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101.
We evaluated the neural substrates of cross-modal binding and divided attention during audio-visual speech integration using functional magnetic resonance imaging. The subjects (n = 17) were exposed to phonemically concordant or discordant auditory and visual speech stimuli. Three different matching tasks were performed: auditory-auditory (AA), visual-visual (VV) and auditory-visual (AV). Subjects were asked whether the prompted pair were congruent or not. We defined the neural substrates for the within-modal matching tasks by VV-AA and AA-VV. We defined the cross-modal area as the intersection of the loci defined by AV-AA and AV-VV. The auditory task activated the bilateral anterior superior temporal gyrus and superior temporal sulcus, the left planum temporale and left lingual gyrus. The visual task activated the bilateral middle and inferior frontal gyrus, right occipito-temporal junction, intraparietal sulcus and left cerebellum. The bilateral dorsal premotor cortex, posterior parietal cortex (including the bilateral superior parietal lobule and the left intraparietal sulcus) and right cerebellum showed more prominent activation during AV compared with AA and VV. Within these areas, the posterior parietal cortex showed more activation during concordant than discordant stimuli, and hence was related to cross-modal binding. Our results indicate a close relationship between cross-modal attentional control and cross-modal binding during speech reading.  相似文献   
102.
The aim of the study was to analyze and quantify the voice characteristics of reflux laryngitis (RL) patients and to determine the most important voice tests and voice-quality parameters in the functional diagnostics of RL. The voices of 83 RL patients and 31 persons in the control group were evaluated. Vocal function was assessed using a multidimensional set of video laryngostroboscopic, perceptual, acoustic, aerodynamic and subjective measurements according to the protocol elaborated by the Committee on Phoniatrics of the European Laryngological Society. The mean values of the hoarseness visual analogue scale assessment and voice handicap index were significantly higher (P<0.05) in the group of RL patients as compared to the controls. Objective voice assessment revealed a significant increase in mean values of jitter, shimmer and normalized noise energy (NNE), along with a significant decrease in pitch range, maximum frequency, phonetogram area (S) and maximum phonation time (MPT) in RL patients, both in the male and female subgroups. According to the results of discriminant analysis, the NNE, MPT, S and intensity range were determined as an optimum set for functional diagnostics of RL. The derived function (equation) makes it possible to assign the person to the group of RL patients with an accuracy of 86.7%. The sensitivity and specificity of eight voice parameters were found to be higher than 50%. The results of the present study demonstrate a reduction of phonation capabilities and voice quality in RL patients. Multidimensional voice evaluation makes it possible to detect significant differences in mean values of perceptual, subjective and objective voice quality parameters between RL patients and controls groups. Therefore, multidimensional voice analysis is an important tool in the functional diagnostics of RL.This study was presented at the 4th Congress of the European Laryngological Society, Brussels, 5–7 September 2002.  相似文献   
103.
Behrman A  Sulica L  He T 《The Laryngoscope》2004,114(10):1693-1700
OBJECTIVES/HYPOTHESIS: To assess factors that may be predictive of patient perception of dysphonia severity, as quantified by the Voice Handicap Index (VHI) score. We hypothesize that 1) level of vocal demand; 2) auditory-perceptual evaluation of dysphonia severity; and 3) vocal function, as defined by phonatory glottal closure and mucosal wave vibration, are the most significant predictors of VHI score. STUDY DESIGN:: Retrospective review of 100 patients with benign vocal fold lesions. METHODS: Variables assessed for predictive value to VHI score are level of vocal demands, auditory-perceptual evaluation of dysphonia severity, integrity of mucosal wave vibration and phonatory glottal closure, lesion type, duration of current complaint, smoking, age, and sex. Harmonic to noise ratio was assessed in a subset of 50 patients. RESULTS: Patients with routine voice use had significantly lower VHI scores than those with more intensive (nonsinging/acting) vocal demands. Patients who quit smoking had greater VHI scores than those who currently smoke or never started. Patients with long-standing dysphonia tended to have lower VHI scores than those with shorter duration vocal complaints. Auditory-perceptual assessment of dysphonia severity and harmonic to noise ratio were weak predictors of VHI score. Age, sex, lesion type, phonatory glottal closure, and mucosal wave vibration were not significant predictors of VHI score. CONCLUSIONS: Patient perception of dysphonia severity is independent of many factors commonly assessed during the evaluation of voice disorders. It appears to be an important independent element in the assessment of the effect of a benign vocal fold lesion and critical to therapeutic decision-making.  相似文献   
104.
OBJECTIVES/HYPOTHESIS: The main purpose of the study was to determine the impact of uvulopalatopharyngoplasty (UPPP) on nasalance and nasality. It was hypothesized that nasalance would change from the presurgical to the postsurgical condition because the surgical protocol involves removal of palatal tissue. An additional objective of the study was to provide objective and subjective data about changes in voice and articulation after UPPP. Because the surgical procedure of UPPP does not involve laryngeal tissue, it was hypothesized that the voice characteristics remain relatively stable. Because of removal of effective velar length, articulation problems of the uvular /R/ can occur in the Dutch language. STUDY DESIGN: Prospective study in which 26 men were studied before (1 week before UPPP) and after (3 weeks after UPPP) surgery. METHODS: The Nasometer was used to obtain nasalance scores. The mirror-fogging test, a perceptual evaluation of each subject's readings, and the Gutzmann and the Bzoch hypernasality tests were used for the assessment of nasality. For the assessment of articulation, a phonetic analysis was performed. Voice assessment included a perceptual rating of the voice and a determination of fundamental frequency. RESULTS: No significant differences were found between the conditions before and after surgery regarding nasalance (except for the vowel /i/), nasality, and voice. Regarding articulation, only 1 patient showed a derhotacized /R/. CONCLUSIONS: The findings of the study indicate that UPPP does not have an impact on nasality, voice, and articulation. Regarding nasalance, no significant nasalance change occurred after UPPP, except for the high vowel /i/.  相似文献   
105.
目的开发一个方便实用的医疗收费提示系统。方法以单片机为核心构造系统接口、语音提示、显示提示等模块,实现对医疗收费信息的双重提示。结果系统在单片机8032的控制下可以通过语音芯片实现语音提示,通过LED实现显示提示。结论“医疗收费提示系统”具有语音提示和显示提示双重提示功能,方便实用,为提高收费结算效率提供了有力的支持。  相似文献   
106.
OBJECTIVE: To improve the voice quality of female laryngectomees and/or laryngectomees with a hypotonic pharyngoesophageal (PE) segment by means of a pneumatic artificial source of voice incorporated in a regular tracheoesophageal (TE) shunt valve. STUDY DESIGN: Experimental, randomized, crossover trial. METHODS: The new sound source consists of a single silicone lip, which performs an oscillatory movement driven by expired pulmonary air flowing along the outward-striking lip through the TE shunt valve. A prototype of this pneumatic sound source is evaluated in vitro and in six laryngectomees. In vivo evaluation includes speech rate, maximal phonation time, perceptual voice evaluation of read-aloud prose by an expert listener, speech intelligibility measurements with 12 listeners, and self-assessment by the patients. Moreover, extensive acoustical and aerodynamic in vivo registrations are performed using a newly developed data acquisition system. RESULTS: The current prototype seems beneficial in female laryngectomees with a hypotonic PE segment only. For them the sound-producing voice prosthesis improves voice quality and increases the average pitch of voice, without decreasing intelligibility or necessitating other pressure and airflow rates than regular TE shunt speech. Pitch regulation of this prosthetic voice is possible, yet limited. CONCLUSIONS: The mechanism is feasible and does not result in unacceptable airflow resistance. For this new mechanism of alaryngeal voice to become an established technique for postlaryngectomy voice restoration, a voice suitably pitched for male laryngectomees has to be generated and a large part of the melodic and dynamic range of the sound source has to be attainable within physiological airflow rates.  相似文献   
107.
INTRODUCTION: Glottal insufficiency resulting from vocal fold bowing, hypomobility, or scar is frequently treated by injection augmentation. Injection augmentation with fat, collagen, gel foam, polytef, and recently, fascia lata has been previously reported. Variable graft yield and poor host-tissue tolerance have motivated the continued search for an ideal graft substance. STUDY DESIGN: A prospective trial of autologous fascia augmentation of the vocal cord in the human and in an animal model. METHODS: Autologous fascia injection augmentation (AFIA) was evaluated in 8 canines and 40 patients at our institution between 1998 and 2000. The animal study compared graft yield from AFIA with autologous fat yield. The outcome measure was graft yield calculated from histological examination of larynges 12 weeks after injection augmentation. Clinical trial outcome measures included symptom surveys, acoustical voice analyses, and subjective voice assessments. Mean follow-up was 9 months. RESULTS: In the canine larynx, the mean graft yield for AFIA was 33% (range, 5%-84%) compared with autologous lipoinjection (47%; range, 7%-96%; P =.57). Subjective improvement in vocal quality was reported by 95% of patients (38 of 40) after AFIA. Preoperative and postoperative voice analysis data were obtained from 26 patients. Subjective voice rating demonstrated a significant improvement after AFIA (P <.0001). Acoustical parameters of jitter, shimmer, noise-to-harmonic ratio, phonatory range, and degree unvoiced improved significantly (P <.05) in all patients after fascia augmentation. CONCLUSIONS: Based on the animal study, we concluded that graft yields are excellent but variable for AFIA. The result is similar in variability and overall yield to autologous lipoinjection. Subjective and objective analyses of voice outcomes after AFIA are universally improved. Fascia appears to be an excellent alternative to lipoinjection in properly selected cases of glottic insufficiency.  相似文献   
108.
Improving the functional outcome of Tucker's reconstructive laryngectomy   总被引:2,自引:0,他引:2  
Lawson G  Jamart J  Remacle M 《Head & neck》2001,23(10):871-878
BACKGROUND: The goal of reconstructive laryngectomy addressing glottic carcinoma, as described by Tucker, is twofold: achieve local control and preserve as much as possible the physiological laryngeal function. METHODS: The study consisted of long-term assessment of oncological, deglutitory, and vocal outcome in 34 patients following Tucker's reconstructive laryngectomy. Postoperative follow-up included fiberscopic examination, videoradiography, and voice assessment after speech rehabilitation. RESULTS: The 5-year overall survival rate was 92% +/- 5%. Fiberscopic examination and videoradiography contributed to observing and understanding the rehabilitation process and impairment to its progress. Two main compensatory movements were identified: the anticipatory backward movement of the tongue base (50%) and the anticipatory upward laryngeal motion (15%). Both movements occurred simultaneously at the beginning of the pharyngeal stage of the swallow (35%). The median duration prior to tracheostomy tube removal was 14 days. Swallowing of solids resumed on day 9 (median), and liquid intake (water and soup) resumed on day 12 (median). The median duration of hospitalization was 16 days. Following speech rehabilitation, the latest follow-up visit measured as follows: the mean conversational voice intensity at 64 dB (range, 57-79 dB); the mean maximum intensity at 87 dB (range, 78-96 dB); the minimum intensity at 54 dB (range, 45-65 dB); the mean maximum phonation time at 16 seconds (range, 10-29 seconds); and the mean phonation quotient at 284 mL/second (range, 205-341 mL/second). According to our classification, voice spectral analysis revealed 19 class-III patients, 12 class-II patients, and three class-I patients. CONCLUSION: Tucker's reconstructive laryngectomy is reliable in terms of both the oncological and functional outcome. Fiberscopic examination and videoradiography are two complementary methods for assessing postoperative deglutition.  相似文献   
109.
Objective. To develop an ergonomically designed computerized recordkeeping tool for anesthesiologists that allows the clinician to maintain visual contact with the patient while performing recordkeeping. Methods.To simplify the human interface software, we developed two general use software components. All purpose menu type 1 (APM1) was used for entering events using a tree structured menu. APM1 was designed to adapt to the limits of human memory, by using Miller's rule of 7 to guide the input process. APM1 can be considered to be a three-dimensional table list consisting of 7 vertical and 7 horizontal choices, which has further 5 tree-structured divergences. APM1 is also completely configurable by the user. All purpose menu 2 (APM2) was used to implement the system-initiated human interface where the system will prompt the user by voice for each entry. When users touch a key on APM1 and APM2, the system was designed to respond with a voice prompt. A touch-screen was also utilized and designed to fit the anesthesia machine. The screen is equipped with a small speaker for voice response and a microphone for voice recognition. The positions of the screen are adjustable supported by a long flexible limb (85 cm). Results. After improving the design, systems were assembled for 10 operating rooms. Of the multiple features of the VOCAAR user interface, the following were well accepted by users and employed daily: touch-screen input, and voice response. The noncompulsory use rate was 87% during the initial 2 weeks, increased to 94% after 2 weeks and 100% after two months. The mean sound emission by voice response (n = 10, mean ± SD) was 8.2 ± 2.3 dB at the main anesthetist site (35 cm from the speaker mounted on the touch-screen), 2.2 ± 1.3 dB at the staff site (1.5 m from the touch-screen), which was only audible for anesthesiologist but for surgeon. Discussion. An EARK system was designed to allow the user to maintain visual contact with the patient while performing recordkeeping tasks. The combination of a mobile touch screen and voice response/recognition facilitated the design goals of the system. Although the system has enjoyed universal clinical acceptance, the voice functions remain too limited to satisfy the needs of a completely handsfree user interface. Enhancements to voice recognition technology will offer the potential for improved functionality. Additional research is also needed to better define the relationship between vigilance and visual contact with the patient.  相似文献   
110.
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