on a variety of utterance-level F(0) characteristics for speakers with dysarthria and healthy controls. PATIENTS AND METHODS: Eleven speakers with Parkinson's disease, 15 speakers with multiple sclerosis, and 14 healthy control speakers were audio recorded while reading a passage in habitual, loud, and slow conditions. Magnitude production was used to elicit variations in rate and loudness. Acoustic measures of duration, intensity and F(0) were obtained. RESULTS AND CONCLUSIONS: For all speaker groups, a slower-than-normal articulatory rate and increased vocal loudness had distinct effects on F(0) relative to the habitual condition, including a tendency for measures of F(0) variation to be greater in the loud condition and reduced in the slow condition. These results suggest implications for the treatment of dysarthria

Relationship between acoustic measures and judgments of intelligibility in Parkinson\u27s disease: A within-speaker approach

This study investigated the acoustic basis of within-speaker, across-utterance variation in sentence intelligibility for 12 speakers with dysarthria secondary to Parkinson\u27s disease (PD). Acoustic measures were also obtained for 12 healthy controls for comparison to speakers with PD. Speakers read sentences using their typical speech style. Acoustic measures of speech rate, articulatory rate, fundamental frequency, sound pressure level and F2 interquartile range (F2 IQR) were obtained. A group of listeners judged sentence intelligibility using a computerized visual-analog scale. Relationships between judgments of intelligibility and acoustic measures were determined for individual speakers with PD. Relationships among acoustic measures were also quantified. Although considerable variability was noted, articulatory rate, fundamental frequency and F2 IQR were most frequently associated with within-speaker variation in sentence intelligibility. Results suggest that diversity among speakers with PD should be considered when interpreting results from group analyses

Acoustic and perceptual consequences of articulatory rate change in Parkinson disease

Zupan, BA ORCiD: 0000-0002-4603-333XThis study sought to characterize the relationship among voluntary rate modification, vocal tract acoustic output, and perceptual impressions of speech for individuals with idiopathic Parkinson disease (PD). Healthy control speakers were studied for comparison purposes. Four research questions were addressed: (1) How is rate modification evidenced in acoustic measures of segmental and global timing? (2) What is the impact of rate modification on measures of acoustic working space for select vowels and consonants? (3) What is the impact of rate modification on perceptual impressions of severity? (4) Are rate-induced changes in measures of acoustic working space related to perceptual impressions of severity? Speakers read the Farm Passage at habitual, slow, and fast rates. The vowels /i/, /œ/, /u/, and /A/ and the fricatives /s/ and /S/ were of interest. Acoustic measures included articulatory rate, segment durations, vowel formant frequencies, and first moment coefficients. Measures of acoustic working space for vowels and fricatives also were derived. The results indicated that temporal acoustic measures changed in the expected direction across rate conditions, with a tendency toward slightly faster rates for the PD group. In addition, the relative rate change for the Fast and Slow conditions compared to the Habitual condition was similar across groups. Rate did not strongly affect measures of acoustic working space for the PD group as a whole, but there was a tendency for slower rates to be associated with larger measures of acoustic working space. Finally, there was not a strong relationship between perceived severity and measures of acoustic working space across the rate continuum for either group. Rather, the relationship between perceived severity and measures of acoustic working space was such that the PD group exhibited smaller measures of acoustic working space and more severe perceptual estimates than the control speakers, irrespective of rate condition

Effects of speaking rate on variability of second formant frequency transitions in dysarthria

Introduction: This study examined the utility of multiple second formant (F2) slope metrics to capture differences in speech production for individuals with dysarthria and healthy controls as a function of speaking rate. In addition, the utility of F2 slope metrics for predicting severity of intelligibility impairment in dysarthria was examined. Methods: 23 speakers with Parkinson’s disease and mild to moderate hypokinetic dysarthria (HD), 9 speakers with various neurological diseases and mild to severe ataxic dysarthria (AD), and 26 age-matched healthy control speakers (CON) participated in a sentence repetition task. Sentences were produced at habitual, fast, and slow speaking rate. A variety of metrics were derived from the rising second formant (F2) transition portion of the diphthong /ai/. To obtain measures of intelligibility for the two clinical speaker groups, 15 undergraduate SLP students participated in a transcription experiment. Results: Significantly shallower slopes were found for the speakers with hypokinetic dysarthria compared to control speakers. Steeper F2 slopes were associated with increased speaking rate for all groups. Higher variability in F2 slope metrics was found for the speakers with ataxic dysarthria compared to the two other speaker groups. For both clinical speaker groups, there was a negative association between intelligibility and F2 slope variability metrics, indicating lower variability in speech production was associated with higher intelligibility. Discussion: F2 slope metrics were sensitive to dysarthria presence, dysarthria type and speaking rate. The current study provided evidence that the use of F2 slope variability measures has additional value to F2 slope averaged measures for predicting severity of intelligibility impairment in dysarthria

Intelligibility Across a Reading Passage: The Effect of Dysarthria and Cued Speaking Styles

Objective: Reading a passage out loud is a commonly used task in the perceptual assessment of dysarthria. The extent to which perceptual characteristics remain unchanged or stable over the time course of a passage is largely unknown. This study investigated crowdsourced visual analogue scale (VAS) judgments of intelligibility across a reading passage as a function of cued speaking styles commonly used in treatment to maximize intelligibility. Patients and Method: The Hunter passage was read aloud in habitual, slow, loud, and clear speaking styles by 16 speakers with Parkinson’s disease (PD), 30 speakers with multiple sclerosis (MS), and 32 control speakers. VAS judgments of intelligibility from three fragments representing the beginning, middle, and end of the reading passage were obtained from 540 crowdsourced online listeners. Results: Overall passage intelligibility was reduced for the two clinical groups relative to the control group. All speaker groups exhibited intelligibility variation across the reading passage, with trends of increased intelligibility toward the end of the reading passage. For control speakers and speakers with PD, patterns of intelligibility variation across passage reading did not differ with speaking style. For the MS group, intelligibility variation across the passage was dependent on speaking style. Conclusions: The presence of intelligibility variation within a reading passage warrants careful selection of speech materials in research and clinical practice. Results further indicate that the crowdsourced VAS rating paradigm is useful to document intelligibility in a reading passage for different cued speaking styles commonly used in treatment for dysarthria

Speaking Rate-Induced Acoustic Variabili@ in Parkinson's Disease

Abstract: The extent to which a model of the acoustic consequences of overlapping gestures accounted for speaking rate. induced variability in F2 trajectories for individuals with Parkinson's Disease(PD) and healthy controls was explored.F2 onset frequency was used as an acousticmeasureof overlappinggestures. The resultssuggestthat speakingratedid not consistently influence F2 onset frequency,and presumablygesture overlap,for either healthyspeakersor speakerswithPD INTRODUCTIO

Speech and pause characteristics in multiple sclerosis: A preliminary study of speakers with high and low neuropsychological test performance

This preliminary study investigated how cognitive-linguistic status in multiple sclerosis (MS) is reflected in two speech tasks (i.e. oral reading, narrative) that differ in cognitive-linguistic demand. Twenty individuals with MS were selected to comprise High and Low performance groups based on clinical tests of executive function and information processing speed and efficiency. Ten healthy controls were included for comparison. Speech samples were audio-recorded and measures of global speech timing were obtained. Results indicated predicted differences in global speech timing (i.e. speech rate and pause characteristics) for speech tasks differing in cognitive-linguistic demand, but the magnitude of these task-related differences was similar for all speaker groups. Findings suggest that assumptions concerning the cognitive-linguistic demands of reading aloud as compared to spontaneous speech may need to be re-considered for individuals with cognitive impairment. Qualitative trends suggest that additional studies investigating the association between cognitive-linguistic and speech motor variables in MS are warranted. © 2013 Informa UK Ltd

Separate and combined influence of cognitive impairment and dysarthria on functional communication in multiple sclerosis

Purpose: Dysarthria is a consequence of multiple sclerosis (MS) that can co-occur with cognitive impairment. Clinical management thus requires understanding the separate and combined effects of dysarthria and cognitive impairment on functional communication in MS. This study compared perceptual measures of intelligibility and speech severity that capture functional communication deficits for 4 operationally defined groups with MS. The relationship between communication participation and perceptual measures was also examined. Method: Forty-eight adults with MS and 12 healthy controls participated. Cognitive testing and dysarthria diagnosis determined group assignment: (a) MS with cognitive impairment (MSCI), (b) MS with a diagnosis of dysarthria and no cognitive impairment (MSDYS), (c) MS with dysarthria and cognitive impairment (MSDYS + CI), and (d) MS without dysarthria or cognitive impairment (MS). Sentence Intelligibility Test scores, scaled speech severity obtained from the “Grandfather Passage,” and Communication Participation Item Bank (CPIB) scores were analyzed. Results: Sentence Intelligibility Test scores approached 100% for all groups. Speech severity was greater for the MSDYS + CI and MSDYS groups versus controls. CPIB scores were greatest for the MSDYS + CI group and were not significantly correlated with either perceptual measure. Conclusions: The CPIB and speech severity were sensitive to aspects of communication problems for some groups with MS not reflected in a measure of sentence intelligibility. Findings suggest the importance of employing a variety of measures to capture functional communication problems experienced by persons with MS