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Speakers with severe dysarthria are known to have reduced range in prosody. Consistent control within that range, however, has largely been ignored. In earlier investigations speakers with severe dysarthria were able to control pitch and duration for sustained vowel production despite reduced flexibility of control (Patel, 1998). The present experiment examined whether 8 speakers with severe dysarthria due to cerebral palsy used prosodic parameters of pitch contour and syllable duration for phrase-level productions. Speakers with dysarthria (N = 8) produced 3-syllable phrases as questions and statements. Naive listeners (N = 48) classifed dysarthric productions as either questions or statements. Listeners were able to distinguish questions from statements with accuracy levels ranging from 81% to 98%. We were also interested in studying how dysarthric speakers marked the question-statement contrast. Prosodic features of pitch contour and syllable duration were systematically removed from the original recorded vocalizations to examine the salience of these features on listener classification. Removal of pitch contour cues dramatically reduced listener accuracy scores to almost chance performance. Listeners found pitch contour cues to be information-bearing cues in dysarthric vocalizations even though the range of frequency control in these speakers may be reduced. That speakers with dysarthria were able to exert sufficient control to signal the question-statement contrast has implications for diagnostic and intervention practices aimed to optimally exploit prosodic control for enhancing communication efficiency. KEY WORDS: dysarthria, prosody, question-statement, cerebral palsy, fundamental frequency, Individuals with severe dysarthria are unable to communicate effectively using speech alone. Many individuals, however, continue to use vocalizations when interacting with familiar communication partners (cf. Allaire, Gressard, Blackman, & [...]

This study compared changes in speech clarity as a function of speaking context. It is well documented that words produced in sentence contexts yield higher intelligibility than words in isolation for speakers with mild to moderate dysarthria. To tease apart the effect of speaker and listener variables, the current study aimed to quantify differences in word intelligibility by speaking task. Eighteen speakers with dysarthria produced a set of 25 words in isolation and within the context of a sentence. Eighteen listeners heard a randomized sample of the isolated productions, single words extracted from the sentences, and the full unaltered sentences. Listeners transcribed what they heard and rated their confidence. Words produced in isolation were just as intelligible as words produced in sentence context, both of which were more intelligible than extracted words. In other words, speakers reduced articulatory clarity in sentence production compared to isolated productions; listeners were able to cope with this reduction in clarity when they had access to contextual information but not when these cues were removed in the extracted condition. These findings are consistent with Lindblom's hypo–hyperarticulation theory in that adults with dysarthria appear to be modulating articulatory precision based on listener/task variables. This work has implications for clinical practice in that isolated word and sentence production tasks yielded equivalent intelligibility findings. Learning outcomes: Readers will recognize that speech intelligibility is influenced by speaker and listener variables and thus the choice of speaking and listening task may yield different results. Commonly held clinical belief is that sentence production tasks yield inflated intelligibility scores but we did not find that in this sample. Findings also indicate that speakers with dysarthria may modulate articulatory clarity in response to listener needs which should be considered in treatment planning. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop a picture description task for eliciting connected speech from children with motor speech disorders. The Park Play scene is a child-friendly picture description task aimed at augmenting current assessment protocols for childhood motor speech disorders. The design process included a literature review to: (1) establish optimal design features for child assessment, (2) identify a set of evidence-based speech targets specifically tailored to tax the motor speech system, and (3) enhance current assessment tools. To establish proof of concept, five children (ages 4;3-11;1) with dysarthria or childhood apraxia of speech were audio-recorded while describing the Park Play scene. Feedback from the feasibility test informed iterative design modifications. Descriptive, segmental, and prosodic analyses revealed the task was effective in eliciting desired targets in a connected speech sample, thereby yielding additional information beyond the syllables, words, and sentences generally elicited through imitation during the traditional motor speech examination. Further discussion includes approaches to adapt the task for a variety of clinical needs. [ABSTRACT FROM AUTHOR]

Background/Aims: To understand how reducing speaking rate alters prosodic contrasts in speakers with dysarthria (DYS) and healthy controls (HC). Methods: Seven male speakers with DYS (mean age = 34.9) and 7 age- and sex-matched HC (mean age = 36.9) produced identical phrases with affirmative (A), contrastive stress (CS) or question (Q) intonation at habitual and slow rate within a naturalistic game. Relative (word-to-word) changes in peak fundamental frequency (F0), intensity, and duration were compared across conditions, groups, and rates. Results: For some contrasts, rate reduction differentially affected the speaking groups, with HC exaggerating and speakers with DYS dampening some prosodic cues. Rate reduction diminished the Q contrast for both groups, with reduced peak F0 differences for HC and reduced word duration differences for HC and with DYS speakers. Slow rate also resulted in decreased lengthening of the final word for all three contrasts, thereby diminishing the Q contrast while exaggerating the CS and A contrasts. Conclusion: Although slow rate may improve segmental intelligibility, it may inadvertently dampen prosodic contrasts for some DYS speakers, thereby impacting communication effectiveness and naturalness. Implications for designing interventions that balance trade-offs between prosodic modulation and segmental clarity are discussed. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Purpose: A review of the salient characteristics of motor speech disorders and common assessment protocols revealed the need for a novel reading passage tailored specifically to differentiate between and among the dysarthrias (DYSs) and apraxia of speech (AOS). Method: "The Caterpillar" passage was designed to provide a contemporary, easily read, contextual speech sample with specific tasks (e.g., prosodic contrasts, words of increasing length and complexity) targeted to inform the assessment of motor speech disorders. Twenty-two adults, 15 with DYS or AOS and 7 healthy controls (HC), were recorded reading "The Caterpillar" passage to demonstrate its utility in examining motor speech performance. Conclusion: Analysis of performance across a subset of segmental and prosodic variables illustrated that "The Caterpillar" passage showed promise for extracting individual profiles of impairment that could augment current assessment protocols and inform treatment planning in motor speech disorders. [ABSTRACT FROM AUTHOR]

Purpose: In this study, the authors sought to understand acoustic and perceptual cues to contrastive stress in speakers with dysarthria (DYS) and healthy controls (HC). Method: The production experiment examined the ability of 12 DYS (9 male, 3 female; M = 39 years of age) and 12 age- and gender-matched HC (9 male, 3 female; M = 37.5 years of age) to signal contrastive stress within short sentences. Acoustic changes in fundamental frequency (F0), intensity, and duration were studied. The perceptual experiment explored whether 48 unfamiliar listeners (24 male, 24 female; M = 23.4 years of age) could identify the intended stress location in DYS and HC productions. Results: Although both speaker groups used all 3 prosodic cues, DYS relied more heavily on duration. Despite reduced F0 and intensity variation within DYS utterances, listeners were highly accurate at identifying both DYS (> 93%) and HC (> 97%) productions. Acoustic predictors of listener accuracy included heightened prosodic cues on stressed words along with marked decreases in these variables for neighboring nonstressed words. Conclusions: Speakers signaled contrastive stress using relative changes in one or more prosodic cue. Although individual speakers employed different cue combinations, listeners were highly adept at discerning the intended stress location. The communicative potential of prosody in speakers with congenital dysarthria is discussed. [ABSTRACT FROM AUTHOR]

Familiarity is thought to aid listeners in decoding disordered speech; however, as the speech signal degrades, the "familiarity advantage" becomes less beneficial. Despite highly unintelligible speech sound production, many children with dysarthria vocalize when interacting with familiar caregivers. Perhaps listeners can understand these vocalizations by cuing into prosodic consistencies in their child's productions. This paper examined whether familiarity influenced the identification of sustained vowels that varied in pitch, duration, and pitch-duration combinations, produced by 3 children with severe dysarthria due to cerebral palsy. Thirty-six listeners participated in the study. For each speaker, there were 2 familiar listeners (FAM), 5 experienced listeners (EXP), and 5 unfamiliar/inexperienced listeners (INX). Results indicated that familiarity did not impact identification of prosodic contrasts. In fact, all 3 listener groups were highly accurate in identifying duration, somewhat less successful at identifying pitch, and least accurate in identifying combinations of pitch and duration. Influences of speaker-listener variables on familiarity are discussed. [ABSTRACT FROM AUTHOR]

The article presents an overview of a study which examined the effectiveness of physiologic, behavioral or pragmatic approaches in the treatment of dysarthia. All the subjects in this study underwent initial screening and clinical assessment, speech-recognition-software training, therapy and dictation sessions and a post-therapy clinical assessment. Results show that the PowerSecretary speech-recognition software was effective for dictation.

Studies of prosodic control in severe dysarthria (DYS) have focused on differences between impaired and nonimpaired speech in terms of the range and variation of fundamental frequency (F0), intensity, and duration. Whether individuals with severe DYS can adequately signal prosodic contrasts and which acoustic cues they use to do so has received far less attention. This article focused on the question-statement contrast. In nonimpaired speech, this contrast is believed to be cued primarily by FO, although some researchers have argued that duration also plays a role. This study examined how 8 speakers with severe DYS due to cerebral palsy signaled the question-statement contrast for a set of 10 short phrases. An additional 8 healthy controls (HCs) produced the same set of phrases as questions and statements. To analyze the speech recordings, peak FO (F0peak), average FO (F0ave), slope of FO (F0slope), peak intensity (INTpeak), average intensity (INTave), slope of intensity (INTslope), and duration measures were calculated for each syllable (S1, S2, S3) within each phrase. Acoustic analyses revealed that speakers with DYS and HCs used FO, duration, and to a lesser degree, intensity cues to signal the contrast. Moreover, productions by speakers with DYS had longer and louder S3 for questions compared to productions by HCs, suggesting that speakers with DYS may have been compensating for their reduced ability to control FO by exploiting their residual control of loudness and duration. Data from a previous perceptual study (R. Patel, 2002b) with the same speakers with DYS were used to analyze the relationship between acoustic characteristics and listener perceptions of their productions. Logistic regression analysis revealed that S1_F0ave; S2_duration; and S3_duration, S3_F0peak, S3_F0slope, S3_InTave, and S3_Intslope were... [ABSTRACT FROM AUTHOR]

Augmentative and alternative communication (AAC) users with severe dysarthria may benefit greatly from using residual vocalizations to enhance communication efficiency and naturalness. Many individuals use their residual vocal control to gain attention, express emotions, and convey intentions to familiar care givers. This research was designed to test the hypothesis that speakers signal such information through the control of phonatory features such as pitch and duration, despite severe degradation of segmental speech sounds. The study examined whether eight speakers with severe dysarthria caused by cerebral palsy could control the pitch and duration of sustained vowel productions at three distinct levels. The results indicated that all speakers were able to consistently control sustained production of the vowel /a/ at three durations (short, medium, and long). Speakers were more variable, however, in their ability to control pitches (low, medium, and high). Seven of the eight speakers were able to produce at least two distinct pitches. The potential impact of harnessing residual phonatory control as an additional channel of input for AAC users with severe speech and motor impairment is discussed. [ABSTRACT FROM AUTHOR]