ABSTRACT
Introduction. The traditional way of facilitating a good singing voice has been achieved through rigorous voice training. In the modern days, however, there are some aspects of the singing voice that can be enhanced through digital processing. Although in the past, the frequency or intensity manipulations had to be achieved through the various singing techniques of the singer, technology today allows the singing voice to be enhanced from the instruments within recording studios. In es-sence, the traditional voice pedagogy and the evolution of digital audio processing both strive to achieve a better quality of the singing voice, but with different methods. Nevertheless, the major aspects of how the singing voice can be manipulated are not communicated among the professionals in each field.Objective. This paper offers insights as to how the quality of the singing voice can be changed physiologically through the traditional ways of voice training, and also digitally through various instruments that are now available in recording studios.Reflection. The ways in which singers train their voice must be mediated with the audio technology that is available today. Although there are aspects in which the digi-tal technology can aid the singer's voice, there remain areas in which the singers must train their singing system in a physiological level to produce a better singing voice
Introducción. La forma tradicional de facilitar una buena voz para cantar se ha lo-grado mediante un riguroso entrenamiento de la voz. Sin embargo, en la actualidad, existen aspectos de la voz cantada que pueden mejorarse mediante el procesamiento digital. Aunque en el pasado las manipulaciones de frecuencia o intensidad tenían que lograrse a través de las diversas técnicas de canto del cantante, la tecnología actual permite ahora mejorar la voz del canto desde los instrumentos dentro de los estudios de grabación. En esencia, la pedagogía de la voz tradicional y la evolución del procesamiento de audio digital se esfuerzan por lograr una mejor calidad de la voz cantada, pero con métodos diferentes. No obstante, los principales aspectos de cómo se puede manipular la voz cantada no se comunican entre los profesionales de cada campo respectivo. Objetivo. Este artículo ofrece información sobre cómo la calidad de la voz cantada se puede cambiar fisiológicamente a través de las formas tradicionales del entrena-miento de la voz, y también digitalmente a través de varios instrumentos que ahora están disponibles en los estudios de grabación. Reflexión. Las formas en que los cantantes entrenan su voz deben estar mediadas por la tecnología de audio que está disponible en la actualidad. Aunque hay aspectos en los que la tecnología digital puede ayudar a la voz del cantante, quedan áreas en las que los cantantes deben entrenar su sistema de canto a nivel fisiológico para pro-ducir una mejor voz al cantar.
Subject(s)
Voice Quality , Voice Training , Singing , Audiovisual Aids , Voice , Phonetics , Total Quality Management , MusicABSTRACT
BACKGROUND AND OBJECTIVES: Listeners with sensorineural hearing loss want to compensate for their narrow dynamic range from appropriate compression functions of hearing aids. The present study aimed to determine which compression threshold and release time of nonlinear hearing aids might affect speech recognition and speech quality judgments. SUBJECTS AND METHODS: Ten elderly listeners with symmetrical moderate-to-severe sensorineural hearing loss participated in the study. To compare two compression threshold (31 dB SPL vs. 61 dB SPL) and two release time (50 ms vs. 500 ms) conditions, subjects’ speech recognition was measured using the Korean version of the Hearing in Noise Test in both quiet and noisy situations. All subjects were also asked to rate the degree of speech quality in terms of loudness, sharpness, clarity, and background noise immediately after completing the speech recognition test. RESULTS: Although no significant difference emerged in speech recognition thresholds between the two compression thresholds in the quiet situation, the compression threshold of 31 dB SPL showed a lower (or better) signal-to-noise ratio of speech recognition compared to that of 61 dB SPL. The release times of 50 and 500 ms did not statistically differ in both quiet and noisy situations. Subjective categories were found to be louder and clearer in the 50 ms release time for quiet and noisy, respectively. CONCLUSIONS: We expect that these patterns of current results will apply for better-fitting protocol of elderly Korean hearing aid users.
Subject(s)
Aged , Humans , Hearing Aids , Hearing Loss, Sensorineural , Hearing , Judgment , Noise , Signal-To-Noise RatioABSTRACT
BACKGROUND AND OBJECTIVES: Listeners with sensorineural hearing loss want to compensate for their narrow dynamic range from appropriate compression functions of hearing aids. The present study aimed to determine which compression threshold and release time of nonlinear hearing aids might affect speech recognition and speech quality judgments. SUBJECTS AND METHODS: Ten elderly listeners with symmetrical moderate-to-severe sensorineural hearing loss participated in the study. To compare two compression threshold (31 dB SPL vs. 61 dB SPL) and two release time (50 ms vs. 500 ms) conditions, subjects’ speech recognition was measured using the Korean version of the Hearing in Noise Test in both quiet and noisy situations. All subjects were also asked to rate the degree of speech quality in terms of loudness, sharpness, clarity, and background noise immediately after completing the speech recognition test. RESULTS: Although no significant difference emerged in speech recognition thresholds between the two compression thresholds in the quiet situation, the compression threshold of 31 dB SPL showed a lower (or better) signal-to-noise ratio of speech recognition compared to that of 61 dB SPL. The release times of 50 and 500 ms did not statistically differ in both quiet and noisy situations. Subjective categories were found to be louder and clearer in the 50 ms release time for quiet and noisy, respectively. CONCLUSIONS: We expect that these patterns of current results will apply for better-fitting protocol of elderly Korean hearing aid users.
Subject(s)
Aged , Humans , Hearing Aids , Hearing Loss, Sensorineural , Hearing , Judgment , Noise , Signal-To-Noise RatioABSTRACT
BACKGROUND AND OBJECTIVES: The purpose of this study was to identify differences between the dynamic ranges (DRs) of male and female speakers using Korean standard sentence material. Consideration was especially given to effects within the predefined segmentalized frequency-bands. MATERIALS AND METHODS: We used Korean standard sentence lists for adults as stimuli. Each sentence was normalized to a root-mean-square of 65 dB sound pressure level. The sentences were then modified to ensure there were no pauses, and the modified sentences were passed through a filter bank in order to perform the frequency analysis. Finally, the DR was quantified using a histogram that showed the cumulative envelope distribution levels of the speech in each frequency band. RESULTS: In DRs that were averaged across all frequency bands, there were no significant differences between the male and the female speakers. However, when considering effects within the predefined frequency bands, there were significant differences in several frequency bands between the DRs of male speech and those of female speech. CONCLUSIONS: This study shows that the DR of speech for the male speaker differed from the female speaker in nine frequency bands among 21 frequency bands. These observed differences suggest that a standardized DR of male speech in the band-audibility function of the speech intelligibility index may differ from that of female speech derived in the same way. Further studies are required to derive standardized DRs for Korean speakers.
Subject(s)
Adult , Female , Humans , Male , Speech IntelligibilityABSTRACT
Objective To investigate the changes of electrode impedance,threshold(THR),maximum comfortable level(MCL),and dynamic range(DR),providing the basis for debugging after operation in congenital deaf children. Methods A respective study was carried out on 20 cases of congenital deaf children who were implanted with cochlear Med?EL SONATAti100. The measurements and changing ranges of electrode imped?ances,THR,MCL and dynamic range during the operation and at postoperative one month,three months,and six months were statistically analyzed. Results Electrode impedances were the lowest during the operation and the highest at one month after operation(P0.05). Conclusion The electrode impedances varied due to different electrode posi?tion. The vales of THR,MCL and DR were unrelated with electrode impedance. DR was gradually increasing,MCL reached steady state earlier than THR. It is important that THR should be debugged at three months after operation and MCL should be debugged at six months.
ABSTRACT
BACKGROUND AND OBJECTIVES: The goal of mapping after cochlear implantation (CI) is to find a proper range of acoustic signals for the implantees. In young children or infants, however, it is more difficult to obtain reliable responses during mapping procedure. The purpose of this study was to observe the changes of the proper electrical stimulation levels (threshold levels, comfortable levels and dynamic range) in children with the Nucleus 24 cochlear implant system by analyzing postoperative mapping results. SUBJECTS AND METHOD: The maps of 23 children with normal inner ear who received CI were examined at 7 time intervals (1, 6, 12, 24, 36, 48 and 60 months post-connection). RESULTS: The mean value of C levels and DR of 23 children gradually increased according to time from 1 month to 60 months post-connection. The value of T level increased up to 6 months post-connection and then stabilized. CONCLUSION: This study emphasized the need for frequent mapping in the first 6 months of implant use in children. Protocol for regular mapping schedule from 1 year to 5 year post-connection would be necessary.
Subject(s)
Child , Humans , Infant , Acoustics , Appointments and Schedules , Cochlear Implantation , Cochlear Implants , Ear, Inner , Electric StimulationABSTRACT
OBJECTIVE: This study was performed to investigate the effects of low-level laser irradiation on the dorsal horn cell activities in the rats with experimental muscle pain. METHOD: Experimental muscle pain was induced by repeated injections of acidic saline into the gastrocnemius muscle in thirty Sprague-Dawley rats. Activities of ipsilateral dorsal horn cells were recorded with a glass microelectrode at L2-L4 spinal cord level before and after low-level laser irradiation on the injected leg. Cells were categorized as wide dynamic range (WDR) and high threshold (HT) cells by the response to the cotton, vonFrey filament, and forceps stimulation at the receptive area. RESULTS: The spontaneous and mechanically evoked activities of WDR and HT cells were significantly increased in the muscle pain models. Low-level laser irradiation reduced mechanically evoked activities of WDR and HT cells. This effect was maximal at 20 minutes after irradiation and then returned to pre-treatment level in 40~50 minutes. CONCLUSION: The low-level laser irradiation was effective for the management of muscle pain by reducing activities of dorsal horn cells. Low-level laser might be clinically used for the treatment of local and referred pain of muscle origin.
Subject(s)
Animals , Rats , Glass , Leg , Microelectrodes , Muscle, Skeletal , Myalgia , Pain, Referred , Posterior Horn Cells , Rats, Sprague-Dawley , Spinal Cord , Surgical InstrumentsABSTRACT
This paper discusses the research of a digital hearing aid based on DSP TMS320C5416,in which a series of prevalent algorithms in digital hearing aid are realized including dynamic range compression,frequency compression,noise-reduction,directional multi-microphone,etc.This project provides some experience for national development of the hardware and software of the digital hearing aid based on DSP.
ABSTRACT
Systemic arteries show higher vascular disease than pulmonary ones. The aim of this study was to establish regional and functional differences in the mechanical properties of arteries in both circulations. Pressure (Konigsberg) and diameter (Sonomicrometry) were measured in seven artery segments corresponding to each sheep (N=7) using a previously developed mock circulation loop...
Subject(s)
Arteries , Biomechanical Phenomena , Pulmonary ArteryABSTRACT
O controle de qualidade da imagem em equipamentos ultra-sônicos de diagnósticos é baseado em parâmetros determinados por norma (IEC, 1996). Todos os parâmetros citados nesta norma, com exceção da Largura de Banda, podem ser avaliados utilizando-se de phantoms de tecidos biológicos. Baseado em normas e procedimentos internacionais, confeccionou-se um phantom para medição do parâmetro Faixa Dinâmica Exibida. Como material mimetizados de tecido, utilizou-se a solução matriz (agar, glicerina e água) adicionada de pó de grafite, apresentando coeficiente de atenuação (alfa 0) e velocidade da onda ultrasônica (c) compatíveis com a norma (alfa 0 = 0,7 dB.cm elevado a menos 1.MHz elevado a -0,83 e v = 1540 m.s elevado a menos 1). Adicionaram-se como conservantes, os antibióticos: clorafenicol, tetraciclina, penicilina G e os antifúngicos nistativa e anfotericina B. Foi também desenvolvido um protocolo detalhado para aplicação do phantom. Este protocolo foi testado em um aparelho comercial novo e os resultados iniciais apresentaram-se satisfatórios sugerindo sua adequação (tanto do phantom como do protocolo) numa aplicação rotineira em aparelhos comerciais
Subject(s)
Ultrasonography , Phantoms, Imaging , Image Interpretation, Computer-Assisted/instrumentation , Image Interpretation, Computer-Assisted/methods , Radiographic Image Enhancement/instrumentation , Radiographic Image Enhancement/methodsABSTRACT
BACKGROUND AND OBJECTIVES: Hyperacusis is an abnormally strong reaction which occurs within auditory pathways resulting from exposure to moderate sound. More patients are inflicted with it than with tinnitus, accounting for a relatively high proportion of the total tinnitus patients. However, no single test could pass as an objective diagnostic test of hyperacusis. Among various psychoacoustic evaluations, loudness discomfort level (LDL) is frequently used in the evaluation of hyperacusis. Thus, this study aimed to demonstrate a proportion of hyperacusis in tinnitus patients and characterize LDL in hyperacusis and tinnitus patients as a diagnostic test. MATERIALS AND METHOD: Using 186 patients with tinnitus as experiment group and 35 acoustically normal persons as control group, pure tone audiometry (PTA), LDL, and dynamic range (DR) were checked. RESULTS: Amongst the total number of tinnitus patients, there were 10 hyperacusis patients (5.38%). Those hyperacusis patients had much lower LDL (73.50 dB) and DR (41.50 dB) than tinnitus patients without hyperacusis (LDL: 100.90 dB, DR: 67.20 dB) as well as the control group (LDL: 104.86 dB, DR: 93.98 dB). CONCLUSION: Hyperacusis patients consist 5.38% (10/186) and have much lower LDL than tinnitus patients without hyperacusis and the control group. There is a positive correlation between hyperacusis and LDL. Therefore, in a diagnosis of hyperacusis, it is essential to check LDL and take a careful look into the history from patients.
Subject(s)
Humans , Audiometry , Auditory Pathways , Diagnosis , Diagnostic Tests, Routine , Hyperacusis , Psychoacoustics , TinnitusABSTRACT
By using extracellular single unit recording technique, locally suppressive effects of a single dose of ketamine on sub-cutaneous (s. c. ) bee venom-induced increase in firing of wide dynamic-range (WDR) neurons in spinal dorsal horn were investi-gated on urcthane-chloralose anesthetized cats. Injection of bee venom s.c. into the cutaneous receptive field (RF) resulted in asingle phase of prolonged, persistently increased firing of WDR neurons over background activity for more than 1 h. Local pre-treatment with ketamine (100 mM, 0. 1 m l) into the center of RF where bee venom was injected produced a dramatic suppressionof the increased neuronal firing by 60% (3.10± 0.42 spikes/s, n= 5) when compared with saline pre-treated group (7.61 ± 0.17spikes/ s. n = 5 ). Moreover, local post-treatment with the same dose of ketamine also produced a profound suppression of the in-creased neuronal activity by 81% (1.51±0.06 spikes/s, n=5) when compared with the saline post-treated group (7.76±0.15spikes s, n=5). However, s.c. administration with the same dose of ketamine into a symmetrical region on the bee venom un-treated contralateral hindpaw produced no affection on the increased firing of the WDR neurons, suggesting that the suppressiveaction of local ketamine was not the result of systemic effects. The present result suggests that ketamine may exert its localantinociceptive effects mainly through the peripheral NMDA receptors in addition to its partially potential blocking effects onsodium and voltage-sensitive calcium channels.
ABSTRACT
Somatostatin (SOM) is one of the major neuropeptides in dorsal root ganglion cells, but its role in spinal nociceptive process has not been well known. In present study we aimed to investigate the effect of SOM on the response of dorsal horn neurons to the various types of peripheral nociceptive stimuli in anesthetized cats. Using carbon-filament microelectrode, the single cell activities of wide dynamic range neurons were recorded from the lumbosacral enlargement after noxious mechanical (squeeze), thermal (radiant heat lamp) and cold (dry ice) stimulation to the receptive field. Sciatic nerve was stimulated electrically to evoke A delta- and C-nociceptive responses SOM analogue, octreotide (10 mug/kg), was applied intravenously and the results were compared with those of morphine (2 mg/kg, MOR) Systemic SOM decreased the cellular responses to the noxious heat and the mechanical stimulation, but increased those to the cold stimulation. In the responses to the electric stimuli of sciatic nerve, A delta-nociceptive response was increased by SOM, while C-nociceptive response was decreased. On the other hand, MOR inhibited the dorsal horn cell responses to all the noxious stimuli. From the above results, it is concluded that SOM suppresses the transmission of nociceptive heat and mechanical stimuli, especially via C-fiber, while it facilitates those of nociceptive cold stimuli via A delta-fiber.
Subject(s)
Animals , Cats , Ganglia, Spinal , Hand , Hot Temperature , Microelectrodes , Morphine , Neurons , Neuropeptides , Octreotide , Posterior Horn Cells , Sciatic Nerve , Somatostatin , Spinal CordABSTRACT
The aim of the present study is to examine the brainstem sites where the electrical stimulation produces a suppression of dorsal horn neuron responses of neuropathic rats. An experimental neuropathy was induced by a unilateral ligation of L5-L6 spinal nerves of rats. Ten to 15 days after surgery, the spinal cord was exposed and single-unit recording was made on wide dynamic range (WDR) neurons in the dorsal horn. Neuronal responses to mechanical stimuli applied to somatic receptive fields were examined to see if they were modulated by electrical stimulation of various brainstem sites. Electrical stimulation of periaqueductal gray (PAG), n. raphe magnus (RMg) or n. reticularis gigantocellularis (Gi) significantly suppressed responses of WDR neurons to both noxious and non-noxious stimuli. Electrical stimulation of other brainstem areas, such as locus coeruleus. (LC) and n. reticularis paragigantocellularis lateralis (LPGi), produced little or no suppression. Microinjection of morphine into PAG, RMg, or Gi also produced a suppression as similar pattern to the case of electrical stimulation, whereas morphine injection into LC or LPGi exerted no effects. The results suggest that PAG, NRM and Gi are the principle brainstem nuclei involved in the descending inhibitory systems responsible for the control of neuropathic pain. These systems are likely activated by endogenous opioids and exert their inhibitory effect by acting on WDR neurons in the spinal cord.