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result(s) for
"Speech Production"
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Vowel Acoustics in Parkinson's Disease and Multiple Sclerosis: Comparison of Clear, Loud, and Slow Speaking Conditions
2013
Purpose: The impact of clear speech, increased vocal intensity, and rate reduction on acoustic characteristics of vowels was compared in speakers with Parkinson's disease (PD), speakers with multiple sclerosis (MS), and healthy controls. Method: Speakers read sentences in habitual, clear, loud, and slow conditions. Variations in clarity, intensity, and rate were stimulated using magnitude production. Formant frequency values for peripheral and nonperipheral vowels were obtained at 20%, 50%, and 80% of vowel duration to derive static and dynamic acoustic measures. Intensity and duration measures were obtained. Results: Rate was maximally reduced in the slow condition, and vocal intensity was maximized in the loud condition. The clear condition also yielded a reduced articulatory rate and increased intensity, although less than for the slow or loud conditions. Overall, the clear condition had the most consistent impact on vowel spectral characteristics. Spectral and temporal distinctiveness for peripheral-nonperipheral vowel pairs was largely similar across conditions. Conclusions: Clear speech maximized peripheral and nonperipheral vowel space areas for speakers with PD and MS while also reducing rate and increasing vocal intensity. These results suggest that a speech style focused on increasing articulatory amplitude yields the most robust changes in vowel segmental articulation.
Journal Article
Taking Language Samples Home: Feasibility, Reliability, and Validity of Child Language Samples Conducted Remotely With Video Chat Versus In-Person
by
Manning, Brittany L.
,
Harpole, Alexandra
,
Harriott, Emily M.
in
Age differences
,
Auditory Evaluation
,
Best practice
2020
Purpose: There has been increased interest in using telepractice for involving more diverse children in research and clinical services, as well as when in-person assessment is challenging, such as during COVID-19. Little is known, however, about the feasibility, reliability, and validity of language samples when conducted via telepractice. Method: Child language samples from parent-child play were recorded either in person in the laboratory or via video chat at home, using parents' preferred commercially available software on their own device. Samples were transcribed and analyzed using Systematic Analysis of Language Transcripts software. Analyses compared measures between-subjects for 46 dyads who completed video chat language samples versus 16 who completed in-person samples; within-subjects analyses were conducted for a subset of 13 dyads who completed both types. Groups did not differ significantly on child age, sex, or socioeconomic status. Results: The number of usable samples and percent of utterances with intelligible audio signal did not differ significantly for in-person versus video chat language samples. Child speech and language characteristics (including mean length of utterance, type-token ratio, number of different words, grammatical errors/omissions, and child speech intelligibility) did not differ significantly between in-person and video chat methods. This was the case for between-group analyses and within-child comparisons. Furthermore, transcription reliability (conducted on a subset of samples) was high and did not differ between in-person and video chat methods. Conclusions: This study demonstrates that child language samples collected via video chat are largely comparable to in-person samples in terms of key speech and language measures. Best practices for maximizing data quality for using video chat language samples are provided.
Journal Article
Establishing Validity of the Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V)
2011
Purpose: The Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V) was developed to provide a protocol and form for clinicians to use when assessing the voice quality of adults with voice disorders (Kempster, Gerratt, Verdolini Abbott, Barkmeier-Kramer, & Hillman, 2009). This study examined the reliability and the empirical validity of the CAPE-V when used by experienced voice clinicians judging normal and disordered voices. Method: The validity of the CAPE-V was examined in 2 ways. First, we compared judgments made by 21 raters of 22 normal and 37 disordered voices using the CAPE-V and the GRBAS (grade, roughness, breathiness, asthenia, strain; see Hirano, 1981) scales. Second, we compared our raters' judgments of overall severity to a priori consensus judgments of severity for the 59 voices. Results: Intrarater reliability coefficients for the CAPE-V ranged from 0.82 for breathiness to 0.35 for strain; interrater reliability ranged from 0.76 for overall severity to 0.28 for pitch. Conclusions: Although both CAPE-V and GRBAS reliability coefficients varied across raters and parameters, this study reports slightly improved rater reliability using the CAPE-V to make perceptual judgments of voice quality in comparison to the GRBAS scale. The results provide evidence for the empirical (concurrent) validity of the CAPE-V. (Contains 8 tables.)
Journal Article
Differential Diagnosis of Children with Suspected Childhood Apraxia of Speech
by
Murray, Elizabeth
,
McCabe, Patricia
,
Heard, Robert
in
Accuracy
,
Apraxia
,
Apraxias - diagnosis
2015
Purpose: The gold standard for diagnosing childhood apraxia of speech (CAS) is expert judgment of perceptual features. The aim of this study was to identify a set of objective measures that differentiate CAS from other speech disorders. Method: Seventy-two children (4-12 years of age) diagnosed with suspected CAS by community speech-language pathologists were screened. Forty-seven participants underwent diagnostic assessment including presence or absence of perceptual CAS features. Twenty-eight children met two sets of diagnostic criteria for CAS (American Speech-Language-Hearing Association, 2007b; Shriberg, Potter, & Strand, 2009); another 4 met the CAS criteria with comorbidity. Fifteen were categorized as non-CAS with phonological impairment, submucous cleft, or dysarthria. Following this, 24 different measures from the diagnostic assessment were rated by blinded raters. Multivariate discriminant function analysis was used to identify the combination of measures that best predicted expert diagnoses. Results: The discriminant function analysis model, including syllable segregation, lexical stress matches, percentage phonemes correct from a polysyllabic picture-naming task, and articulatory accuracy on repetition of /p?t?k?/, reached 91% diagnostic accuracy against expert diagnosis. Conclusions: Polysyllabic production accuracy and an oral motor examination that includes diadochokinesis may be sufficient to reliably identify CAS and rule out structural abnormality or dysarthria. Testing with a larger unselected sample is required.
Journal Article
Speech Impairment in Down Syndrome: A Review
2013
This review summarizes research on disorders of speech production in Down syndrome (DS) for the purposes of informing clinical services and guiding future research.
Review of the literature was based on searches using MEDLINE, Google Scholar, PsycINFO, and HighWire Press, as well as consideration of reference lists in retrieved documents (including online sources). Search terms emphasized functions related to voice, articulation, phonology, prosody, fluency, and intelligibility.
The following conclusions pertain to four major areas of review: voice, speech sounds, fluency and prosody, and intelligibility. The first major area is voice. Although a number of studies have reported on vocal abnormalities in DS, major questions remain about the nature and frequency of the phonatory disorder. Results of perceptual and acoustic studies have been mixed, making it difficult to draw firm conclusions or even to identify sensitive measures for future study. The second major area is speech sounds. Articulatory and phonological studies show that speech patterns in DS are a combination of delayed development and errors not seen in typical development. Delayed (i.e., developmental) and disordered (i.e., nondevelopmental) patterns are evident by the age of about 3 years, although DS-related abnormalities possibly appear earlier, even in infant babbling. The third major area is fluency and prosody. Stuttering and/or cluttering occur in DS at rates of 10%-45%, compared with about 1% in the general population. Research also points to significant disturbances in prosody. The fourth major area is intelligibility. Studies consistently show marked limitations in this area, but only recently has the research gone beyond simple rating scales.
Journal Article
Objective Acoustic Quantification of Perceived Voice Tremor Severity
2019
Purpose: This study compared auditory-perceptual measures of presence/absence and severity of vocal tremor to acoustic markers of vocal tremor. The validity (both concurrent and diagnostic) of various acoustic markers of vocal tremor was also assessed. Method: Fifty-six midvowel sustained [a:] recordings were selected to yield a representative convenience sample of vocal tremor. After training with 10 synthesized samples, 4 female audiologists rated these samples on \"voice tremor severity\" on a continuous 10-cm scale. Afterward, 15 randomly selected recordings were presented a 2nd time for intrarater reliability assessment. Customized audio signal processing in Praat yielded 12 acoustic measures of rate, extent and perturbation of fundamental frequency (f[subscript 0]), and intensity level (IL) modulation. Enter-type multiple linear regression analysis was applied to weight and combine these acoustic variables into an acoustic model of vocal tremor severity. Results: After removing the vocal tremor severity ratings of 1 of the audiologists because of insufficient intra- and interrater reliability, mean single-measures consistency-type intraclass correlation coefficients equaled 0.83 within raters and 0.72 between raters. Correlation between mean ratings and the 12 acoustic markers ranged from 0.76 for median extent of f[subscript 0] modulation to 0.11 for rate of IL modulation. Correlation between mean ratings and the acoustic model was 0.89. Analysis of this model's receiver operating characteristics yielded an area under receiver operating characteristic curve of 0.93, denoting sensitivity of 0.87 and specificity of 0.91. Conclusions: This study demonstrated that auditory-perceptual ratings of vocal tremor severity are guided primarily by f[subscript 0] and IL modulation extent, less by modulation perturbation, and least by modulation rate. The acoustic model covering all these modulation properties yielded acceptable results in terms of both concurrent and diagnostic validity. However, external cross-validation of this model is warranted before applying it in clinical voice/speech assessment.
Journal Article
Real-Time Control of an Articulatory-Based Speech Synthesizer for Brain Computer Interfaces
by
Savariaux, Christophe
,
Yvert, Blaise
,
Bocquelet, Florent
in
Acoustics
,
Aphasia
,
Biofeedback, Psychology - instrumentation
2016
Restoring natural speech in paralyzed and aphasic people could be achieved using a Brain-Computer Interface (BCI) controlling a speech synthesizer in real-time. To reach this goal, a prerequisite is to develop a speech synthesizer producing intelligible speech in real-time with a reasonable number of control parameters. We present here an articulatory-based speech synthesizer that can be controlled in real-time for future BCI applications. This synthesizer converts movements of the main speech articulators (tongue, jaw, velum, and lips) into intelligible speech. The articulatory-to-acoustic mapping is performed using a deep neural network (DNN) trained on electromagnetic articulography (EMA) data recorded on a reference speaker synchronously with the produced speech signal. This DNN is then used in both offline and online modes to map the position of sensors glued on different speech articulators into acoustic parameters that are further converted into an audio signal using a vocoder. In offline mode, highly intelligible speech could be obtained as assessed by perceptual evaluation performed by 12 listeners. Then, to anticipate future BCI applications, we further assessed the real-time control of the synthesizer by both the reference speaker and new speakers, in a closed-loop paradigm using EMA data recorded in real time. A short calibration period was used to compensate for differences in sensor positions and articulatory differences between new speakers and the reference speaker. We found that real-time synthesis of vowels and consonants was possible with good intelligibility. In conclusion, these results open to future speech BCI applications using such articulatory-based speech synthesizer.
Journal Article
Tutorial and Guidelines on Measurement of Sound Pressure Level in Voice and Speech
2018
Purpose: Sound pressure level (SPL) measurement of voice and speech is often considered a trivial matter, but the measured levels are often reported incorrectly or incompletely, making them difficult to compare among various studies. This article aims at explaining the fundamental principles behind these measurements and providing guidelines to improve their accuracy and reproducibility. Method: Basic information is put together from standards, technical, voice and speech literature, and practical experience of the authors and is explained for nontechnical readers. Results: Variation of SPL with distance, sound level meters and their accuracy, frequency and time weightings, and background noise topics are reviewed. Several calibration procedures for SPL measurements are described for stand-mounted and head-mounted microphones. Conclusions: SPL of voice and speech should be reported together with the mouth-to-microphone distance so that the levels can be related to vocal power. Sound level measurement settings (i.e., frequency weighting and time weighting/averaging) should always be specified. Classified sound level meters should be used to assure measurement accuracy. Head-mounted microphones placed at the proximity of the mouth improve signal-to-noise ratio and can be taken advantage of for voice SPL measurements when calibrated. Background noise levels should be reported besides the sound levels of voice and speech.
Journal Article
Clear Speech Variants: An Acoustic Study in Parkinson's Disease
2016
Purpose: The authors investigated how different variants of clear speech affect segmental and suprasegmental acoustic measures of speech in speakers with Parkinson's disease and a healthy control group. Method: A total of 14 participants with Parkinson's disease and 14 control participants served as speakers. Each speaker produced 18 different sentences selected from the Sentence Intelligibility Test (Yorkston & Beukelman, 1996). All speakers produced stimuli in 4 speaking conditions (habitual, clear, overenunciate, and hearing impaired). Segmental acoustic measures included vowel space area and first moment (M1) coefficient difference measures for consonant pairs. Second formant slope of diphthongs and measures of vowel and fricative durations were also obtained. Suprasegmental measures included fundamental frequency, sound pressure level, and articulation rate. Results: For the majority of adjustments, all variants of clear speech instruction differed from the habitual condition. The overenunciate condition elicited the greatest magnitude of change for segmental measures (vowel space area, vowel durations) and the slowest articulation rates. The hearing impaired condition elicited the greatest fricative durations and suprasegmental adjustments (fundamental frequency, sound pressure level). Conclusions: Findings have implications for a model of speech production for healthy speakers as well as for speakers with dysarthria. Findings also suggest that particular clear speech instructions may target distinct speech subsystems.
Journal Article
A Framework of Motoric Complexity: An Investigation in Children With Typical and Impaired Speech Development
2020
Introduction: The current work presents a framework of motoric complexity where stimuli differ according to movement elements across a sound sequence (i.e., consonant transitions and vowel direction). This framework was then examined in children with childhood apraxia of speech (CAS), other speech sound disorders (SSDs), and typical development (TD). Method: Twenty-four children (CAS, n = 8; SSD, n = 8; TD, n = 8), 5-6 years of age, participated in this study. The children produced words that varied in motoric complexity while transcription, acoustic, and kinematic data were collected. Multidimensional analyses were conducted to examine speech production accuracy, speech motor variability, and temporal control. Results: Analyses revealed poorer accuracy, longer movement duration, and greater speech motor variability in children with CAS than TD (across all measures) and other SSDs (accuracy and variability). All children demonstrated greater speech motor variability and longer duration as movement demands increased within the framework of motoric complexity. Diagnostic grouping did not mediate performance on this task. Conclusions: Results of this study are believed to reveal gradations of complexity with increasing movement demands, thereby supporting the proposed framework of motoric complexity. This work also supports the importance of considering motoric properties of sound sequences when evaluating speech production skills and designing experimental and treatment stimuli.
Journal Article