Aerodynamic characteristics associated with oesophageal and tracheoesophageal speech of Cantonese
International Journal of Speech-Language Pathology, 2011
The present study investigated the aerodynamic differences between standard oesophageal (SE) and ... more The present study investigated the aerodynamic differences between standard oesophageal (SE) and tracheoesophageal (TE) speech. Airflow and air pressure values below the pharyngoesophageal segment were obtained from 10 SE and 12 TE superior speakers of Cantonese. Airflow data were directly measured from sustained vowels, and sub-pharyngoesophageal segment pressure was estimated from /ip(h)ip(h)i/ syllables produced by the alaryngeal speakers. Results indicated that SE speech was associated with a lower rate of airflow and a higher pressure below the pharyngoesophageal segment than TE speech. SE and TE speakers exhibited an average airflow and sub-pharyngoesophageal segment pressure values of 70.50 mL/s and 134.15 mL/s, and 25.13 cm H(2)O and 22.61 cm H(2)O, respectively. Using the airflow and sub-pharyngoesophageal segment pressure, neoglottal resistance values were derived. The estimated neoglottal resistance was greater in SE speakers than in TE speakers. It is speculated that such difference in neoglottal resistance may be related to the use of different air reservoir mechanisms between SE and TE speakers. Such information will help speech-language pathologists design better speech therapy regimes for SE and TE speakers by understanding more about the difference between SE and TE phonation.
There is controversy about the efficacy of treating patients with laryngopharyngeal reflux (LPR) ... more There is controversy about the efficacy of treating patients with laryngopharyngeal reflux (LPR) using proton pump inhibitors (PPIs). We assessed the effects of high doses of the PPI rabeprazole in patients with LPR.Patients with LPR symptoms were assigned randomly to receive rabeprazole (20 mg, twice daily, n = 42) or placebo (n = 40) for 12 weeks. All patients completed symptom questionnaires; these provided demographic information and the reflux symptom index before, during, and 6 weeks after cessation of treatment. Videolaryngostroboscopy was used to document the laryngeal findings and determine the reflux finding score.Twenty-four patients (57.1%) in the rabeprazole group and 27 patients (67.5%) in the placebo group had pH-documented LPR. The total reflux symptom index score decreased significantly in the group given rabeprazole, compared with patients given placebo, at weeks 6 and 12, but not at week 18. However, there were no significant differences in reflux finding scores between the rabeprazole and placebo groups at any of the time points.Twelve weeks of treatment with rabeprazole (20 mg, twice daily) significantly improved reflux symptoms, compared with placebo, in patients with LPR. Relapse of symptoms was observed 6 weeks after stopping PPI therapy, indicating the requirement for longer treatment duration in patients with LPR.
Speech performance of adult cantonese-speaking laryngectomees using different types of alaryngeal phonation
Journal of Voice, 1997
The purpose of the present study was to compare the speech performance of four types of alaryngea... more The purpose of the present study was to compare the speech performance of four types of alaryngeal phonation-electrolaryngeal (EL), pneumatic artificial laryngeal (PA), tracheoesophageal (TE), and standard esophageal (SE) speech-by adult Cantonese-speaking laryngectomees. Subjective ratings of (1) voice quality, (2) articulation proficiency, (3) quietness of speech, (4) pitch variability, and (5) overall speech intelligibility were given by eight naive individuals who had no prior experience with any form of alaryngeal speech. Results indicated that SE and TE speech was perceived to be more hoarse than PA and EL speech. EL speech was associated with significantly less pitch variability, and PA speakers produced speech with the least amount of perceived noise. However, articulation proficiency and overall speech intelligibility were found to be comparable in all four types of alaryngeal speakers.
The present study attempted to investigate if alaryngeal speakers of Mandarin Chinese could diff ... more The present study attempted to investigate if alaryngeal speakers of Mandarin Chinese could diff erentially produce the four tone levels of Mandarin: high-level, mid-rising, falling-rising and high-falling, as perceived by native listeners. Syllables /ma/ and /ba/ produced at four diff erent tone levels by 8 normal laryngeal (NL), 7 standard esophageal (SE), and 8 electrolaryngeal (EL) speakers of Mandarin were perceived by 8 naïve listeners. Results from the listening experiments showed a higher percent correct identifi cation of tone for NL speech than SE and EL speech. Perceptual data showed diff erent patterns of tone confusion associated with the three types of speech. SE and EL speakers were not able to produce the four tone levels as accurately as were NL speakers. NL speakers achieved a near-perfect level of accuracy in signaling tonal contrasts. SE speakers produced the falling-rising and high-falling tones more accurately than high-level and mid-rising tones, but tonal confusions existed between mid-rising tone and fallingrising tone, and between high-level tone and high-falling tone. In EL phonation, highlevel tone was produced more accurately than the other tones which were often misidentifi ed as a high-level tone.
International Journal of Speech-Language Pathology, 2008
The present study quantified the amount of accent in English vowels produced by native adult Turk... more The present study quantified the amount of accent in English vowels produced by native adult Turkish speakers. Vowels that are present in both Turkish and English (close vowels) were compared with those that are present only in English (distant vowels). The first two formant frequencies (F1 and F2) were obtained from the 11 English monophthong vowels (/i, i, e, ε, æ, Λ, u, [Formula: see text], o, [Formula: see text], [Formula: see text]/) produced by 20 Turkish-accented English (TE) (10 males and 10 females) bilinguals and 20 native American English (AE) speakers. Euclidean distance (ED) was used to measure the separation between the corresponding TE and AE vowels. Perceptual experiment was also carried out to assess the amount of accent in the English produced by Turkish speakers as perceived by native monolingual English speakers. F1 and F2 values revealed that TE speakers generally were able to produce close and distant vowels comparably, with considerable amount of deviation from AE speakers. ED values for close and distant vowels were not significantly different. The amount of perceived accent indicated the precision of vowel production and was found to directly correlate with the acoustic findings.
Analyzing neoglottal vibration of Cantonese tracheoesophageal speech - A preliminary aerodynamic study using inverse-filtering
Folia Phoniatrica et Logopaedica, 2012
Despite the many studies on tracheoesophageal (TE) speech, the actual vibratory characteristics o... more Despite the many studies on tracheoesophageal (TE) speech, the actual vibratory characteristics of the neoglottis in TE speech are not known. The present study examined the neoglottal vibratory pattern of Cantonese TE speakers by comparison with the glottal waveform produced by laryngeal speakers. Eight superior TE and 8 laryngeal speakers of Cantonese participated in the study. All speakers were instructed to produce the vowels /i, œ, a, [see text], u/ 3 times, and both acoustic and aerodynamic signals were recorded. While the airflow signals were later inverse-filtered to obtain the neoglottal and glottal waveforms, the acoustic signals were analyzed to obtain vowel formants, which were used as inputs to inverse filtering. Aerodynamic parameters including open quotient (OQ), speed quotient (SQ), and area under the curve (AUC) were compared between TE and laryngeal speakers. - RESULTS revealed that TE speakers exhibited comparable OQ and AUC, but significantly reduced SQ when compared with laryngeal speakers. Both inverse-filtered airflow signals associated with TE and laryngeal speech of Cantonese appear to be triangular in shape, indicating the opening, closing and closed phases of the (neo)glottis. However, neoglottal waveforms are highly variable. Such variability and inconsistency in neoglottal waveforms might be related to the lack of complete control over the neoglottis in TE speakers.
International Journal of Speech-Language Pathology, 2011
The present study examined English sentence stress produced by native Cantonese speakers who were... more The present study examined English sentence stress produced by native Cantonese speakers who were speaking English as a second language (ESL). Cantonese ESL speakers' proficiency in English stress production as perceived by English-speaking listeners was also studied. Acoustical parameters associated with sentence stress including fundamental frequency (F0), vowel duration, and intensity were measured from the English sentences produced by 40 Cantonese ESL speakers. Data were compared with those obtained from 40 native speakers of American English. The speech samples were also judged by eight naïve listeners who were native speakers of American English for placement, degree, and naturalness of stress. Results showed that Cantonese ESL speakers were able to use F0, vowel duration, and intensity to differentiate sentence stress patterns. Yet, both female and male Cantonese ESL speakers exhibited consistently higher F0 in stressed words than English speakers. Overall, Cantonese ESL speakers were found to be proficient in using duration and intensity to signal sentence stress, in a way comparable with English speakers. In addition, F0 and intensity were found to correlate closely with perceptual judgement and the degree of stress with the naturalness of stress.
English vowels produced by Cantonese–English bilingual speakers
International Journal of Speech-Language Pathology, 2012
The present study attempted to test the postulate that sounds of a foreign language that are fami... more The present study attempted to test the postulate that sounds of a foreign language that are familiar can be produced with less accuracy than sounds that are new to second language (L2) learners. The first two formant frequencies (F1 and F2) were obtained from the 11 English monophthong vowels produced by 40 Cantonese-English (CE) bilingual and 40 native American English monolingual speakers. Based on F1 and F2, compact-diffuse (C-D) and grave-acute (G-A) values, and Euclidean Distance (ED) associated with the English vowels were evaluated and correlated with the perceived amount of accent present in the vowels. Results indicated that both male and female CE speakers exhibited different vowel spaces compared to their AE counterparts. While C-D and G-A indicated that acquisition of familiar and new vowels were not particularly different, ED values suggested better performance in CE speakers' productions of familiar vowels over new vowels. In conclusion, analyses based on spectral measurements obtained from the English vowel sounds produced by CE speakers did not provide favourable evidence to support the Speech Learning Model (SLM) proposed by Flege (1995) . Nevertheless, for both familiar and new sounds, English back vowels were found to be produced with greater inaccuracy than English front vowels.
2013 IEEE International Conference on Signal Processing, Communication and Computing (ICSPCC 2013), 2013
Injection laryngoplasty using hyaluronic acid for patients of unilateral vocal fold paralysis (UV... more Injection laryngoplasty using hyaluronic acid for patients of unilateral vocal fold paralysis (UVFP) is becoming more prevalent in Hong Kong. The present investigation explored the efficacy of the procedure by examining various acoustical measures. Both traditional perturbation analyses and nonlinear dynamical measures were used to assess the change in patients' voice quality between before, one month and three months after injection laryngoplasty. Jitter, shimmer, noise-toharmonic ratio (NHR), and nonlinear recurrence period density entropy (RPDE), detrended fluctuation analysis (DFA) and correlation dimension (D 2 ) were obtained from the sustained vowel /i/ produced by ten native Cantonese UVFP patients. Results showed that RPDE and D 2 were sensitive to improvement after injection laryngoplasty. The receiver operating characteristic area under curve analysis (ROC-AUC) was also used to demonstrate the diagnostic performance of these objective measures. High specificity of these four acoustic measures in distinguishing the voice quality before and after surgery was found, indicating that nonlinear dynamical analysis could be a supplemental tool to traditional acoustic analysis, and if combined, an effective monitoring tool for UVFP treatment.
The ability of Mandarin esophageal speakers to distinguish between aspirated and unaspirated stop... more The ability of Mandarin esophageal speakers to distinguish between aspirated and unaspirated stops, and to distinguish between different places of articulation of stops were examined. Aspirated and unaspirated voiceless stops produced by normal laryngeal (NL) and standard esophageal (SE) speakers were studied. VOT values of the five different stops (/p h , t h , k h , p, t/) of Mandarin followed by the vowel /a/ produced by NL and SE speakers were compared. Results from the perceptual experiment indicated that, while voiceless unaspirated stops produced by SE speakers were not signaled with a high level of accuracy, voiceless aspirated stops were perceived correctly by the listeners. Acoustic analysis showed that SE speakers consistently produced shorter VOT than NL speakers. Velar stops were associated with significantly longer VOT values than bilabial and alveolar stops in NL speakers. It was also found that, with the use of the PE segment, SE speakers were still able to use VOT to distinguish between aspirated and unaspirated stops, but they were unable to distinguish between bilabial, alveolar, and velar places of articulation.
Among the different alaryngeal speaker groups, naïve listeners tended to perceive the vowels prod... more Among the different alaryngeal speaker groups, naïve listeners tended to perceive the vowels produced by electrolaryngeal speakers more accurately.
2013 IEEE International Conference on Information and Automation (ICIA), 2013
The present project involved the development of a novel interactive speech training system based ... more The present project involved the development of a novel interactive speech training system based on virtual reality articulation and examination of the efficacy of the system for hearing impaired (HI) children. Twenty meaningful Mandarin words were presented to the HI children via a 3-D talking head during articulation training. Electromagnetic Articulography (EMA) and graphic transform technology were used to depict movements of various articulators. In addition, speech corpuses were organized in listening and speaking training modules of the system to help improve language skills of the HI children. Accuracy of virtual reality articulatory movement was evaluated through a series of experiments. Finally, a pilot test was performed to train two HI children using the system. Preliminary results showed improvement in speech production by the HI children, and the system was recognized as acceptable and interesting for children. It can be concluded that the training system is effective and valid in articulation training for HI children.
Pitch Control in Esophageal and Tracheoesophageal Speech of Cantonese
Folia Phoniatrica et Logopaedica, 2012
Previous studies of English-speaking esophageal (SE) and tracheoesophageal (TE) speakers revealed... more Previous studies of English-speaking esophageal (SE) and tracheoesophageal (TE) speakers revealed a significantly lower voice fundamental frequency (F0) than normal laryngeal (NL) speakers. Studies of SE and TE speakers of a tone language, however, indicated discrepant findings. Tonal SE and TE speakers could produce comparable or even higher F0 than NL speakers. The present study examined the F0 characteristics associated with speech and nonspeech tasks produced by Cantonese SE and TE speakers. Speech produced by 15 superior SE, 15 superior TE and 15 NL speakers was recorded while each was reading a short passage and performing a pitch scaling task. F0 values were calculated from the speech samples. SE speakers had higher average F0 in reading tasks than TE and NL speakers, while the NL speakers exhibited the highest average F0 values followed by SE and TE speakers during pitch scaling. In addition, pitch scaling (nonspeech) tasks were associated with higher average F0 than passage reading tasks regardless of speaker type. The findings point to the fact that, despite the use of the new sound source, SE and TE speakers were still able to change F0 for specific speech tasks.
Comparison of Vocal Characteristics of Future Professionals in Three Different University Majors
Page 1. 142 CONTEMPORARY ISSUES IN COMMUNICATION SCIENCE AND DISORDERS Volume 32 142150 Fa... more Page 1. 142 CONTEMPORARY ISSUES IN COMMUNICATION SCIENCE AND DISORDERS Volume 32 142150 Fall 2005 142 CONTEMPORARY ISSUES IN COMMUNICATION SCIENCE AND DISORDERS Volume ...
Aerodynamic characteristics associated with oesophageal and tracheoesophageal speech of Cantonese
International Journal of Speech-Language Pathology, 2011
The present study investigated the aerodynamic differences between standard oesophageal (SE) and ... more The present study investigated the aerodynamic differences between standard oesophageal (SE) and tracheoesophageal (TE) speech. Airflow and air pressure values below the pharyngoesophageal segment were obtained from 10 SE and 12 TE superior speakers of Cantonese. Airflow data were directly measured from sustained vowels, and sub-pharyngoesophageal segment pressure was estimated from /ip(h)ip(h)i/ syllables produced by the alaryngeal speakers. Results indicated that SE speech was associated with a lower rate of airflow and a higher pressure below the pharyngoesophageal segment than TE speech. SE and TE speakers exhibited an average airflow and sub-pharyngoesophageal segment pressure values of 70.50 mL/s and 134.15 mL/s, and 25.13 cm H(2)O and 22.61 cm H(2)O, respectively. Using the airflow and sub-pharyngoesophageal segment pressure, neoglottal resistance values were derived. The estimated neoglottal resistance was greater in SE speakers than in TE speakers. It is speculated that such difference in neoglottal resistance may be related to the use of different air reservoir mechanisms between SE and TE speakers. Such information will help speech-language pathologists design better speech therapy regimes for SE and TE speakers by understanding more about the difference between SE and TE phonation.
There is controversy about the efficacy of treating patients with laryngopharyngeal reflux (LPR) ... more There is controversy about the efficacy of treating patients with laryngopharyngeal reflux (LPR) using proton pump inhibitors (PPIs). We assessed the effects of high doses of the PPI rabeprazole in patients with LPR.Patients with LPR symptoms were assigned randomly to receive rabeprazole (20 mg, twice daily, n = 42) or placebo (n = 40) for 12 weeks. All patients completed symptom questionnaires; these provided demographic information and the reflux symptom index before, during, and 6 weeks after cessation of treatment. Videolaryngostroboscopy was used to document the laryngeal findings and determine the reflux finding score.Twenty-four patients (57.1%) in the rabeprazole group and 27 patients (67.5%) in the placebo group had pH-documented LPR. The total reflux symptom index score decreased significantly in the group given rabeprazole, compared with patients given placebo, at weeks 6 and 12, but not at week 18. However, there were no significant differences in reflux finding scores between the rabeprazole and placebo groups at any of the time points.Twelve weeks of treatment with rabeprazole (20 mg, twice daily) significantly improved reflux symptoms, compared with placebo, in patients with LPR. Relapse of symptoms was observed 6 weeks after stopping PPI therapy, indicating the requirement for longer treatment duration in patients with LPR.
Speech performance of adult cantonese-speaking laryngectomees using different types of alaryngeal phonation
Journal of Voice, 1997
The purpose of the present study was to compare the speech performance of four types of alaryngea... more The purpose of the present study was to compare the speech performance of four types of alaryngeal phonation-electrolaryngeal (EL), pneumatic artificial laryngeal (PA), tracheoesophageal (TE), and standard esophageal (SE) speech-by adult Cantonese-speaking laryngectomees. Subjective ratings of (1) voice quality, (2) articulation proficiency, (3) quietness of speech, (4) pitch variability, and (5) overall speech intelligibility were given by eight naive individuals who had no prior experience with any form of alaryngeal speech. Results indicated that SE and TE speech was perceived to be more hoarse than PA and EL speech. EL speech was associated with significantly less pitch variability, and PA speakers produced speech with the least amount of perceived noise. However, articulation proficiency and overall speech intelligibility were found to be comparable in all four types of alaryngeal speakers.
The present study attempted to investigate if alaryngeal speakers of Mandarin Chinese could diff ... more The present study attempted to investigate if alaryngeal speakers of Mandarin Chinese could diff erentially produce the four tone levels of Mandarin: high-level, mid-rising, falling-rising and high-falling, as perceived by native listeners. Syllables /ma/ and /ba/ produced at four diff erent tone levels by 8 normal laryngeal (NL), 7 standard esophageal (SE), and 8 electrolaryngeal (EL) speakers of Mandarin were perceived by 8 naïve listeners. Results from the listening experiments showed a higher percent correct identifi cation of tone for NL speech than SE and EL speech. Perceptual data showed diff erent patterns of tone confusion associated with the three types of speech. SE and EL speakers were not able to produce the four tone levels as accurately as were NL speakers. NL speakers achieved a near-perfect level of accuracy in signaling tonal contrasts. SE speakers produced the falling-rising and high-falling tones more accurately than high-level and mid-rising tones, but tonal confusions existed between mid-rising tone and fallingrising tone, and between high-level tone and high-falling tone. In EL phonation, highlevel tone was produced more accurately than the other tones which were often misidentifi ed as a high-level tone.
International Journal of Speech-Language Pathology, 2008
The present study quantified the amount of accent in English vowels produced by native adult Turk... more The present study quantified the amount of accent in English vowels produced by native adult Turkish speakers. Vowels that are present in both Turkish and English (close vowels) were compared with those that are present only in English (distant vowels). The first two formant frequencies (F1 and F2) were obtained from the 11 English monophthong vowels (/i, i, e, ε, æ, Λ, u, [Formula: see text], o, [Formula: see text], [Formula: see text]/) produced by 20 Turkish-accented English (TE) (10 males and 10 females) bilinguals and 20 native American English (AE) speakers. Euclidean distance (ED) was used to measure the separation between the corresponding TE and AE vowels. Perceptual experiment was also carried out to assess the amount of accent in the English produced by Turkish speakers as perceived by native monolingual English speakers. F1 and F2 values revealed that TE speakers generally were able to produce close and distant vowels comparably, with considerable amount of deviation from AE speakers. ED values for close and distant vowels were not significantly different. The amount of perceived accent indicated the precision of vowel production and was found to directly correlate with the acoustic findings.
Analyzing neoglottal vibration of Cantonese tracheoesophageal speech - A preliminary aerodynamic study using inverse-filtering
Folia Phoniatrica et Logopaedica, 2012
Despite the many studies on tracheoesophageal (TE) speech, the actual vibratory characteristics o... more Despite the many studies on tracheoesophageal (TE) speech, the actual vibratory characteristics of the neoglottis in TE speech are not known. The present study examined the neoglottal vibratory pattern of Cantonese TE speakers by comparison with the glottal waveform produced by laryngeal speakers. Eight superior TE and 8 laryngeal speakers of Cantonese participated in the study. All speakers were instructed to produce the vowels /i, œ, a, [see text], u/ 3 times, and both acoustic and aerodynamic signals were recorded. While the airflow signals were later inverse-filtered to obtain the neoglottal and glottal waveforms, the acoustic signals were analyzed to obtain vowel formants, which were used as inputs to inverse filtering. Aerodynamic parameters including open quotient (OQ), speed quotient (SQ), and area under the curve (AUC) were compared between TE and laryngeal speakers. - RESULTS revealed that TE speakers exhibited comparable OQ and AUC, but significantly reduced SQ when compared with laryngeal speakers. Both inverse-filtered airflow signals associated with TE and laryngeal speech of Cantonese appear to be triangular in shape, indicating the opening, closing and closed phases of the (neo)glottis. However, neoglottal waveforms are highly variable. Such variability and inconsistency in neoglottal waveforms might be related to the lack of complete control over the neoglottis in TE speakers.
International Journal of Speech-Language Pathology, 2011
The present study examined English sentence stress produced by native Cantonese speakers who were... more The present study examined English sentence stress produced by native Cantonese speakers who were speaking English as a second language (ESL). Cantonese ESL speakers' proficiency in English stress production as perceived by English-speaking listeners was also studied. Acoustical parameters associated with sentence stress including fundamental frequency (F0), vowel duration, and intensity were measured from the English sentences produced by 40 Cantonese ESL speakers. Data were compared with those obtained from 40 native speakers of American English. The speech samples were also judged by eight naïve listeners who were native speakers of American English for placement, degree, and naturalness of stress. Results showed that Cantonese ESL speakers were able to use F0, vowel duration, and intensity to differentiate sentence stress patterns. Yet, both female and male Cantonese ESL speakers exhibited consistently higher F0 in stressed words than English speakers. Overall, Cantonese ESL speakers were found to be proficient in using duration and intensity to signal sentence stress, in a way comparable with English speakers. In addition, F0 and intensity were found to correlate closely with perceptual judgement and the degree of stress with the naturalness of stress.
English vowels produced by Cantonese–English bilingual speakers
International Journal of Speech-Language Pathology, 2012
The present study attempted to test the postulate that sounds of a foreign language that are fami... more The present study attempted to test the postulate that sounds of a foreign language that are familiar can be produced with less accuracy than sounds that are new to second language (L2) learners. The first two formant frequencies (F1 and F2) were obtained from the 11 English monophthong vowels produced by 40 Cantonese-English (CE) bilingual and 40 native American English monolingual speakers. Based on F1 and F2, compact-diffuse (C-D) and grave-acute (G-A) values, and Euclidean Distance (ED) associated with the English vowels were evaluated and correlated with the perceived amount of accent present in the vowels. Results indicated that both male and female CE speakers exhibited different vowel spaces compared to their AE counterparts. While C-D and G-A indicated that acquisition of familiar and new vowels were not particularly different, ED values suggested better performance in CE speakers' productions of familiar vowels over new vowels. In conclusion, analyses based on spectral measurements obtained from the English vowel sounds produced by CE speakers did not provide favourable evidence to support the Speech Learning Model (SLM) proposed by Flege (1995) . Nevertheless, for both familiar and new sounds, English back vowels were found to be produced with greater inaccuracy than English front vowels.
2013 IEEE International Conference on Signal Processing, Communication and Computing (ICSPCC 2013), 2013
Injection laryngoplasty using hyaluronic acid for patients of unilateral vocal fold paralysis (UV... more Injection laryngoplasty using hyaluronic acid for patients of unilateral vocal fold paralysis (UVFP) is becoming more prevalent in Hong Kong. The present investigation explored the efficacy of the procedure by examining various acoustical measures. Both traditional perturbation analyses and nonlinear dynamical measures were used to assess the change in patients' voice quality between before, one month and three months after injection laryngoplasty. Jitter, shimmer, noise-toharmonic ratio (NHR), and nonlinear recurrence period density entropy (RPDE), detrended fluctuation analysis (DFA) and correlation dimension (D 2 ) were obtained from the sustained vowel /i/ produced by ten native Cantonese UVFP patients. Results showed that RPDE and D 2 were sensitive to improvement after injection laryngoplasty. The receiver operating characteristic area under curve analysis (ROC-AUC) was also used to demonstrate the diagnostic performance of these objective measures. High specificity of these four acoustic measures in distinguishing the voice quality before and after surgery was found, indicating that nonlinear dynamical analysis could be a supplemental tool to traditional acoustic analysis, and if combined, an effective monitoring tool for UVFP treatment.
The ability of Mandarin esophageal speakers to distinguish between aspirated and unaspirated stop... more The ability of Mandarin esophageal speakers to distinguish between aspirated and unaspirated stops, and to distinguish between different places of articulation of stops were examined. Aspirated and unaspirated voiceless stops produced by normal laryngeal (NL) and standard esophageal (SE) speakers were studied. VOT values of the five different stops (/p h , t h , k h , p, t/) of Mandarin followed by the vowel /a/ produced by NL and SE speakers were compared. Results from the perceptual experiment indicated that, while voiceless unaspirated stops produced by SE speakers were not signaled with a high level of accuracy, voiceless aspirated stops were perceived correctly by the listeners. Acoustic analysis showed that SE speakers consistently produced shorter VOT than NL speakers. Velar stops were associated with significantly longer VOT values than bilabial and alveolar stops in NL speakers. It was also found that, with the use of the PE segment, SE speakers were still able to use VOT to distinguish between aspirated and unaspirated stops, but they were unable to distinguish between bilabial, alveolar, and velar places of articulation.
Among the different alaryngeal speaker groups, naïve listeners tended to perceive the vowels prod... more Among the different alaryngeal speaker groups, naïve listeners tended to perceive the vowels produced by electrolaryngeal speakers more accurately.
2013 IEEE International Conference on Information and Automation (ICIA), 2013
The present project involved the development of a novel interactive speech training system based ... more The present project involved the development of a novel interactive speech training system based on virtual reality articulation and examination of the efficacy of the system for hearing impaired (HI) children. Twenty meaningful Mandarin words were presented to the HI children via a 3-D talking head during articulation training. Electromagnetic Articulography (EMA) and graphic transform technology were used to depict movements of various articulators. In addition, speech corpuses were organized in listening and speaking training modules of the system to help improve language skills of the HI children. Accuracy of virtual reality articulatory movement was evaluated through a series of experiments. Finally, a pilot test was performed to train two HI children using the system. Preliminary results showed improvement in speech production by the HI children, and the system was recognized as acceptable and interesting for children. It can be concluded that the training system is effective and valid in articulation training for HI children.
Pitch Control in Esophageal and Tracheoesophageal Speech of Cantonese
Folia Phoniatrica et Logopaedica, 2012
Previous studies of English-speaking esophageal (SE) and tracheoesophageal (TE) speakers revealed... more Previous studies of English-speaking esophageal (SE) and tracheoesophageal (TE) speakers revealed a significantly lower voice fundamental frequency (F0) than normal laryngeal (NL) speakers. Studies of SE and TE speakers of a tone language, however, indicated discrepant findings. Tonal SE and TE speakers could produce comparable or even higher F0 than NL speakers. The present study examined the F0 characteristics associated with speech and nonspeech tasks produced by Cantonese SE and TE speakers. Speech produced by 15 superior SE, 15 superior TE and 15 NL speakers was recorded while each was reading a short passage and performing a pitch scaling task. F0 values were calculated from the speech samples. SE speakers had higher average F0 in reading tasks than TE and NL speakers, while the NL speakers exhibited the highest average F0 values followed by SE and TE speakers during pitch scaling. In addition, pitch scaling (nonspeech) tasks were associated with higher average F0 than passage reading tasks regardless of speaker type. The findings point to the fact that, despite the use of the new sound source, SE and TE speakers were still able to change F0 for specific speech tasks.
Comparison of Vocal Characteristics of Future Professionals in Three Different University Majors
Page 1. 142 CONTEMPORARY ISSUES IN COMMUNICATION SCIENCE AND DISORDERS Volume 32 142150 Fa... more Page 1. 142 CONTEMPORARY ISSUES IN COMMUNICATION SCIENCE AND DISORDERS Volume 32 142150 Fall 2005 142 CONTEMPORARY ISSUES IN COMMUNICATION SCIENCE AND DISORDERS Volume ...
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