• Phonetics and Speech Sciences
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• v.3 no.3
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• pp.57-62
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• 2011

Focused items in English sentences are usually accompanied by changes in acoustic manifestation. This paper investigates the acoustic characteristics of $H^*$ in English utterances produced by natives speakers of English and Korean learners of English. To obtain more reliable results, the changes of the acoustic feature values (F0, intensity, syllable duration) were normalized by a median value and a whole duration of each utterance. Acoustic values of sentences with no focused words were compared with those of sentences with focused words within each group (Americans vs. Koreans). Sentences with focused words were compared between the two groups, too. In the instances in which a significant Group x Focus Location (initial, middle and final of a sentence) interaction was obtained, further analysis testing the effect of Group on each Focus Location was conducted. The analysis revealed that Korean learners of English produced focused words with lower F0, lower intensity and shorter syllable duration than native speakers of English. However, the effect of intensity change caused by focus was not significant within each group. Further analysis examining the interaction of Group and Focus Location showed that the change in F0 produced by Korean group was significantly lower in the middle and the final positions of sentences than by American group. Implications for the intonation training were also discussed.

• Phonetics and Speech Sciences
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• v.3 no.3
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• pp.149-155
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• 2011

The purpose of the present study was to identify the differences in GRBAS scales between vocal sample types (sustained vowels and connected speech) for specific laryngeal conditions (vocal nodules, vocal polyps and vocal paralysis) and the relations between GRBAS scale and Shimmer value in each vocal sample type. In this study, the total of 60 voice samples of 30 patients (10 vocal nodules, 10 vocal polyps, 10 vocal paralysis) were examined and MDVP (Multi-dimensional Voice Program) was used to analyze Shimmer value. Three listeners rated two types of samples which were sorted randomly based on GRBAS scale. Three-way ANOVA, one-way ANOVA and paired t-test were used. The outcome of this study was as follow. 1) GRBAS scales varied in vocal sample types. Listeners tended to assess voices as better quality when they listened connected speech rather than sustained vowels. 2) G score of GRBAS and Shimmer were positively correlated with statistical significance. This results show that 1) vocal specialists should consider the sample types in evaluating the severity of voice problem and 2) G score could be a simple and clear method.

• Phonetics and Speech Sciences
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• v.3 no.3
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• pp.77-88
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• 2011

Foreign accent in second language production depends heavily on the transfer of features from the first language. This study examines acoustic variations in segments and suprasegments by native and nonnative speakers of English, searching for patterns of the transfer and plausible indexes of foreign accent in English. The acoustic variations are analyzed with recorded read speech by 20 native English speakers and 50 Korean learners of English, in terms of vowel formants, vowel duration, and syllabic variation induced by stress. The results show that the acoustic measurements of vowel formants and vowel and syllable durations display difference between native speakers and nonnative speakers. The difference is robust in the production of lax vowels, diphthongs, and stressed syllables, namely the English-specific features. L1 transfer on L2 specification is found both at the segmental levels and at the suprasegmental levels. The transfer levels measured as groups and individuals further show a continuum of divergence from the native-like target. Overall, the eldest group, students who are in the graduate schools, shows more native-like patterns, suggesting weaker foreign accent in English, whereas the high school students tend to involve larger deviation from the native speakers' patterns. Individual results show interdependence between segmental transfer and prosodic transfer, and correlation with self-reported proficiency levels. Additionally, experience factors in English such as length of English study and length of residence in English speaking countries are further discussed as factors to explain the acoustic variation.

• Phonetics and Speech Sciences
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• v.4 no.2
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• pp.115-120
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• 2012

This study sought to compare breath competence in three different utterance conditions when reading a passage aloud, making a spontaneous speech, and singing. We tested 15 normal females (ages averaging $24{\pm}4.4$) and measured breath competence through an objective, aero-mechanical instrument called PAS (Phonatory aerodynamic system, model 6600, KAY Electronics, Inc). Breathing sets of inspiration and expiration were measured by breath group number, breath group duration, and the ratio of inspiration to expiration. The results from this study led us to the following conclusion: The breath group number and the breath group duration showed no significant difference. However, the only variance that we could find was in the ratio of inspiration and expiration. In significantly different speech patterns, singing resulted in the most varied ratio of inspiration and expiration, followed by reading a text aloud, and spontaneous speech. The average frequency rates and maximum intensity levels varied with regards to varying utterance conditions. This thus shows that breath competence and phonation competence have a closely interrelated relationship.

• Phonetics and Speech Sciences
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• v.4 no.2
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• pp.105-114
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• 2012

This paper will discuss the difference between self assessment of voice disorders and the hearer voice assessment of a comparative group of normal subjects. The study was conducted on 25 voice disorder subjects and 32 hearers of a comparative group of normal subjects. The results are as follows. Firstly, in K-VHI and VHI-H, the hearers of the comparative group of normal subjects perceived more serious voice disorders than the voice disorder group in all sub-domains. Likewise, in K-VQOL and VRQOL-H, the hearers of the comparative group of normal subjects perceived more serious voice disorders than the voice disorder group in all sub-domains. Secondly, the hearer voice assessment of the comparative group of normal subjects showed no difference in gender regarding the perception of the severity of voice disorder issues. Thirdly, the hearer voice assessment of the comparative group of normal subjects states that in the emotional aspects of VHI-H, professional voice users perceive more serious voice disorders than others. Accordingly, in VRQOL-H, there was no difference in use of the voice between professionals and others.

• Phonetics and Speech Sciences
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• v.3 no.3
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• pp.125-132
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• 2011

Studies on the risk factors of voice disorders in Korean adults are rare. I evaluated the association between the duration of self-reported voice problem and voice disorders in Korean adults. Data were from the 2008 Korea National Health and Nutritional Examination Survey. Subjects were 3,135 people (1,310 men and 1,825 women) aged 19 years and older. Multi-nominal logistic regression analyses were used to examine the association between the duration of self-reported voice problem and voice disorders. The prevalence of self-reported voice problems was 5.9% among Korean adults. Adjusting for covariates (age, sex, education level, length of employment, tobacco consumption, alcohol consumption, thyroid disorders, pain and discomfort during the last two weeks), self-reported voice problems lasting longer than three weeks were independently associated with functional voice disorders (OR=5.30, 95% CI: 3.30-8.50) and organic voice disorders (OR=4.84, 95% CI: 1.82-12.89). Self-reported voice problems in the past three weeks were significantly associated with functional voice disorders (OR=3.64, 95% CI: 1.84-7.19), but not significantly associated with organic voice disorders. Self-reported voice problems are prevalent among adults. This study highlights that self-perception of a voice problem for more than three weeks is related to functional voice disorders and organic voice disorders.

• Phonetics and Speech Sciences
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• v.4 no.2
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• pp.127-134
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• 2012

The purpose of this study is to present evidence for a particular processing approach based on the language-specific characteristics of Korean. To compare individuals' sentence-comprehension abilities, this study measured the accuracy and reaction times (RT) of 12 aphasic patients (AP) and 12 normal controls (NC) during a sentence-picture matching task. Four versions of a sentence were constructed with the two types of voice (active/passive) and two types of word order (agent-first/patient-first). To examine the effects of increased processing demand, picture stimuli were manipulated in such a way that they appeared immediately after the sentence was presented. As expected, the AP group showed higher error rates and longer RT for all conditions than the NC group. Furthermore, Korean speakers with aphasia performed above a chance level in sentence comprehension, even with passive sentences. Aphasics understood sentences more quickly and accurately when they were given in the active voice and with agent-first order. The patterns of the NC group were similar. These results confirm that Korean adults with aphasia do not completely lose their knowledge of sentence comprehension. When the processing demand was increased by delaying the picture stimulus onset, the effect of increased processing demands on RT was more pronounced in the AP than in the NC group. These findings fit well with the idea that the computational system for interpreting sentences is intact in aphasics, but its ability is compromised when processing demands increase.

• Phonetics and Speech Sciences
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• v.4 no.2
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• pp.89-94
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• 2012

The aim of this study is to investigate the usefulness of the parameter CPP (cepstral peak prominence) and LTAS (long term average spectrum) band energy for an analysis of breathy voice with vocal fold paralysis. Thirty-four female subjects who have vocal paralysis after thyroidectomy participated in this study. According to the perceptual judgements by three speech pathologists and one phonetic scholar, subjects were divided into two groups: breathy voice group (n = 21) and non-breathy voice group (n = 13). Maximum sustained phonation task was measured for acoustic analysis. CPP-related (i.e. mean F0, mean CPP, and mean CPPs) and LTAS-related (i.e. minimum, maximum, and mean) parameters were used. Independent samples t-test was conducted. Regarding CPP, there are significant differences in mean CPP and mean CPPs between groups. The values of mean CPP and CPPs in the non-breathy voice group are higher than those in the breathy voice group. The CPP could be regarded as the useful parameter for breathy voice analysis in the clinic. When it comes to LTAS, energy from 0 to 2 kHz are significantly different between groups. The minimum value of non-breathy group is lower than that of breathy group, whereas the maximum value of non-breathy group is higher. The frequency band below 2 kHz seems to be related to breathy voice.

• Phonetics and Speech Sciences
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• v.3 no.3
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• pp.167-172
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• 2011

The purpose of this study was to examine the relationship between subjective and objective evaluation in speakers with voice disorders. Subjective evaluation indicates the self-reports of voice problems by dysphonic speakers. The relating protocol is the Voice Handicap Index (VHI) and the self-awareness index of voice problems (SAIVP-14). A total of 48 individuals with voice disorders replied to the questionnaire and participated in a voice assessment. Objective evaluations included the perceptual judgement of G grade in GRBAS, acoustic measurements (jitter, shimmer, NHR) by MDVP (CSL 4400), and aerodynamic measurements (MPT, MFR, psub) by PAS (Phonatory Aerodynamic System, KayPentax, USA). Pearson and Spearman correlations were used for the analysis. In the correlation with perceptual judgement (G grade) and VHI-Total, VHI-Physical, and SAIVP-14, there was a significant correlation, but the overall correlation was poor. NHR, jitter, and shimmer were significantly correlated with overall VHI and SAIVP-14. Specifically, the correlation with shimmer was stronger compared to the other measurements. In aerodynamic measures, MFR and MPT showed a significant correlation with VHI-Total, VHI-Emotional, and SAIVP-14, but their correlation was poor. The results of this study suggested that subjective evaluation of self voice problems is meaningfully correlated with objective evaluations, but more data in the multidimensional voice assessment should be collected and analyzed for the reliability and validity of the voice handicap questionnaire.

• Phonetics and Speech Sciences
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• v.4 no.2
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• pp.95-104
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• 2012

Thyroidectomy patients may have vocal paralysis or paresis, resulting in a breathy voice. The aim of this study was to investigate the aerodynamic and acoustic characteristics of a breathy voice in thyroidectomy patients. Thirty-five subjects who have vocal paralysis after thyroidectomy participated in this study. According to perceptual judgements by three speech pathologists and one phonetic scholar, subjects were divided into two groups: breathy voice group (n = 21) and non-breathy voice group (n = 14). Aerodynamic analysis was conducted by three tasks (Voicing Efficiency, Maximum Sustained Phonation, Vital Capacity) and acoustic analysis was measured during Maximum Sustained Phonation task. The breathy voice group had significantly higher subglottal pressure and more pathological voice characteristics than the non breathy voice group. Showing 94.1% classification accuracy in result logistic regression of aerodynamic analysis, the predictor parameters for breathiness were maximum sound pressure level, sound pressure level range, phonation time of Maximum Sustained Phonation task and Pitch range, peak air pressure, and mean peak air pressure of Voicing Efficiency task. Classification accuracy of acoustic logistic regression was 88.6%, and five frequency perturbation parameters were shown as predictors. Vocal paralysis creates air turbulence at the glottis. It fluctuates frequency-related parameters and increases aspiration in high frequency areas. These changes determine perceptual breathiness.