Development of a Psychometric Measure of the Propensity to Consciously Control and Monitor Speech Production.

Purpose A speech-specific reinvestment scale (SSRS) is a psychometric measure of the propensity to consciously control and monitor speech production. This study develops and validates an SSRS as well as examines its relationship with speech performance with the moderating effects of trait social anxieties (i.e., social interaction anxiety, public speaking anxiety, and social phobia). Method Scale development involves the following stages: (a) initial item generation based on relevant literature, (b) item evaluation through cognitive interviews with 24 healthy respondents, (c) scale reliability and validity tests using cross-sectional survey data from 498 healthy respondents, and (d) test-retest reliability assessment using longitudinal survey data from 185 healthy respondents. Respondents' speech performance is quantified using speech examination scores. Hierarchical moderated regression analyses are conducted to examine the moderating effects of trait social anxieties. Results The validated SSRS comprises 35 items, which can be categorized into four subdimensions, namely, speech movement self-consciousness, public consciousness of speech content, speech manner, and speech movement. Results show that respondents with low trait social anxieties indicate a generally positive relationship between public consciousness of speech movement and speech performance, whereas respondents with high trait social anxieties exhibit a nonsignificant relationship. Conclusions SSRS offers a reliable and valid method for assessing the predisposition for conscious speech control and monitoring, which plays a role in speech performance and is moderated by an individual's level of trait social anxiety. SSRS is a potential assessment tool for speech-language pathologists to evaluate the impacts of conscious speech control and monitoring on individuals with speech impairment.

Effects of Error Experience on Learning to Lower Speech Nasalance Level.

Purpose This research aims to examine the effects of error experience when learning to speak with lowered nasalance level. Method A total of 45 typical speakers were instructed to learn to lower speech nasalance level in either an errorless (restricted possibility for committing errors) or an errorful (unrestricted possibility for committing errors) learning condition. The nasality level of the participants' speech was measured by a nasometer and quantified by nasalance scores (in percent). Errorless learners practiced producing speech with lowered nasalance level with a threshold nasalance score of 50% (the easiest target) at the beginning, which gradually decreased to a threshold of 10% (the most difficult target) at the end. The same set of threshold targets was presented to errorful learners, but in reverse order. Errors were defined by the proportion of speech, with a nasalance score exceeding the threshold. Retention and transfer tests were administered. Results Errorless learners displayed fewer errors and lower mean nasalance scores than errorful learners during the acquisition phase. Furthermore, errorless learners achieved lower mean nasalance scores than errorful learners in the retention and transfer tests. Conclusion These results suggest that errorless learning is more effective than errorful learning and that error experience has a detrimental effect on the acquisition of a novel speech motor task that requires minimization of the nasality level. Errorless learning may be a useful paradigm for the intervention and management of hypernasality in clinical settings where behavioral treatments are needed.

Spectral moment analysis of affricates produced by Mandarin-speaking pre-adolescents with repaired cleft palate.

OBJECTIVE: To explore the spectral differences in frication noise between aspirated and unaspirated affricates in typical Putonghua (standard Mandarin Chinese) pre-adolescent speakers, and to compare the spectral characteristics of affricate production between speakers with repaired cleft palate and their non-cleft peers. PARTICIPANTS AND INTERVENTION: Spectral moment analysis, a quantitative approach to capture the contour of speech spectra, was carried out on speech samples produced by two groups of speakers: (a) speakers with repaired cleft palate (n=14, mean age=11.7 years) and (b) typical speakers (n=10, mean age=11.0 years). RESULTS: Data from typical speakers showed that the unaspirated affricates had significantly higher first spectral moment (M1) than their aspirated counterparts. Compared with typical speakers, individuals with repaired cleft palate exhibited a lower first moment for the four affricates /ts, tʂ, tɕ(h), tɕ/. CONCLUSION: The results revealed important acoustical differences between aspirated and unaspirated affricates for typical speakers. The trend of spectral deviation may have contributed to the difficulty in producing unaspirated affricates found in Putonghua-speaking individuals with speech disorders related to cleft palate.

Consonant accuracy in Mandarin-speaking children with repaired cleft palate.

OBJECTIVE: To compare the consonant production of Chinese-speaking cleft palate children with perceived hypernasal resonance (PHR) after palatoplasty and those with perceived normal resonance (PNR), and to assess the possible influence of language on articulation. SETTING: Two hospital cleft lip and palate centers in mainland China. PARTICIPANTS: Thirty-one speakers were allocated into two groups based on perceptual judgment results of their resonance provided by three speech therapists: one group with PNR (n=20, average age=9.3 years), and another group with PHR (n=11, average age=8.3 years). All participants had no known hearing or cognitive deficits. INTERVENTION: Articulation was evaluated using two Mandarin Chinese assessment tools, the Putonghua Segmental Phonology Test and the Deep Test for Cleft Palate Speakers in Putonghua. Speaker consonant accuracy was evaluated by two experienced speech therapists. RESULTS: Compared to individuals with PNR, the PHR group exhibited more difficulties on production of unaspirated consonants, including/b/,/t/,/k/,/ts/,/tʂ/ and/tɕ/, than for aspirated consonants. CONCLUSION: The distinctive feature of aspiration in Mandarin phonology brought a language specific pattern to consonant production among those speakers with PHR after primary palatal closure.

Spectral features and perceptual judgment of place of affricate in Putonghua-speaking pre-adolescents with normal and cleft palate.

PURPOSE: The aim of the study was to examine the relationship between the spectral features and perceptual judgments of places of affricate in Putonghua (standard Mandarin Chinese), and to explore the possible contribution of different spectral moments on correct perception of place of articulation information by typical pre-adolescent speakers and those with cleft palate. METHOD: A total of 139 affricates produced by 10 normal pre-adolescent speakers and 14 speakers with repaired cleft palate (distorted articulation) were presented to 12 listeners tasked with making a judgment of the accuracy of place of articulation using a visual analog scale. RESULTS: Statistical analysis showed a significant relationship between the third spectral moment (L3) and listeners' perceptual judgment of typical alveolar and retroflex affricates. For productions by pre-adolescents with cleft palate, the first spectral moment (M1) was significantly correlated with listener perceptual scaling of retroflex affricates, but not for the alveolar affricates. CONCLUSION: Spectral features were associated with the perception of place of affricate in Putonghua. Different spectral moment characteristics might be used by listeners when perceiving speech from individuals with cleft palate.

Validity and Reliability of Visual Analog Scaling for Assessment of Hypernasality and Audible Nasal Emission in Children With Repaired Cleft Palate.

OBJECTIVE: To investigate the validity and reliability of multiple listener judgments of hypernasality and audible nasal emission, in children with repaired cleft palate, using visual analog scaling (VAS) and equal-appearing interval (EAI) scaling. DESIGN: Prospective comparative study of multiple listener ratings of hypernasality and audible nasal emission. SETTING: Multisite institutional. PARTICIPANTS: Five trained and experienced speech-language pathologist listeners from the Americleft Speech Project. MEASURES: Average VAS and EAI ratings of hypernasality and audible nasal emission/turbulence for 12 video-recorded speech samples from the Americleft Speech Project. Intrarater and interrater reliability was computed, as well as linear and polynomial models of best fit. RESULTS: Intrarater and interrater reliability was acceptable for both rating methods; however, reliability was higher for VAS as compared to EAI ratings. When VAS ratings were plotted against EAI ratings, results revealed a stronger curvilinear relationship. CONCLUSIONS: The results of this study provide additional evidence that alternate rating methods such as VAS may offer improved validity and reliability over EAI ratings of speech. VAS should be considered a viable method for rating hypernasality and nasal emission in speech in children with repaired cleft palate.

Problem-based learning (PBL) and speech-language pathology: a tutorial.

The aim of this tutorial is to provide an introduction to problem-based learning (PBL), particularly as applied to speech-language pathology (SLP) programs. The tutorial is aimed at the reader who is less familiar with this learning approach. Additionally, it serves as a framework for the articles that follow in this special issue on PBL programs in SLP and other clinical education programs. A brief history of PBL is provided and the rationale and context for this approach are identified. PBL is defined and differentiated from related educational approaches. Different models and variations of PBL are outlined. The key components of PBL are further illustrated using the tutorial cycle. Finally, we present one specific case of a PBL-based SLP program in detail. This tutorial will provide a deeper understanding of PBL for many higher educators in SLP. The strengths of this approach are outlined and the challenges are identified, particularly for those contemplating converting an existing "traditional" course or curriculum.

Concept map analysis in the assessment of speech-language pathology students' learning in a problem-based learning curriculum: a longitudinal study.

The aim of this study was to track students' critical thinking performance longitudinally through concept map analysis in a problem-based learning (PBL) curriculum. Concept map analysis has been employed in the assessment of students' critical thinking in medical education. Little is known concerning concept mapping (CM) in speech-language pathology (SLP) education. In this quantitative study, students in a 4-year SLP education program (N = 38) were followed until the completion of a fully-integrated PBL curriculum from Years 1 to 3. Students' concept maps were analyzed using a tool developed for this study, the Concept Map Assessment Profile (CMAP). There was an increase in concept map scores across the 3 years at the beginning of the academic year. The CM performance over the 3 years predicted 21.0% to 33.6% of variance in three measures of learning outcomes. The CMAP is a reliable measure, with strong inter-rater and intra-rater reliability (r = 0.85 and r = 0.96, respectively). In addition to its use as an assessment tool, the CMAP might be used to facilitate students' learning as feedback concerning strengths and weaknesses in the development of critical thinking can be provided.

Analogy instruction and speech performance under psychological stress.

To examine the efficacy of explicit and implicit forms of instruction for speech motor performance under conditions of psychological stress. In experiment 1, 20 participants were asked to deliver a formal presentation to validate the modified Trier Social Stress Test (TSST). In experiment 2, 40 participants were instructed explicitly by verbal explanation or implicitly by analogy to speak with minimum pitch variation and were subjected to psychological stress using the modified TSST. Acoustic correlates of pitch height (mean fundamental frequency) and pitch variation (standard deviation of fundamental frequency) significantly increased in experiment 1 when participants delivered a speech under modified TSST condition. In experiment 2, explicitly instructed participants were unable to maintain minimum pitch variation under psychological pressure caused by the modified TSST, whereas analogy-instructed participants maintained minimal pitch variation. The findings are consistent with existing evidence that analogy instructions may result in characteristics of implicit motor learning, such as greater stability of performance under pressure. Analogy instructions may therefore benefit speech motor performance and might provide a useful clinical tool for treatment of speech-disordered populations.

Performance of speech-language pathology students in problem-based learning tutorials and in clinical practice.

The purpose of the study was to identify if performance of speech-language pathology students in problem-based learning (PBL) tutorials could predict subsequent clinical performance evaluated through (a) a non-standardized, custom clinical evaluation form (HKU form) and (b) a standardized competency assessment for speech pathology developed in Australia (COMPASS®). Students' scores from PBL tutorial performance were correlated with scores in clinical placement on both the HKU form and the COMPASS. Significant correlations were found between students' PBL tutorial performance (reflective journals and participation in the tutorial process) and their clinical performance (treatment and interpersonal skills) on the HKU clinical evaluation form. Significant correlations were also found between (a) PBL tutorial performance (participation in the tutorial process) and their clinical performance (all generic and occupational competencies, and the overall score) on the COMPASS, (b) PBL tutorial performance (reading forms) and two occupational competencies on the COMPASS, (c) PBL tutorial performance (reflective journals) and four occupational competencies and the overall score on the COMPASS. The results highlighted the need for validating the assessment for the learning process in PBL tutorials with empirical evidence and the advantage of assessing clinical performance through COMPASS in Hong Kong. Tutors, clinical supervisors and students should be given clear behavioral descriptors for expected performance in PBL tutorials and clinical practice at different year levels.

Evaluation of speech errors in Putonghua speakers with cleft palate: a critical review of methodology issues.

Speech errors associated with cleft palate are well established for English and several other Indo-European languages. Few articles describing the speech of Putonghua (standard Mandarin Chinese) speakers with cleft palate have been published in English language journals. Although methodological guidelines have been published for the perceptual speech evaluation of individuals with cleft palate, there has been no critical review of methodological issues in studies of Putonghua speakers with cleft palate. A literature search was conducted to identify relevant studies published over the past 30 years in Chinese language journals. Only studies incorporating perceptual analysis of speech were included. Thirty-seven articles which met inclusion criteria were analyzed and coded on a number of methodological variables. Reliability was established by having all variables recoded for all studies. This critical review identified many methodological issues. These design flaws make it difficult to draw reliable conclusions about characteristic speech errors in this group of speakers. Specific recommendations are made to improve the reliability and validity of future studies, as well to facilitate cross-center comparisons.

Influence of analogy instruction for pitch variation on perceptual ratings of other speech parameters.

PURPOSE: Analogy is the similarity of different concepts on which a comparison can be based. Recently, an analogy of "waves at sea" was shown to be effective in modulating fundamental frequency (F0) variation. Perceptions of intonation were not examined, as the primary aim of the work was to determine whether analogy instruction had a negative impact on other parameters of the speech signal compared with explicit instruction. The purpose of this study was (a) to determine whether changes in the standard deviation of F0, acoustically, resulted in similar changes in the perception of pitch variability and (b) to determine the perceptual influence of analogy vs. explicit instructions on speech naturalness, loudness, and rate. METHOD: Ten speech-language pathologists were asked to listen to and rate pitch variation, speech naturalness, loudness, and rate for 74 Cantonese speech samples using a visual analogue scale, which allowed raters to indicate their subjective perceptions of each parameter. RESULTS: It is revealed that listeners perceived pitch variation to be greater and speech to be more natural in analogy-instructed, rather than explicitly instructed, speech. No differences were perceived for ratings of speech loudness or speech rate. CONCLUSION: It is concluded that analogy instruction has a less negative impact on the naturalness of speech than explicit instruction and may provide a better method by which to manipulate desired pitch variation.

Effects of practice schedules on speech motor learning.

The aim of this study was to evaluate the effects of various practice schedules on learning a novel speech task. Forty healthy Cantonese speakers were asked to learn to produce a Cantonese phrase with two target utterance durations (2500 and 3500 milliseconds). They were randomly assigned to one of four learning conditions, each completing a different practice schedule, namely Blocked only, Random only, Blocked-then-Random, and Random-then-Blocked. Two retention tests (one immediate and one delayed) and a transfer test were administered. The four groups of participants showed different patterns of learning, but achieved comparable levels of performance at the end of the acquisition phase. However, participants in the Blocked only condition were less able to differentiate the two target durations than those in the Random only condition during retention. Furthermore, participants who received both blocked and random practice were less adversely affected by the secondary task during the transfer test than those who received either blocked or random practice alone. These findings suggest that mixed practice schedules are more effective than either blocked or random practice, especially in transferring the acquired speech motor skills to a cognitively demanding situation. The results have clinical implications regarding optimal practice schedules for treatment intervention.

Effects of error experience when learning to simulate hypernasality.

PURPOSE: The purpose of this study was to evaluate the effects of error experience on the acquisition of hypernasal speech. METHOD: Twenty-eight healthy participants were asked to simulate hypernasality in either an errorless learning condition (in which the possibility for errors was limited) or an errorful learning condition (in which the possibility for errors was not limited). The nasality level of the participants' speech was measured with a nasometer and reflected by nasalance scores (in percentages). Errorless learners practiced producing hypernasal speech with a threshold nasalance score of 10% at the beginning, gradually increasing to a threshold of 50% at the end. The same set of threshold targets were presented to errorful learners but in a reversed order. Errors were defined by the proportion of speech with a nasalance score below the threshold. A retention test and a transfer test were administered. RESULTS: Relative to errorful learners, errorless learners displayed fewer errors and a higher mean nasalance score during acquisition. Furthermore, errorless learners outperformed errorful learners in both retention and transfer tests. CONCLUSION: The results suggest that errorless learning is more effective than errorful learning in acquiring a novel speech motor task that involves manipulation of the nasality level of speech.

The use of analogy in speech motor performance.

The acoustic correlates of pitch variation were examined in 40 participants who received analogy instructions or explicit instructions that required them to modulate their intonation during speech production. First, using focus group methodology, professional speech-language pathologists were asked to identify analogies that best described minimum pitch variation (monotone), moderate pitch variation (normal intonation), and maximum pitch variation (exaggerated intonation) in speech. The focus group established that an appropriate pitch variation metaphor may be related to imagery of "waves at sea", with minimum pitch variation represented by a flat calm sea, moderate pitch variation represented by a moderate sea, and maximum pitch variation represented by a choppy sea. Forty adult participants without speech impairments were asked to read aloud a standard paragraph using their habitual pitch variation (control condition). They were then allocated randomly to an analogy or an explicit instruction group and were asked to read aloud different paragraphs with minimum, moderate, or maximum pitch variations. Results revealed that acoustic correlates of pitch variation (standard deviation of fundamental frequency, SDF0) were not different for the control condition, or moderate and maximum pitch variation conditions in the two groups. However, the analogy instruction was significantly more effective than the explicit instruction for inducing minimum pitch variation. Analysis of participants in each group who showed higher than normal pitch variation in the control condition (>.5 SD above the group SDF0) revealed that the analogy instruction was more effective than the explicit instruction in the minimum variation condition. It was concluded that analogy instructions may be a useful tool in speech rehabilitation.

Perception of speech by individuals with Parkinson's disease: a review.

A few clinical reports and empirical studies have suggested a possible deficit in the perception of speech in individuals with Parkinson's disease. In this paper, these studies are reviewed in an attempt to support clinical anecdotal observations by relevant empirical research findings. The combined evidence suggests a possible deficit in patients' perception of their own speech loudness. Other research studies on the perception of speech in this population were reviewed, in a broader scope of the perception of emotional prosody. These studies confirm that Parkinson's disease specifically impairs patients' perception of verbal emotions. However, explanations of the nature and causes of this perceptual deficit are still limited. Future research directions are suggested.

Effect of LSVT on Lexical Tone in Speakers with Parkinson's Disease.

Lee Silverman Voice Treatment (LSVT) has well-documented treatment efficacy for individuals with hypokinetic dysarthria associated with Parkinson's disease (PD). Positive changes have been noted after treatment not only for vocal loudness but also for many other speech dimensions, including intonation (monotonicity). There have been few studies investigating the effect of LSVT on lexical tone which, like intonation, is controlled by variations in fundamental frequency. This study involved 12 Cantonese speakers with idiopathic PD who were enrolled in a standard LVST treatment protocol. Speech data were collected 3-4 days before treatment and 1 day after treatment. A wide variety of perceptual and acoustic variables were analyzed. The results showed significant improvements in loudness and intonation after treatment, but no significant changes in lexical tone. These results have theoretical implications for the relationship between tone and intonation and for models of the physiological control of fundamental frequency.

The perception of intonation questions and statements in Cantonese.

In tone languages there are potential conflicts in the perception of lexical tone and intonation, as both depend mainly on the differences in fundamental frequency (F0) patterns. The present study investigated the acoustic cues associated with the perception of sentences as questions or statements in Cantonese, as a function of the lexical tone in sentence final position. Cantonese listeners performed intonation identification tasks involving complete sentences, isolated final syllables, and sentences without the final syllable (carriers). Sensitivity (d' scores) were similar for complete sentences and final syllables but were significantly lower for carriers. Sensitivity was also affected by tone identity. These findings show that the perception of questions and statements relies primarily on the F0 characteristics of the final syllables (local F0 cues). A measure of response bias (c) provided evidence for a general bias toward the perception of statements. Logistic regression analyses showed that utterances were accurately classified as questions or statements by using average F0 and F0 interval. Average F0 of carriers (global F0 cue) was also found to be a reliable secondary cue. These findings suggest that the use of F0 cues for the perception of intonation question in tonal languages is likely to be language-specific.

Effects of Class III malocclusion on young male adults' vocal tract development: a pilot study.

PURPOSE: To compare the vocal tract configuration between male speakers with Class III malocclusion and their normally developing counterparts and to investigate the concomitant acoustic changes caused by the alterations in vocal tract configuration. PATIENTS AND METHODS: Eight young male patients with Class III malocclusion and 8 normally developing counterparts participated in this study. Acoustic reflection technology was used to measure vocal tract dimensions in the 2 groups. A continuous speech sample and 4 sustained vowels (/a/, /æ/, /i/, and /u/) were recorded from each participant to obtain the fundamental frequency and the first 3 formant frequencies (F1, F2, and F3). RESULTS: The results showed significantly greater oral length and oral volume for young male patients with Class III malocclusion than their cohorts. The F1 of vowel /u/ was found to be significantly higher in male patients with Class III malocclusion than their cohorts. The vowel space of the 4 recorded vowels was reduced and the F1-F2 formant map for /u/ was relatively more scattered in male patients with Class III malocclusion than in the control speakers. CONCLUSION: This study has provided preliminary information on the effects of Class III malocclusion on vocal tract configuration and concomitant acoustic changes in young male patients.

Studies of Chinese speakers with dysarthria: informing theoretical models.

Most theoretical models of dysarthria have been developed based on research using individuals speaking English or other Indo-European languages. Studies of individuals with dysarthria speaking other languages can allow investigation into the universality of such models, and the interplay between language-specific and language-universal aspects of dysarthria. In this article, studies of Cantonese- and Mandarin-Chinese speakers with dysarthria are reviewed. The studies focused on 2 groups of speakers: those with cerebral palsy and those with Parkinson's disease. Key findings are compared with similar studies of English speakers. Since Chinese is tonal in nature, the impact of dysarthria on lexical tone has received considerable attention in the literature. The relationship between tone [which involves fundamental frequency (F(0)) control at the syllable level] and intonation (involving F(0) control at the sentential level) has received more recent attention. Many findings for Chinese speakers with dysarthria support earlier findings for English speakers, thus affirming the language-universal aspect of dysarthria. However, certain differences, which can be attributed to the distinct phonologies of Cantonese and Mandarin, highlight the language-specific aspects of the condition.