A Novel Implantable Hearing System with Direct Acoustic Cochlear Stimulation

A new implantable hearing system, the direct acoustic cochlear stimulator (DACS) is presented. This system is based on the principle of a power-driven stapes prosthesis and intended for the treatment of severe mixed hearing loss due to advanced otosclerosis. It consists of an implantable electromagnetic transducer, which transfers acoustic energy directly to the inner ear, and an audio processor worn externally behind the implanted ear. The device is implanted using a specially developed retromeatal microsurgical approach. After removal of the stapes, a conventional stapes prosthesis is attached to the transducer and placed in the oval window to allow direct acoustical coupling to the perilymph of the inner ear. In order to restore the natural sound transmission of the ossicular chain, a second stapes prosthesis is placed in parallel to the first one into the oval window and attached to the patient's own incus, as in a conventional stapedectomy. Four patients were implanted with an investigational DACS device. The hearing threshold of the implanted ears before implantation ranged from 78 to 101 dB (air conduction, pure tone average, 0.5-4 kHz) with air-bone gaps of 33-44 dB in the same frequency range. Postoperatively, substantial improvements in sound field thresholds, speech intelligibility as well as in the subjective assessment of everyday situations were found in all patients. Two years after the implantations, monosyllabic word recognition scores in quiet at 75 dB improved by 45-100 percent points when using the DACS. Furthermore, hearing thresholds were already improved by the second stapes prosthesis alone by 14-28 dB (pure tone average 0.5-4 kHz, DACS switched off). No device-related serious medical complications occurred and all patients have continued to use their device on a daily basis for over 2 years. Copyright (c) 2008 S. Karger AG, Basel.

Functional outcome after total and subtotal glossectomy with free flap reconstruction

BACKGROUND: The aim of this study was to evaluate postoperative oral functions of patients who had undergone total or subtotal (75%) glossectomy with preservation of the larynx for oral squamous cell carcinomas. METHODS: Speech intelligibility and swallowing capacity of 17 patients who had been treated between 1992 and 2002 were scored and classified using standard protocols 6 to 36 months postoperatively. The outcomes were finally rated as good, acceptable, or poor. RESULTS: The 4-year disease-specific survival rate was 64%. Speech intelligibility and swallowing capacity were satisfactory (acceptable or good) in 82.3%. Only 3 patients were still dependent on tube feeding. Good speech perceptibility did not always go together with normal diet tolerance, however. CONCLUSIONS: Our satisfactory results are attributable to the use of large, voluminous soft tissue flaps for reconstruction, and to the instigation of postoperative swallowing and speech therapy on a routine basis and at an early juncture. (c) 2008 Wiley Periodicals, Inc. Head Neck, 2008.

Empleo de materiales reciclados para centros educativos en Chile

Los objetivos de este proyecto son dobles. El primero a conseguir es el acondicionamiento acústico de un centro educativo para alcanzar un mayor rendimiento docente; lo que se pretende lograr mejorando la inteligibilidad de la palabra y reduciendo el ruido en los diferentes recintos. El segundo objetivo, es la reducción de los costos económicos y medioambientales del proyecto empleando en el acondicionamiento acústico materiales procedentes del reciclado o existentes en el entorno local, reduciendo lo mayor posible la importación de estos materiales. Desde la investigación de las exigencias acústicas de un centro educativo, se determinarán los parámetros adecuados para su diseño óptimo. En general los mayores problemas acústicos existentes en estos establecimientos, son debidos a la transferencia de ruido entre los diferentes recintos y su excesiva reverberación, lo que provoca dificultades en la transmisión de la palabra y por ende también en las actividades docentes y los objetivos educativos. Asimismo, los parámetros y exigencias acústicas planteadas y desarrolladas, serán estudiados a partir de un contexto real y específico. El lugar elegido para el caso de estudio, será la ciudad de Santiago de Chile. Es importante, aclarar que en este país no existe una normativa aplicable a este tipo de establecimientos, por tanto se planteará el aislamiento acústico y posterior acondicionamiento a partir de normas y requisitos internacionales. Además, las soluciones acústicas planteadas serán de materiales reciclados existentes en el mercado nacional. Esta decisión tiene como finalidad reducir la afección al medio ambiente fomentando el desarrollo ecológico y sostenible como respuesta al crecimiento económico y la conservación de recursos en un país que se encuentra en vías de desarrollo. Por último, se plantea el acondicionamiento acústico de los diferentes recintos del colegio en proyecto, mediante simulación acústica en el programa EASE (Enhanced Acoustic Simulator for Engineers), lo que nos permite conocer el comportamiento de los recintos antes y después del acondicionamiento acústico. SUMMARY The objective of this Project is twofold. On the one hand, the acoustic conditioning of a school is developed in order to achieve a better teaching performance. For this purpose, the speech intelligibility is enhanced and the noise in the different rooms is reduced. On the other hand, the economic costs and environmental impact are reduced by using recycled materials or materials found in the local area, reducing as much as possible the use of imported materials. The appropriate acoustic parameters will be determined from the evaluation of the acoustic demands of the school. The main problems in these environments are the noise transmission between rooms as well as a high reverberation time. These will cause problems with the speech transmission, which is of great importance for educational purposes. Furthermore, the acoustic parameters and requirements are taken from a real and specific context. The place chosen for the research is Santiago, Chile. It is remarkable that in this country there is no national legislation that can be applied to such places, therefore International Standards are considered to evaluate the acoustic insulation and conditioning. The acoustic solutions considered in this project come from recycled materials existing on the domestic market. The decision aims to reduce the environmental impact, promoting environmentally sustainable development as a response to the economic growth and the maintenance of resources in a developing country. Finally, a simulation at some different areas of the school is carried out, comparing the behaviour before and after the proposed acoustic solutions. The software used for the simulations is EASE (Enhanced Acoustic Simulator for Engineers).

Análisis de la distribución espacial de los parámetros acústicos en recintos

El principal objetivo de este estudio es la evaluación de la distribución espacial de los parámetros acústicos en un recinto a través de la aplicación de técnicas geoestadísticas como el método Kriging. Mediante el uso de la herramienta de análisis espacial ArcMap, perteneciente a la plataforma ArcGIS, se ha analizado el comportamiento acústico del Salón de Actos común a la Escuela Técnica Superior de Ingeniería y Sistemas de Telecomunicación (ETSIST) y la Escuela Técnica Superior de Ingeniería de Sistemas Informáticos (ETSISI), ambas situadas en el Campus Sur de la Universidad Politécnica de Madrid. Se han realizado mediciones in-situ del recinto no ocupado utilizando la herramienta de medición DIRAC Room Acoustics y el método de la respuesta impulsiva integrada, extrayéndose los parámetros acústicos de tiempo de reverberación (RT), tiempo de reverberación inicial (EDT), fuerza sonora relativa (Grel), claridad (C80), tiempo central (Ts), definición (D50) e Índice de Transmisión Rápida de la Palabra (RASTI). Se ha analizado la adecuación de los valores observados de Grel, C80 y Ts al modelo teórico de Barron y estimado, mediante el método Kriging Ordinario, el conjunto de parámetros medidos en el recinto, obteniéndose los semivariograma y mapas de estimación correspondientes. Además, se ha evaluado la calidad de la estimación en base a un número de puntos de medición reducido. A la vista de los resultados obtenidos, en general, el método Kriging puede considerarse un buen interpolador de los parámetros acústicos en un recinto, observándose que los parámetros que evalúan relaciones energéticas, especialmente la fuerza sonora relativa (Grel) proporcionan mejores estimaciones en comparación con aquellos relacionados con la reverberación y la inteligibilidad del habla. El coeficiente de determinación (R2) constituye una medida útil para evaluar la precisión de la estimación. Además, la entropía de los datos observados puede ser un buen indicador a priori de la precisión de la estimación. Asimismo, se ha demostrado que, basándose en un reducido número de puntos de medición, es posible obtener una estimación precisa de los parámetros acústicos de fuerza sonora relativa (Grel) y tiempo central (Ts). ABSTRACT. This project aims to evaluate the feasibility of using geostatistical techniques such as Kriging on the analysis of the spatial distribution of the acoustic parameters in rooms. The acoustic behaviour of the Assembly Hall of the ETSIST and ETSISI (Universidad Politécnica de Madrid) is investigated using ArcMap, which is the main component of ArcGIS suite of geospatial processing programs. For this purpose, in-situ acoustic measurements are carried out in the unoccupied room using DIRAC Room Acoustics software. The following acoustic parameters are measured by means of the integrated impulse response method for further examination: Reverberation Time (RT), Early Decay Time (EDT), Relative Strength (Grel), Clarity (C80), Centre Time (Ts), Definition (D50) and Rapid Speech Transmission Index (RASTI). Goodness-of-fit of measured Grel, C80 and Ts values to Barron’s theory is determined and Ordinary Kriging is applied to all the measured parameters in order to calculate the semivariogram and prediction surfaces. The prediction performance is also analysed when significantly fewer receiver positions are used for the prediction. The experimental results obtained lead to conclude that Kriging can be successfully applied to room acoustics. Energy\based acoustic parameters can be estimated with higher accuracy compared to those related to reverberation and speech intelligibility. Coefficient of determination (R2) is a reliable statistic for assessing the prediction accuracy, for which measured data entropy can also be a good a priori indicator. Furthermore, based on fewer receiver positions, it is demonstrated that accurate predictions of Grel and Ts can be achieved.

Acoustic study of the Compañía de Jesús church. Characterization by means of objective and subjective parameters

This work shows the objective results of the acoustic quality of the Compañia de Jesús Church in Cordoba, Argentina. The acoustics of this Temple, built by the Orden Jesuita (Jesuit Order) two centuries ago and declared a World Heritage Site by UNESCO in 2000, is currently considered optimal by musicians as well as general public. In the second half of XVI century, with the Catholic reform, the need for improved speech intelligibility was given priority, being the Jesuit one of the orders that gave most importance to the construction of their temples. This church has constructive and spatial characteristics consistent with those needs. With the purpose of carrying out the acoustic assessment of the precincts, a work methodology that allowed comparing the results obtained from objective measures was developed by means of implementation of field measurements and space modeling, with subjective appreciation results, by developing surveys, with the aim of characterizing acoustically the sound space. This paper shows the comparison between the subjective results and objective criteria, which allowed important conclusions on the acoustic behavior of the temple to be obtained. In this way interesting data were obtained in relation to the subjective response of the acoustics of the church.

Estudio acústico del auditorio Rafael Frühbeck, Burgos

El presente proyecto desarrolla un estudio acústico del recinto: Auditorio Rafael Frühbeck de Burgos, cumpliendo con las indicaciones exigidas por la norma UNE-EN ISO 3382-1: 2010, “Medición de parámetros acústicos en recintos, Parte 1: Salas de Espectáculos”. Se desarrollan dos estudios acústicos sobre el mismo recinto. En el primero de ellos, el recinto está configurado para la realización de eventos tales como conferencias o congresos, donde la inteligibilidad de la palabra es un factor determinante. En el segundo estudio, el recinto se configura para espectáculos musicales como conciertos de orquesta sinfónica o música de cámara. En esta configuración, la palabra ya no es tan determinante como la correcta interpretación y disfrute de la música por parte de la audiencia. Para ambas configuraciones del recinto se ha realizado un procesado estadístico de los datos con el fin de obtener un valor único de cada parámetro acústico estudiado. De esta forma, se comparan los resultados para ambas configuraciones, y se evalúan los valores obtenidos de cada uno de los parámetros acústicos con el fin de conocer si se adecuan a las necesidades acústicas exigidas por el tipo de evento desarrollado. Además, se ha construido un modelo geométrico del recinto por ordenador, para ambas configuraciones acústicas, haciendo uso del software profesional de predicción y simulación acústica EASE. Se realiza un estudio acústico sobre el modelo geométrico mediante simulación, siguiendo las pautas llevadas a cabo durante la medición “in situ”. Los resultados obtenidos por simulación se comparan con los obtenidos de las mediciones “in situ”, para estudiar la validación del modelo geométrico. El parámetro acústico elegido para validar el modelo, en un primer momento, será el tiempo de reverberación. Si se consigue una buena validación del modelo geométrico, este puede ser utilizado para realizar predicciones acústicas mediante simulación, cuando un sistema de refuerzo sonoro sea utilizado dentro del recinto. El sistema de refuerzo sonoro ubicado en el recinto sometido a estudio, no ha sido utilizado en el presente proyecto. ABSTRACT. The present projects carry out an acoustic study of enclosure: Rafael Frühbeck Concert Hall, in Burgos, fulfilling the indications demanded by the standard UNE-EN ISO 3382-1:2010 “Measurement of room acoustic parameters – Part 1: Performance spaces. Two acoustics studies are developed on the same enclosure. In first of them, the enclosure is formed for the accomplishment of events such as conferences or congresses, where speech intelligibility is a determining factor. In the second study, the enclosure forms for musical performances like concerts of symphony orchestra or chamber music. In this acoustic configuration, speech intelligibility is not as determining as the correct interpretation and enjoyment of music in audience areas. For both configurations of the enclosure, a statistical processing of the data has been realised with the purpose of obtaining a unique value of each studied acoustic parameter. In this way, the results for both configurations are compared, and the obtained values of each one of the acoustic parameters are evaluated with the purpose of knowing if they are adapted to the acoustic needs demanded by the type of developed event. In addition, a geometric model of the enclosure has been constructed by computer, for both acoustic configurations; making use of the professional software of prediction and acoustical simulation, EASE. An acoustic study is developed on the geometric model by means of simulation, following the rules carried out during the measurement “in situ”. The results obtained by simulation are compared with the obtained ones from the measurement “in situ”, to study the validation of the geometric model. Initially the acoustic parameter chosen to validate the model is Reverberation Time. If a good validation of the geometric model is reached, it can be used to realize acoustic predictions by simulation, when a sound reinforcement system is used within the enclosure. The sound reinforcement system located in the enclosure under study has not been used in the present project.

Estudio acústico y electroacústico para la realización de un musical en el teatro Rialto de Madrid

El propósito de este Proyecto Fin de Carrera es el estudio acústico y electroacústico de la realización del musical “Hoy no me puedo levantar” en el Teatro Rialto de Madrid en 2005. En primer lugar, se realiza una breve introducción histórica, citando sus remodelaciones y comentando la situación actual del recinto. Posteriormente, es analizado el equipo de sonido empleado en el espectáculo a partir de cada uno de los distintos controles de sonido: FOH (Front of Hause), monitores y microfonía inalámbrica. De cada uno de ellos se explican sus principales funciones y los sistemas que los conforman. También se describe la utilización de las cabinas insonorizadas. A continuación, se detallan los sistemas electroacústicos (empleados en el diseño) de la sonorización de dicho musical, que se consideran divididos en las siguientes partes: sistema principal, refuerzos y retardos, efectos y monitores. Además, se detalla el software RMS (Remote Monitoring System), que aporta información del funcionamiento de estos sistemas en tiempo real. Seguidamente, se exponen el equipo, procedimiento y resultados de la medida in situ en el Teatro, aplicando la Norma UNE-EN ISO 3382-2/2008 para obtener el tiempo de reverberación y ruido de fondo. Con el objeto de inicializar la simulación por ordenador, primero se exportan los planos originales de AutoCAD a EASE 4.4, donde se finaliza el proceso de modelar el recinto. Posteriormente, se asignan materiales, áreas de audiencia, puntos de escucha y se ubican los sistemas electroacústicos. Se afina el tiempo de reverberación obtenido en la medida in situ mediante materiales de la base de datos del propio software. También se ajustan los sistemas electroacústicos en el recinto para obtener la ecualización empleada y los niveles de presión sonora directo y total para distintas frecuencias. Una vez finalizados los pasos anteriores, se procede a realizar estudios psicoacústicos para comprobar posibles ecos y el efecto precedencia (empleando retardos electrónicos o delays). Finalmente, se realizan estudios de inteligibilidad, en los que se justifica la Claridad de Voz (C50) y Claridad Musical (C80); el Índice de inteligibilidad del habla (SII), la Pérdida de articulación de consonantes (Alcons) y el Índice de transmisión del habla (STI). Por último se expone el presupuesto del proyecto y del alquiler del equipo de sonido del musical y se exponen las conclusiones del Proyecto Final de Carrera. ABSTRACT. The purpose of this Final Degree Project is the acoustic and electro-acoustic study of the musical “Hoy No Me Puedo Levantar” at Teatro Rialto in 2005 (Madrid, Spain). First of all, a brief review of its history is made, quoting its refurbishments and discussing the current situation of this enclosure. Later, the sound equipment of the show is analyzed through every different sound controls: FOH (Front Of House), monitors and wireless microphones. There is also an explanation about their principal functions and systems, as well as a description of the soundproof cabins. Then, the electro-acoustic systems are detailed and divided in the following parts: main system, boosters and delays, effects and monitors. The RMS software (Remote Monitoring System) is described too, since it gives relevant information of the systems operations in real time. Afterwards, equipment, procedures and results of the measurements are exposed, applying the UNE-EN ISO 3382-2/2008 regulation in order to obtain the reverberation time and background noise of the theatre. With the purpose of initialize the computer simulation, original plans are exported from AutoCad to EASE 4.4., where its modeling process is ended. Materials, audience areas, hearing points and electro-acoustic locations are assigned below. At the same time, reverberation time is tuned up using database materials of the software itself. Also, electro-acoustic systems of the enclosure are adjusted to get the equalization and pressure sound levels of the different frequencies. Once previous steps are finished, psycho-acoustic studies are made to check possible echoes and the precedence effect - using electronic delays -. Finally, intelligibility studies are detailed, where the Voice and Musical Clarities are justified: The Speech Intelligibility Index, the Loss of Consonants Articulation and the Talk Transmission Index. This Final Degree Project ends describing the budget and rent of the sound equipment and the final conclusions.

Use of electropalatography in the treatment of disordered articulation following traumatic brain injury: A case study

Electropalatography (EPG) was used as a biofeedback tool in a case study of a 30-year-old male with disordered articulation following traumatic brain injury (TBI). Based on qualitative measures of the participant's intelligibility, improved articulation of the fricatives /s/ and /integral/ were selected as treatment targets. Therapy was administered three times a week for 5 weeks. Results showed that word and sentence intelligibility increased approximately 10%, and error patterns for lingual articulation indicated that fricative -> stop and other fricative errors decreased considerably. EPG measures for /s/ exhibited a significantly more anterior main focus of articulatory contact post therapy. Consonant durations were significantly longer during weeks 3 and 4, and this finding was associated with the emergence of an articulatory contact pattern with a groove rather than complete closure. This articulatory pattern appeared inconsistently and was found to vary across articulations of /s/ but also within a single consonant production. For /integral/, the amount of contact was significantly reduced post therapy and an increase in duration was noted during week 4, similar to that occurring in the production of /s/. Spatial and timing measures were more variable than in normal speakers of English and indicated a general increase in variability across weeks for both /s/ and /integral/. It was concluded that, although the correct fricative patterns appeared only intermittently during production of the consonants, there seemed to be sufficient information for the listener to be able to classify the sound as a fricative. As a part of an intervention program, visual EPG biofeedback therapy would appear to have a definite role in assisting dysarthric speakers exhibiting difficulties with lingual articulation in understanding their errors, learning how to exploit kinesthetic, and acoustic sources of feedback, and how to make appropriate adjustments in tongue articulation to increase the level of speech intelligibility.

Articulatory function following traumatic brain injury in childhood: A perceptual and instrumental analysis

Primary objective: To investigate the articulatory function of a group of children with traumatic brain injury (TBI), using both perceptual and instrumental techniques. Research design: The performance of 24 children with TBI was assessed on a battery of perceptual (Frenchay Dysarthria Assessment, Assessment of Intelligibility of Dysarthric Speech and speech sample analysis) and instrumental ( lip and tongue pressure transduction systems) assessments and compared with that of 24 non-neurologically impaired children matched for age and sex. Main outcomes: Perceptual assessment identified consonant and vowel imprecision, increased length of phonemes and overall reduction in speech intelligibility, while instrumental assessment revealed significant impairment in lip and tongue function in the TBI group, with rate and pressure in repetitive lip and tongue tasks particularly impaired. Significant negative correlations were identified between the degree of deviance of perceptual articulatory features and decreased function on many non-speech measures of lip function, as well as maximum tongue pressure and fine force tongue control at 20% of maximum tongue pressure. Additionally, sub-clinical articulatory deficits were identified in the children with TBI who were non-dysarthric. Conclusion: The results of the instrumental assessment of lip and tongue function support the finding of substantial articulatory dysfunction in this group of children following TBI. Hence, remediation of articulatory function should be a therapeutic priority in these children.

Treating dysarthria following traumatic brain injury: Investigating the benefits of commencing treatment during post-traumatic amnesia in two participants

Primary objective: The aims of this preliminary study were to explore the suitability for and benefits of commencing dysarthria treatment for people with traumatic brain injury (TBI) while in post-traumatic amnesia ( PTA). It was hypothesized that behaviours in PTA don't preclude participation and dysarthria characteristics would improve post-treatment. Research design: A series of comprehensive case analyses. Methods and procedures: Two participants with severe TBI received dysarthria treatment focused on motor speech deficits until emergence from PTA. A checklist of neurobehavioural sequelae of TBI was rated during therapy and perceptual and motor speech assessments were administered before and after therapy. Main outcomes and results: Results revealed that certain behaviours affected the quality of therapy but didn't preclude the provision of therapy. Treatment resulted in physiological improvements in some speech sub-systems for both participants, with varying functional speech outcomes. Conclusions: These findings suggest that dysarthria treatment can begin and provide short-term benefits to speech production during the late stages of PTA post-TBI.

Informational masking and the effects of differences in fundamental frequency and fundamental-frequency contour on phonetic integration in a formant ensemble

This study explored the effects on speech intelligibility of across-formant differences in fundamental frequency (ΔF0) and F0 contour. Sentence-length speech analogues were presented dichotically (left=F1+F3; right=F2), either alone or—because competition usually reveals grouping cues most clearly—accompanied in the left ear by a competitor for F2 (F2C) that listeners must reject to optimize recognition. F2C was created by inverting the F2 frequency contour. In experiment 1, all left-ear formants shared the same constant F0 and ΔF0F2 was 0 or ±4 semitones. In experiment 2, all left-ear formants shared the natural F0 contour and that for F2 was natural, constant, exaggerated, or inverted. Adding F2C lowered keyword scores, presumably because of informational masking. The results for experiment 1 were complicated by effects associated with the direction of ΔF0F2; this problem was avoided in experiment 2 because all four F0 contours had the same geometric mean frequency. When the target formants were presented alone, scores were relatively high and did not depend on the F0F2 contour. F2C impact was greater when F2 had a different F0 contour from the other formants. This effect was a direct consequence of the associated ΔF0; the F0F2 contour per se did not influence competitor impact.

The intelligibility of cleft palate speech with and without dental prosthesis

This paper discusses a study to investigate the possibility of quantifying and analyzing the speech of cleft palate subjects.

The intelligibility of speech through phonetic transcription

This paper analyzes the phonetic accuracy of both hearing-impaired and normal-hearing individuals’ speech production.

Subjective impressions of child cochlear-implant users: effects of conversational fluency, intelligibility, speech perception, and communication mode

This paper investigates the conversational fluency of young cochlear implant users. The study compares objective measures and subjective impressions of conversation fluency, relates how children’s communication skills influence both objective and subjective measures of conversational fluency, and compares the performance of children who use an oral mode with those who use a total communication mode in everyday conversation.

How the listener's experience influences the rating of the intelligibility of hearing-impaired children's speech

This paper discusses the importance of listener experience as a factor when developing intelligibility measures for hearing impaired children.