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151.
Although resonant voice therapy is a widely used therapeutic approach, little is known about what characterizes resonant voice and how it is physiologically produced. The purpose of this study was to test the hypothesis that resonant voice is produced by narrowing the laryngeal vestibule and is characterized by first formant tuning and more ample harmonics. Videonasendoscopic recordings of the laryngeal vestibule were made during nonresonant and resonant productions of /i/ in six subjects. Spectrums of the two voice types were also obtained. Spectral analysis showed that first formant tuning was exhibited during resonant voice productions and that the degree of harmonic enhancement in the range of 2.0 to 3.5 kHz was related to voice quality: nonresonant voice had the least amount of energy in this range, whereas a resonant-relaxed voice had more energy, and a resonant-bright voice had the greatest amount of energy. Visual-perceptual judgments of the videoendoscopic data indicated that laryngeal vestibule constriction was not consistently associated with resonant voice production.  相似文献   
152.
A voice range profile (VRP) was obtained from each of eight professional actors and compared with two speech range profiles (SRPs). One speech profile was obtained during the dramatic reading of a scene in the laboratory and the other during a performance on stage in a professional theater. The objective was to determine the pitch and loudness ranges used by the actors in speech relative to the VRP. The principal question of interest was whether the actors stayed within the center of the VRP, or whether they tended to drift toward the boundaries of intensity and frequency. A second question was whether the performance within the laboratory accurately reflects that of a stage performance. The results suggest that some subjects tend to exceed the center of the VRP during the stage performance. It is hypothesized that these actors may stress their vocal mechanism during performance and are more likely candidates for vocal injury.  相似文献   
153.
每根钢管都有一个声音节点,在此节点上固定钢管敲击时,就会发出特别清脆悦耳的声音.实验发现节点位置处于钢管长度的三分之一处,声音频率反比与钢管长度.空气柱与钢管的共振可以说明这个现象.  相似文献   
154.
根据抗荷服系统性能测试对气源和过载的要求,设计和实现了基于电气比例阀、音圈电机和LabVIEW的地面测试平台。平台采用直线机器人完成被测件的精确定位,应用压力控制负反馈技术,实现了0.01~3MPa的气源压力控制,提出了使用电磁力动态模拟过载的新方法,可在地面获取抗荷服系统的压力和流量动态响应曲线。试验结果表明,平台的定位精度小于5μm,动态过载模拟精度小于0.1G/s,气源压力控制稳定,人机界面友好,能够满足抗荷服系统地面测试需求。  相似文献   
155.
156.
It is generally accepted that psychogenic voice disorder (PVD) is aresult of psychosocial stress; however, systematic studies of etiological factors in this condition are few. Furthermore, although immediate effects of therapy are estimated to be good, relapses are frequent, and the long-term effects of therapy are not known. The present prospective and longitudinal study on 30 patients was thus focused on possible etiological factors, the course of therapy, and the long-term results of therapy for PVD. The results indicate that interpersonal conflicts related to family and work are of basic importance in precipitating this condition. PVD is interpreted as a specific disorder of verbal emotional expression. Our therapy model in which vocal exercises are performed, together with training of communicative skills, seems rewarding. Relapses were not reported in 88% of the patients during the followup period of 1.9-8.4 years after therapy.  相似文献   
157.
This study investigated changes in maximum phonation time andacoustic and perceptual measures of voice following topical anesthesia and laryngeal endoscopy with the flexible endoscope. Forty-four females, aged 18–33 years and with normal voices, performed four vocal tasks: (a) 3-second /i/ prolongation, (b) maximum phonation time on /i/, (c) stepwise scale-singing, and (d) reading a standard passage. Subjects performed these tasks prior to anesthesia, after anesthesia, and again during laryngeal endoscopy. Voice samples were analyzed for jitter, shimmer, harmonic-to-noise ratio, speaking fundamental frequency, maximum phonational frequency range, maximum phonation time, harshness, and breathiness. Results demonstrated significant reductions in maximum phonational frequency range following anesthesia and, during laryngeal endoscopy, reductions in maximum phonation time and increases in speaking fundamental frequency, minimum fundamental frequency on scale-singing, and breathiness. Clinicians using laryngeal endoscopy for evaluation and management of vocal dysfunction should, therefore, consider the possible effects of these procedures on vocal functioning.  相似文献   
158.
This investigation studied the effect of a systematized vocal warm-up procedure on voices with disorders. There were 4 subjects with voice disorders. To optimize vocal function a systematized vocal warm-up system was developed by the author for singers and nonsingers alike. Subjects were asked to practice the vocal warm-up exercises daily, with weekly monitoring in the studio. Data from independent raters and subjects' self-ratings were compared to and corroborated with computer analysis of audio samples. Results indicated significant improvement in subjects' voices that were increasingly maintained over time.  相似文献   
159.
Sex hormones and the female voice   总被引:3,自引:0,他引:3  
In the following, the authors examine the relationship between hormonal climate and the female voice through discussion of hormonal biochemistry and physiology and informal reporting on a study of 197 women with either premenstrual or menopausal voice syndrome. These facts are placed in a larger historical and cultural context, which is inextricably bound to the understanding of the female voice. The female voice evolves from childhood to menopause, under the varied influences of estrogens, progesterone, and testosterone. These hormones are the dominant factor in determining voice changes throughout life. For example, a woman's voice always develops masculine characteristics after an injection of testosterone. Such a change is irreversible. Conversely, male castrati had feminine voices because they lacked the physiologic changes associated with testosterone. The vocal instrument is comprised of the vibratory body, the respiratory power source and the oropharyngeal resonating chambers. Voice is characterized by its intensity, frequency, and harmonics. The harmonics are hormonally dependent. This is illustrated by the changes that occur during male and female puberty: In the female, the impact of estrogens at puberty, in concert with progesterone, produces the characteristics of the female voice, with a fundamental frequency one third lower than that of a child. In the male, androgens released at puberty are responsible for the male vocal frequency, an octave lower than that of a child. Premenstrual vocal syndrome is characterized by vocal fatigue, decreased range, a loss of power and loss of certain harmonics. The syndrome usually starts some 4-5 days before menstruation in some 33% of women. Vocal professionals are particularly affected. Dynamic vocal exploration by televideoendoscopy shows congestion, microvarices, edema of the posterior third of the vocal folds and a loss of its vibratory amplitude. The authors studied 97 premenstrual women who were prescribed a treatment of multivitamins, venous tone stimulants (phlebotonics), and anti-edematous drugs. We obtained symptomatic improvement in 84 patients. The menopausal vocal syndrome is characterized by lowered vocal intensity, vocal fatigue, a decreased range with loss of the high tones and a loss of vocal quality. In a study of 100 menopausal women, 17 presented with a menopausal vocal syndrome. To rehabilitate their voices, and thus their professional lives, patients were prescribed hormone replacement therapy and multi-vitamins. All 97 women showed signs of vocal muscle atrophy, reduction in the thickness of the mucosa and reduced mobility in the cricoarytenoid joint. Multi-factorial therapy (hormone replacement therapy and multi-vitamins) has to be individually adjusted to each case depending on body type, vocal needs, and other factors.  相似文献   
160.
Vocal fold scar disrupts the mucosal wave and interferes with glottic closure. Treatment involves a multidisciplinary approach that includes voice therapy, medical management, and sometimes surgery. We reviewed the records of the first eight patients who underwent autologous fat implantation for vocal fold scar. Information on the etiology of scar, physical findings, and prior interventions were collected. Videotapes of videostroboscopic findings and perceptual voice ratings [Grade, Roughness, Breathiness, Asthenia, Strain (GRBAS)] were randomized and analyzed independently by four blinded observers. Etiology of scar included mass excision (7), vocal fold stripping (3), congenital sulcus (2), and hemorrhage (1). Prior surgical procedures performed included thyroplasty (1), autologous fat injection (9), excision of scar (2), and lysis of adhesions (2). Strobovideolaryngoscopy: Statistically significant improvement was found in glottic closure, mucosal wave, and stiffness (P = 0.05). Perceptual ratings (GRBAS): Statistically significant improvement was found in all five parameters, including overall Grade, Roughness, Breathiness, Asthenia, and Strain (P = 0.05). Patients appear to have improved vocal fold function and quality of voice after autologous fat implantation in the vocal fold. Autologous fat implantation is an important adjunctive procedure in the management of vocal fold scar, and a useful addition to the armamentarium of the experienced phonomicrosurgeon.  相似文献   
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