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| 2. |
- Ternström, Sten, et al.
(författare)
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Cancellation of simulated environmental noise as a tool for measuring vocal performance during noise exposure
- 2002
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Ingår i: Journal of Voice. - 0892-1997 .- 1873-4588. ; 16:2, s. 195-206
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Tidskriftsartikel (refereegranskat)abstract
- It can be difficult for the voice clinician to observe or measure how a patient uses his voice in a noisy environment. We consider here a novel method for obtaining this information in the laboratory. Worksite noise and filtered white noise were reproduced over high-fidelity loudspeakers. In this noise, I I subjects read an instructional text of 1.5 to 2 minutes duration, as if addressing a group of people. Using channel estimation techniques, the site noise was suppressed from the recording, and the voice signal alone was recovered. The attainable noise rejection is limited only by the precision of the experimental setup, which includes the need for the subject to remain still so as not to perturb the estimated acoustic channel. This feasibility study, with 7 female and 4 male subjects, showed that small displacements of the speaker's body, even breathing, impose a practical limit on the attainable noise rejection. The noise rejection was typically 30 dB and maximally 40 dB down over the entire voice spectrum. Recordings thus processed were clean enough to permit voice analysis with the long-time average spectrum and the computerized phonetogram. The effects of site noise on voice sound pressure level, fundamental frequency, long-term average spectrum centroid, phonetogram area, and phonation time were much as expected, but with some interesting differences between females and males.
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| 3. |
- Ternström, Sten, et al.
(författare)
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Loud speech over noise : Some spectral attributes, with gender differences
- 2006
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Ingår i: Journal of the Acoustical Society of America. - : Acoustical Society of America (ASA). - 0001-4966 .- 1520-8524. ; 119:3, s. 1648-1665
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Tidskriftsartikel (refereegranskat)abstract
- In seeking an acoustic description of overloaded voice, simulated environmental noise was used to elicit loud speech. A total of 23 adults, 12 females and 11 males, read six passages of 90 s duration, over realistic noise presented over loudspeakers. The noise was canceled out, exposing the speech signal to analysis. Spectrum balance (SB) was defined as the level of the 2-6 kHz band relative to the 0.1-1 kHz band. SB averaged across many similar vowel segments became less negative with increasing sound pressure level (SPL), as described in the literature, but only at moderate SPL. At high SPL, SB exhibited a personal saturation point, above which the high-band level no longer increased faster than the overall SPL, or even stopped increasing altogether, on average at 90.3 dB WO cm) for females and 95.5 dB for males. Saturation occurred 6-8 dB; below the personal maximum SPL, regardless of gender. The loudest productions were often characterized by a relative increase in low-frequency energy, apparently in a sharpened first formant. This suggests a change of vocal strategy when the high spectrum can rise no further. The progression of SB with SPL was characteristically different for individual subjects.
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| 7. |
- Geneid, A., et al.
(författare)
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Long-term follow-up of patients with spasmodic dysphonia and improved voice despite discontinuation of treatment
- 2017
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Ingår i: Folia Phoniatrica et Logopaedica. - : S. Karger. - 1021-7762 .- 1421-9972. ; 68:3, s. 144-151
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To evaluate voice function in patients with adductor spasmodic dysphonia (AdSD) who discontinued botulinum toxin (BTX) treatment because they felt that their voice had improved sufficiently. Patients and Methods: Twenty-eight patients quit treatment in 2004, of whom 20 fulfilled the inclusion criteria for the study, with 3 subsequently excluded because of return of symptoms, leaving 17 patients (11 males, 6 females) included in this follow-up study. A questionnaire concerning current voice function and the Voice Handicap Index were completed. Audio-perceptual voice assessments were done by 3 listeners. The inter- and intrarater reliabilities were r > 0.80. Results: All patients had a subjectively good stable voice, but with differences in their audio-perceptual voice assessment scores. Based on the pre-/posttreatment auditory scores on the overall degree of AdSD, patients were divided into 2 subgroups showing more and less improvement, with 10 and 7 patients, respectively. The subgroup with more improvement had shorter duration from the onset of symptoms until the start of BTX treatment, and included 7 males compared to only 4 males in the subgroup with less improvement. Conclusion: It seems plausible that the symptoms of spasmodic dysphonia may decrease over time. Early intervention and male gender seem to be important factors for long-term reduction of the voice symptoms of AdSD.
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| 8. |
- Granqvist, Svante, et al.
(författare)
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Resonance tube phonation in water : High-speed imaging, electroglottographic and oral pressure observations of vocal fold vibrations - A pilot study
- 2015
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Ingår i: Logopedics, Phoniatrics, Vocology. - : Taylor & Francis. - 1401-5439 .- 1651-2022. ; 40:3, s. 113-121
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Tidskriftsartikel (refereegranskat)abstract
- Phonation into glass tubes (resonance tubes), keeping the free end of the tube in water, has been a frequently used voice therapy method in Finland and more recently also in other countries. The purpose of this exploratory study was to investigate what effects tube phonation with and without water has on the larynx. Two participants were included in the study. The methods used were high-speed imaging, electroglottographic observations of vocal fold vibrations, and measurements of oral pressure during tube phonation. Results showed that the fluctuation in the back pressure during tube phonation in water altered the vocal fold vibrations. In the high-speed imaging, effects were found in the open quotient and amplitude variation of the glottal opening. The open quotient increased with increasing water depth (from 2 cm to 6 cm). A modulation effect by the water bubbles on the vocal fold vibrations was seen both in the high-speed glottal area tracings and in the electroglottography signal. A second experiment revealed that the increased average oral pressure was largely determined by the water depth. The increased open quotient can possibly be explained by an increased abduction of the vocal folds and/or a reduced transglottal pressure. The back pressure of the bubbles also modulates glottal vibrations with a possible massage effect on the vocal folds. This effect and the well-defined average pressure increase due to the known water depth are different from those of other methods using a semi-occluded vocal tract.
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| 9. |
- Gustafsson, J., et al.
(författare)
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Motor-Learning-Based Adjustment of Ambulatory Feedback on Vocal Loudness for Patients With Parkinson's Disease
- 2016
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Ingår i: Journal of Voice. - : Elsevier. - 0892-1997 .- 1873-4588. ; 30:4, s. 407-415
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: To investigate how the direct biofeedback on vocal loudness administered with a portable voice accumulator (VoxLog) should be configured, to facilitate an optimal learning outcome for individuals with Parkinson's disease (PD), on the basis of principles of motor learning. Study Design: Methodologic development in an experimental study. Methods: The portable voice accumulator VoxLog was worn by 20 participants with PD during habitual speech during semistructured conversations. Six different biofeedback configurations were used, in random order, to study which configuration resulted in a feedback frequency closest to 20% as recommended on the basis of previous studies. Results: Activation of feedback when the wearer speaks below a threshold level of 3dB below the speaker's mean voice sound level in habitual speech combined with an activation time of 500ms resulted in a mean feedback frequency of 21.2%. Conclusions: Settings regarding threshold and activation time based on the results from this study are recommended to achieve an optimal learning outcome when administering biofeedback on vocal loudness for individuals with PD using portable voice accumulators.
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