Respiratory kinematics during vocalization and nonspeech respiration in children from 9 to 48 months.
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The development of respiratory drive for vocalization was studied by observing chest wall kinematics longitudinally in 4 typically developing children from the age of 9 to 48 months. Measurements of the relative contribution of rib cage and abdominal movement during vocalization (i.e., babbling and true words) and rest breathing were obtained every 3 months using respiratory plethysmography (Respitrace). Extending earlier findings in 15-month-olds, 2 methods of analysis of rib cage and abdominal movement were used: (a). a dynamic index of the strength of coupling between the rib cage and abdomen, and (b). a classification scheme describing the moment-by-moment changes in each of the 2 components (C. A. Moore, T. J. Caulfield, and J. R. Green, 2001). The developmental course of relative chest wall kinematics differed between vocalization and rest breathing. The coupling of rib cage and abdomen during vocalization weakened significantly with development, whereas it remained consistently strong for rest breathing throughout the observed period. The developmental changes in frequency of occurrence of relative moment-by-moment changes varied across movement type. The results support previous findings that speech breathing is distinct from rest breathing based on the relative contributions of the rib cage and abdomen. Longitudinal changes are likely responsive to anatomic development, including changes to rib cage shape and compliance. (+info)
Compensation for pitch-shifted auditory feedback during the production of Mandarin tone sequences.
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Recent research has found that while speaking, subjects react to perturbations in pitch of voice auditory feedback by changing their voice fundamental frequency (F0) to compensate for the perceived pitch-shift. The long response latencies (150-200 ms) suggest they may be too slow to assist in on-line control of the local pitch contour patterns associated with lexical tones on a syllable-to-syllable basis. In the present study, we introduced pitch-shifted auditory feedback to native speakers of Mandarin Chinese while they produced disyllabic sequences /ma ma/ with different tonal combinations at a natural speaking rate. Voice F0 response latencies (100-150 ms) to the pitch perturbations were shorter than syllable durations reported elsewhere. Response magnitudes increased from 50 cents during static tone to 85 cents during dynamic tone productions. Response latencies and peak times decreased in phrases involving a dynamic change in F0. The larger response magnitudes and shorter latency and peak times in tasks requiring accurate, dynamic control of F0, indicate this automatic system for regulation of voice F0 may be task-dependent. These findings suggest that auditory feedback may be used to help regulate voice F0 during production of bi-tonal Mandarin phrases. (+info)
Specially programmed respiratory muscle training for singers by using respiratory muscle training device (Ultrabreathe).
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Respiratory muscle training is one of the major methods for enhancing the vocal function. Singers who must use their voice most frequently are well aware of the importance of respiration. However, most of them do not know precisely how to exercise their abdominal respiration. Using a respiratory training device, singers are expected to gain more efficiency in their vocal enhancement. The aim of the study was to examine the pulmonary function, the maximum inspiratory pressure (MIP) and the maximum expiratory pressure (MEP), and the maximum phonation time (MPT) in five female voice-majors students after undergoing specially programmed respiratory muscle training for 2 months. All the voice-majors had an average of 4.8 years of formal classical voice training. A respiratory muscle training device (Ultrabreathe), Tangent health Care Inc., England) was used to train the respiratory muscle. None of the pulmonary function test variables had changed after respiratory muscle training. However, the MIP, MEP, and MPT were significantly increased higher after the respiratory muscle training. This suggests that the specially programmed respiratory muscle training can improve the respiratory muscle strength and vocal function without increasing the pulmonary function. (+info)
Temporal nitric oxide dynamics in the paranasal sinuses during humming.
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In this study, the temporal shape of voice-induced nitric oxide (NO) signals in exhaled air has been investigated in eight healthy individuals by means of laser magnetic resonance spectroscopy. The results of the experimental part have been compared with calculated signals obtained by using a simple one-compartment model of the paranasal sinuses. In the experimental part, a rapidly increasing NO concentration has been found when the subjects started humming. After reaching a maximum, the emission starts to decrease with the shape of an exponential decay and finally reaches a constant level. The time constant of this decay (NO washout) is 3.0 +/- 1.2 s. The peak height of the NO emission during humming increases when the time between two humming processes increases. When no voice-induced NO emission takes place, the NO concentration in the paranasal sinuses rebuilds again to a maximum concentration. The typical time constant for the NO recovery is 4.5 +/- 3.2 min. A three-compartment model defining exactly the geometry and anatomy of the paranasal sinuses has been developed that is based on three main assumptions of the NO dynamics: 1) constant NO production of the epithelium in the sinuses; 2) the rate of the chemical reaction of NO with the epithelium of the paranasal sinuses is proportional to the NO concentration; and 3) the emission of NO from the sinuses (volume/s) is proportional to the NO concentration. It is shown that the three-compartment model under the experimental conditions can be reduced to a one-compartment model, which describes the complete temporal behavior of the NO exchange. (+info)
Persistent swallowing and voice problems after anterior cervical discectomy and fusion with allograft and plating: a 5- to 11-year follow-up study.
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Anterior cervical discectomy and fusion is commonly performed for cervical disc disease. Most studies report that swallowing and voice problems after such surgeries tend to resolve with time and are often of minor significance except in the rare cases of recurrent laryngeal nerve palsies. A retrospective review was performed on patients who had anterior cervical discectomy and fusion by a single surgeon more than 5 years prior, to determine the persistence of swallowing and voice problems in them. Seventy-four patients who had anterior cervical discectomy and fusion with allograft and plating an average of 7.2 years prior responded to an invitation to return for a follow-up clinical review. Emphasis was placed on the symptoms of dysphagia and dysphonia, as related to the index surgery. At final review, persistent dysphagia was present in 26 patients (35.1%). This occurred more frequently in females and in younger patients. Dysphonia at final review persisted in 14 patients (18.9%). This also occurred more commonly in females and in patients in whom possible non-union is present in at least one of the levels operated upon. Problems with singing were present in 16 patients (21.6%) postoperatively, occurring more frequently if the C3/4 disc was included in the surgery and in patients who have had a greater total number of anterior cervical surgeries at the time of review. Dysphonia and dysphagia are persistent problems in a significant proportion of patients, even beyond 5 years after anterior cervical spine surgery. (+info)
The emergence of mature gestural patterns in the production of voiceless and voiced word-final stops.
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The organization of gestures was examined in children's and adults' samples of consonant-vowel-stop words differing in stop voicing. Children (5 and 7 years old) and adults produced words from five voiceless/voiced pairs, five times each in isolation and in sentences. Acoustic measurements were made of vocalic duration, and of the first and second formants at syllable center and voicing offset. The predicted acoustic correlates of syllable-final voicing were observed across speakers: vocalic segments were shorter and first formants were higher in words with voiceless, rather than voiced, final stops. In addition, the second formant was found to differ depending on the voicing of the final stop for all speakers. It was concluded that by 5 years of age children produce words ending in stops with the same overall gestural organization as adults. However, some age-related differences were observed for jaw gestures, and variability for all measures was greater for children than for adults. These results suggest that children are still refining their organization of articulatory gestures past the age of 7 years. Finally, context effects (isolation or sentence) showed that the acoustic correlates of syllable-final voicing are attenuated when words are produced in sentences, rather than in isolation. (+info)
Changes to respiratory mechanisms during speech as a result of different cues to increase loudness.
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The purpose of the present study was to determine whether different cues to increase loudness in speech result in different internal targets (or goals) for respiratory movement and whether the neural control of the respiratory system is sensitive to changes in the speaker's internal loudness target. This study examined respiratory mechanisms during speech in 30 young adults at comfortable level and increased loudness levels. Increased loudness was elicited using three methods: asking subjects to target a specific sound pressure level, asking subjects to speak twice as loud as comfortable, and asking subjects to speak in noise. All three loud conditions resulted in similar increases in sound pressure level . However, the respiratory mechanisms used to support the increase in loudness differed significantly depending on how the louder speech was elicited. When asked to target at a particular sound pressure level, subjects used a mechanism of increasing the lung volume at which speech was initiated to take advantage of higher recoil pressures. When asked to speak twice as loud as comfortable, subjects increased expiratory muscle tension, for the most part, to increase the pressure for speech. However, in the most natural of the elicitation methods, speaking in noise, the subjects used a combined respiratory approach, using both increased recoil pressures and increased expiratory muscle tension. In noise, an additional target, possibly improving intelligibility of speech, was reflected in the slowing of speech rate and in larger volume excursions even though the speakers were producing the same number of syllables. (+info)
Lip kinematics in long and short stop and fricative consonants.
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This paper examines lip and jaw kinematics in the production of labial stop and fricative consonants where the duration of the oral closure/constriction is varied for linguistic purposes. The subjects were speakers of Japanese and Swedish, two languages that have a contrast between short and long consonants. Lip and jaw movements were recorded using a magnetometer system. Based on earlier work showing that the lips are moving at a high velocity at the oral closure, it was hypothesized that speakers could control closure/constriction duration by varying the position of a virtual target for the lips. According to this hypothesis, the peak vertical position of the lower lip during the oral closure/constriction should be higher for the long than for the short consonants. This would result in the lips staying in contact for a longer period. The results show that this is the case for the Japanese subjects and one Swedish subject who produced non-overlapping distributions of closure/ constriction duration for the two categories. However, the peak velocity of the lower lip raising movement did not differ between the two categories. Thus if the lip movements in speech are controlled by specifying a virtual target, that control must involve variations in both the position and the timing of the target. (+info)