PURPOSE: To describe the need for and perceived outcomes of group meetings for adult cochlear implant recipients (ACIR). METHOD: The research study was conducted in two phases, namely a quantitative descriptive phase where data was collected by means of a questionnaire, and a qualitative deepening phase where data was collected by means of focus group discussions. Thirty-six ACIR completed questionnaires in order to determine the need for and specific requirements for group meetings. The outcomes of phase one contributed to the establishment of group meetings for ACIR. After four consecutive group meetings, focus group discussions were conducted (nine participants) in order to describe the perceived outcomes of group meetings. RESULTS: Participants expressed an evident need to attend group meetings and logistical requirements and preferences were established. After participation in group meetings, benefits in terms of psychological and emotional support, acceptance, understanding and improvement in social skills and confidence were reported. The opportunity to offer and receive support created a sense of empowerment for participants. CONCLUSION: The establishment of much needed group meetings benefited ACIR to a great extent. ACIR reported positive outcomes with regards to improved assertiveness and selfperceived quality of life as a result of their group meeting attendance. / Dissertation (MA)--University of Pretoria, 2014. / lk2014 / Speech-Language Pathology and Audiology / MA / Unrestricted

The aim of this study was to determine which land line telephone and/or mobile/cellular telephone will enable an individual with a cochlear implant to achieve the best speech discrimination scores. Objective measurements and the subjective experience of the individual were used. The literature review provided an overview on the telephone abilities of individuals fitted with cochlear implants. In this study three factors, the quality of the telephone, the speaker's voice and different speech-coding strategies, were discussed and examined, in order to explore and explain the technical difficulties commonly experienced by this population regarding the successful use of a telephone. Data regarding various telephones and the influence different voice-types has on the telecommunication abilities were obtained through the execution of the methodology. Telephone abilities on five different telephones were assessed. Ten participants, four females and six males, fitted with the ESPrit 22, ESPrit 24 and ESPrit 3G Nucleus cochlear implants were used. The Central Institute for the Deaf (CID) open-set sentences were used and data was statistically analysed using a split plot design. Significant differences between different types of telephones were found. The results also suggested that different voice types have an impact on these individual's ability to use a telephone independently. Possible reasons such as different coding strategies, technical interference and quality of voices were discussed. Recommendations for developing rehabilitation programs, to obtain successful telephone competence for these individuals, were made and discussed. The study aimed to empower technologists working in this field to actively take note of the need for development and continuous research regarding various telephones. These telephones should enable more individuals fitted with cochlear implants to receive the maximum speech discrimination with the minimum interference. The findings of this study should encourage future research regarding this topic. A more extensive range of telephones should be used and compared to the findings in this study. / Dissertation (M (Communication Pathology))--University of Pretoria, 2006. / Speech-Language Pathology and Audiology / Unrestricted

L'implantation cochléaire reste à ce jour le seul moyen capable de restaurer la perception auditive chez les personnes présentant une surdité sévère ou profonde en échec d'appareillage conventionnel. Son principe repose sur la stimulation électrique directe des neurones auditifs de la cochlée par un faisceau d'électrode inséré dans l'oreille interne. Malgré les progrès réalisés dans le manufacturage des électrodes et dans la technique chirurgicale, le geste d'insertion du faisceau d'électrode demeure traumatique. Ce traumatisme est souvent responsable de la perte de l'audition résiduelle sur les fréquences graves et d'une réaction inflammatoire conduisant à une cicatrisation fibreuse. Cette réaction fibreuse est délétère à la fois pour le fonctionnement de l'implant, car augmentant l'impédance des électrodes, mais aussi pour l'audition résiduelle lorsqu'elle est préservée, limitant ainsi les possibilités de stimulation hybride électro-acoustique. Aussi les recherches actuelles tendent à réduire cette fibrose par des moyens pharmacologiques limités, utilisant un corticoïde (dexaméthasone), sans pour autant que son efficacité n'ait été démontrée de manière formelle in vitro ou in vivo. En outre, les cibles moléculaires visées lors de la réaction inflammatoire et fibrotique dans la cochlée n'étant pas clairement identifiées, il est difficile de savoir si cette approche thérapeutique est la plus adaptée. Dans ce travail nous avons donc mis au point des modèles in vitro de culture de tranche de cochlée et d'explant cochléaire de rat pour tester l'efficacité antifibrotique et la toxicité de plusieurs drogues, dont la dexaméthasone, mais aussi l'aracytine, antimitotique non ototoxique et d'utilisation sûre au contact du système nerveux central. Entre nos mains, il apparaît que la stratégie antimitotique par application d'aracytine était plus efficace contre la fibrose et moins toxique pour les cellules sensorielles que la dexamethasone. Dans une seconde partie de ce travail, nous avons utilisé deux modèles in vivo de fibrose cochléaire, à savoir : l'induction d'une labyrinthite immune à Keyhole Limpet Hemocyanin et l'implantation chronique d'un corps étranger intra-cochléaire. A nouveau, l'aracytine délivrée par pompe osmotique intracochléaire permettait de réduire significativement la fibrose dans le modèle de labyrinthite alors que l'effet de la dexamethasone n'était pas significatif. De même la préservation de l'audition était statistiquement meilleure dans le groupe des animaux traités par antimitotiques. Aussi seule l'aracytine a été testée dans l'autre modèle de corps étranger intracochléaire. Elle permettait également de réduire la fibrose observée dans la cochlée, sans effet toxique sur les neurones auditifs. Si la préservation de l'audition était impossible dans le groupe contrôle, l'audition sur les basses fréquences était conservée chez les animaux traités par aracytine. Enfin, les seuils de stimulation électrique capables de provoquer une réponse électrophysiologique par le potentiel évoqué auditif étaient significativement inférieurs dans le groupe traité par aracytine. Ainsi, nous avons pu montrer qu'une stratégie antimitotique était capable d'inhiber efficacement la fibrose dans la cochlée in vitro et in vivo, et ce avec une efficacité supérieure à la dexaméthasone. Nous recommandons donc d'envisager en pratique clinique l'utilisation de l'aracytine pour prévenir la fibrose cochléaire. De plus, ce travail souligne l'intérêt de mieux décortiquer les voies cellulaires conduisant à l'inflammation et à la fibrose cochléaire, de sorte à déterminer les meilleures cibles et molécules candidates. Ces mêmes molécules pourront être testées sur les modèles que nous avons mis au point afin de proposer de nouvelles alternatives thérapeutiques à la prévention de la fibrose cochléaire. / Cochlear implantation is the only treatment capable of restoring the auditory pathways in patient suffering from severe to profound hearing loss with poor benefit from hearing aids. Its functioning relies on direct electric stimulation of primary auditory neurons through an electrode array inserted into the cochlea.Despite the advances in electrode design and surgical technique, the act of inserting the electrode array is still traumatic. These traumas result in the loss of residual hearing in low frequencies and provoke an inflammatory reaction leading to fibrous scarring. This fibrous reaction is deleterious to not only the implant performance by increasing the impedance of the electrodes, but also the preserved residual hearing which limit the possibilities of hybrid electro-acoustic stimulation.Current researches aim at limiting this fibrosis by drug application, such as corticosteroids. Therefore dexamethasone is frequently used, but its effectiveness has been only demonstrated formally in vitro or in vivo. Furthermore, the molecular targets set in the fibrotic and inflammatory reaction in the cochlea are not clearly identified, and it is unclear whether this therapeutic approach is best suited.In this study we have developed in vitro models of rat cochlear slice and cochlear explants culture to test the antifibrotic efficacy and toxicity of various drugs, including dexamethasone, but also aracytine, an antimitotic drug with very low ototoxicity which is safely used in contact with the central nervous system. In our hands, it appears that antimitotic aracytine is more effective against fibrosis and less toxic to the sensory cells than the anti-inflammatory drug dexamethasone.In the second part of this study, we used two in vivo models of cochlear fibrosis namely the KLH(keyhole limpet hemocyanin)-induced sterile labyrinthitis and the foreign-body-induced chronic labyrinthitis. Again, the intracochlear fibrosis in the model of KLH-induced labyrinthitis was signticantly reduced by the osmotic pump with aracytine, while the effect of dexamethasone was not significant. Also the preservation of the hearing was statistically better in the group of animals treated with this antimitotic drug. Consequently, aracytine was the only drug tested in the other model of foreign-body-induced labyrinthitis. Again, aracytine reduced fibrosis in the cochlea, without any toxic effects on auditory neurons. While the preservation of the hearing was not achieved in the control group, the low frequencies hearing was preserved in animals treated with aracytine. Finally, the thresholds of electrical stimulation eliciting auditory brainstem response recordings were significantly lower in the treated group by aracytine.Thus, we have shown that an antimitotic strategy was able to inhibit fibrosis effectively in the cochlea in vitro and in vivo, and this with a greater efficiency than dexamethasone. We therefore recommend considering in clinical practice the use of aracytine to prevent cochlear fibrosis. In addition, this study stresses the importance of analyzing the cellular pathways of cochlear inflammation and fibrosis, in order to determine the best targets and candidate molecules. These molecules could be tested on the models that we have developed in order to offer new therapeutic options to prevent cochlear fibrosis.

There has been a great amount of debate between the medical community and the Deaf community regarding cochlear implants. Indeed, some factions of the Deaf community have reacted with hostility to the development of the technology and have protested its implementation. Existing literature examines Deaf individuals' perceptions of cochlear implants, however there has been a significant lack of academic attention paid to the hearing children of deaf adults (codas). As children of deaf parents, codas grow up simultaneously inhabiting two worlds: the Deaf world of their parents and the hearing world of their peers. It is codas' unique position and loyalties between the Deaf world and the hearing world that make them important to the cochlear implant debate. This study investigates codas' perceptions of cochlear implantation using standard ethnographic methods, including in-depth, open-ended interviewing with codas, and immersion in the research population through ongoing participant-observation at a deaf school. The findings suggest that (1) codas' interstitial identity impacts their perceptions of and attitudes towards cochlear implantation and (2) cochlear implants have contributed to a refinement of Coda identity in relation to the Deaf community.

Orientador: Ana Cláudia Moreira Almeida-Verdu / Resumo: A deficiência auditiva sensorioneural, de grau severo-profundo, bilateral e pré-lingual pode comprometer a aquisição de repertórios verbais. O implante coclear (IC) é um dispositivo auditivo que habilita o acesso aos sons da fala e permite a aprendizagem de habilidades de ouvinte e de falante. Estudos entre a Fonoaudiologia e a Análise do Comportamento têm adotado o modelo das relações de equivalência e investigado as condições de ensino sob as quais essa população aprende as habilidades auditivas e as relações que o ouvir estabelece com o falar, de palavras às sentenças. O procedimento de matching to sample (MTS) tem sido utilizado para ensinar relações condicionais entre estímulos. Procedimentos associados ao MTS minimizam a ocorrência de erros durante a aprendizagem do reconhecimento auditivo de sentenças, como o fading out. O objetivo geral desta pesquisa foi controlar o efeito do procedimento de fading out no ensino de discriminações condicionais entre sentença de quatro termos ditadas e figuras de ações, de modo a verificar qual rotina de ensino (fading blocado ou fading randomizado) é mais eficaz. Foram avaliados também os efeitos desses procedimentos sobre a formação de classes de estímulos equivalentes, a precisão da fala na nomeação de figuras e os desempenhos recombinativos. Participaram duas alunas, com idade entre sete e nove anos, com deficiência auditiva sensorioneural, bilateral, de grau moderado a profundo, e usuárias de IC. As sentenças foram organizadas em ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Sensorineural hearing loss, severe-profound, bilateral and pre-lingual, can compromise the acquisition of verbal repertoires. The cochlear implant (CI) is an auditory device that enables access to speech sounds and allows the learning of listening and speaking skills. Studies between Speech-Language Pathology and Behavior Analysis have adopted the equivalence relations model and investigated the teaching conditions under which this population learns the auditory skills and the relationships that listening establishes with speaking, from words to sentences. The matching to sample (MTS) procedure has been used to teach conditional relations between stimuli. Procedures associated with the MTS minimize the occurrence of errors during the learning of auditory recognition of sentences, such as fading out. The general objective of this research was to control the effect of the fading out procedure in the teaching of conditional discriminations between sentences of four dictated terms and action figures, in order to verify which teaching routine (blocked fading or randomized fading) is more effective. The effects of these procedures on the formation of equivalent stimulus classes, the accuracy of speech in the naming of figures and the recombinative performances were also evaluated. Two students participated, aged between seven and nine years, with bilateral sensorineural hearing loss, of moderate to profound degree, and CI users. The sentences were organized in two matrices (Sets 1 ... (Complete abstract click electronic access below) / Mestre

This thesis focuses on simulation modelling of a piezoelectric MEMS filter, which may be used as a part of cochlear implant. A model of this filter is created in the programme ANSYS. A research on experimental cochlear implants and materials suitable for this application is also included.

L’implant cochléaire, la neuroprothèse la plus répandue et la plus réussie de nos jours, permet à des sujets sourds profonds de récupérer une perception auditive permettant une compréhension du langage. Bien que les technologies et les processeurs actuels aient grandement évoluées depuis ces vingt dernières années, la stratégie optimale pour coder l'intensité sonore dans l’implant n’a pas encore été trouvée. L'accès à des indices physiologiques est difficile chez le patient humain alors qu’il est relativement simple chez l’animal. Le but de cette thèse était de développer un modèle animal (cobaye) d'implantation cochléaire et d'étudier la réponse du système auditif à différentes stratégies de stimulation. Les réponses du nerf auditif et des neurones du cortex auditif primaire ont été obtenues lors de stimulations via un implant cochléaire simplifié.Nous avons observé que l’importante variabilité inter-individuelle dans l’efficacité de 2 stratégies (augmentation d’amplitude vs. de durée des pulses électriques) à augmenter les réponses du nerf auditif se répercute au niveau du cortex auditif. Les tests de nouvelles formes de pulses (pulses asymétriques ou en rampes) sur les réponses des neurones corticaux suggèrent que ce type de pulses permettrait de réduire l’étendue corticale activée par la stimulation électrique même aux charges les plus élevées. Là aussi, une importante variabilité inter-individuelle a été observée. Cela a conduit à ce que les activations corticales les plus proches de l’activation normalement observée par des sons purs, soient obtenues soit avec une forme de pulses soit une autre. Cette thèse prône donc qu’il est indispensable d’avoir accès à de nombreuses stratégies de stimulation sur chaque sujet afin de choisir celle la plus adaptée pour un patient donné. / Cochlear implant, the most successful neuroprosthesis allows deaf subjects to recover auditory perception and speech intelligibility. Over the last decades, the technology and the coding strategies in cochlear implants have been largely improved but the optimal strategy for coding loudness is still problematic. Human studies face a lot of restrictions especially regarding the collection of electrophysiological events. The primary goal of this thesis is to develop an animal model (guinea pig) of implantation and to study the auditory system's responses for different strategies for coding sound loudness (increase in amplitude vs. duration of electrical pulses). We studied the responses of the auditory nerve and primary auditory cortex obtained with electrical stimulation delivered through a simplified cochlear implant.We observed that the large inter-individual variability in the efficacy of these two classical strategies for increasing auditory nerve responses is reflected in the auditory cortex. Testing new forms of pulses (asymmetric pulses or ramped pulses) suggests that this type of pulses would reduce the evoked responses of cortical neurons even at the highest injected charges. Again, a large inter-individual variability was observed. As a consequence, for each animal, the cortical response the closest from the activation normally observed with pure tones, is obtained either with one form of pulses or another. This thesis advocates that it is essential to have access to several stimulation strategies on each subject in order to choose the most appropriate for a given patient.

Children with residual hearing have become eligible for consideration as CI candidates in some pediatric programs because of the positive clinical research outcomes of cochlear implant (CI). However, decision-making about CIs for children with residual hearing is difficult for parents because they experience uncertainty when their children show auditory benefits and are developing language through hearing aids (HAs). Clinicians may be uncomfortable recommending CI for these children due to variability in audiometric candidacy criteria in individual clinical practice. However, there is very limited information about the CI decision-making process and needs to assist the parents of these children and practitioners. We conducted a comprehensive study to better understand and support the CI decision-making experiences of families and practitioners. The objectives of our study were to: 1) explore the clinical characteristics and outcomes of children with residual hearing who received CIs, 2) summarize the evidence about the benefits and risks of CIs compared to HAs in children with residual hearing, and 3) explore the decision-making process and needs for children with residual hearing from the perspective of parents and practitioners. This research project combined quantitative and qualitative research designs. A retrospective chart review was conducted to address the first objective. Data on the clinical characteristics of children with residual hearing were extracted from medical charts from a tertiary care pediatric CI center in Ottawa, Canada. A systematic review was performed on the benefits and risks of CIs versus HAs for children with residual hearing to address the second objective. The third objective was addressed through two sub-studies. The first sub-study involved qualitative semi-structured interviews. A total of 12 parents participated in individual interviews. In the second sub-study, 17 practitioners at a pediatric CI center in Ottawa, Canada, and specialized teachers of the deaf and hard of hearing at local school boards were recruited, and four focus groups and one individual interview were conducted. This study showed that a total of 100 of 389 (25.7%) children who received CIs from 1992 to 2018 at the Children's Hospital of Eastern Ontario (CHEO) had residual hearing, representing more than half the children who were implanted in the last two years covered by the study. As documented in our study, overall, children with residual hearing demonstrated benefits in auditory functioning following cochlear implantation. Approximately 70% of these children achieved open-set word perception scores of 80% or more post-CI. In the systematic reviews, a total of 3265 citations were identified, of which eight studies met inclusion criteria. The articles consisted of four moderate and two weak quality pre-post cohort studies and two weak quality cross-sectional studies. The systematic review confirmed that children with CIs showed significantly better speech perception scores than those with HAs. Limited evidence of improvement in auditory performance and non-significant improvement in speech intelligibility was found. Two aspects of social-emotional functioning (hyperactivity/inattention and pro-social behaviour) showed significant improvement with CIs. Our finding also contributes new information about the loss of residual hearing and device use. Four studies provided data on risks following CIs; a total of 16 of 43 (37.2%) children showed loss of residual hearing and 14.0% (8/57) of children had discontinued or limited use of their CI or HA. The qualitative interviews revealed that both parents and practitioners identified child’s everyday functioning as an important factor that influenced their decision-making. It was clear through the qualitative research with parents that they held a strong preference for child’s inclusion into hearing society. Spoken communication was a core value for the parents of these children and some parents expressed high expectations that their children’s hearing would become ‘normal’. We found that practitioners primarily supported parental decision-making by providing information on the practical aspects of the benefits and risks of CIs. Overall parents were satisfied with the decision-making process and decision support from practitioners. However, parents stressed the importance of receiving more personalized information that considered their specific concerns, values and preferences related to their child and family’s circumstances. Practitioners also noted that more research among children with residual hearing is needed to guide parental CI decision-making. To our knowledge, the findings from this dissertation are the first to examine decision-making for children with residual hearing. Our study contributes new information about the characteristics of children receiving CIs, the potential benefits and risks for children with residual hearing, and decision-making needs from the perspectives of families and practitioners. In addition, our research is a useful first step in understanding what families need to make better decisions to assist in the CI decision-making process for this specific population.

This work concerns the inclusive education of children with cochlear implants (CI). The theoretical part is devoted to the introduction to the issue of hearing impairments and their diagnostics. It provides informations on the issue of the cochlear implant and its history. It describes companies producing cochlear implants and implantation of their products in specific hospitals in the Czech Republic. The last theoretical chapter focuses on the education of children with CI, supporting measures and it contains selected studies about teachers' opinions on the inclusion of these children. The practical part of the work was carried out in the form of an online questionnaire survey inspired by one of the studies (Dulčić a Bakota, 2009) mentioned in the theoretical part. The research was enriched by open and semi-closed questions to obtain qualitative data, in addition to the quantitative part. The basis of the research was to find: whether teachers welcome the inclusion of children with CI. Further aims of the research were to find: how teachers are informed about the cochlear implant, what are the opinions of interviewed teachers on the inclusion of children with CI into their schools and how interviewed teachers are experienced with these children. Research has shown that the vast majority of teachers fully...

A model that can accurately predict speech recognition for cochlear implant (CI) listeners is essential for the optimal fitting of cochlear implants. By implementing a CI acoustic model that mimics CI speech processing, the challenge of predicting speech perception in cochlear implants can be simplified. As a first step in predicting the recognition of speech processed through an acoustic model, vowel perception in severe speech-shaped noise was investigated in the current study. The aim was to determine the acoustic cues that listeners use to recognize vowels in severe noise and make suggestions regarding a vowel perception predictor. It is known that formants play an important role in quiet, while in severe noise the role of formants is still unknown. The relative importance of F1 and F2 is also of interest, since the masking of noise is not always evenly distributed over the vowel spectrum. The problem was addressed by synthesizing vowels consisting of either detailed spectral shape or formant information. F1 and F2 were also suppressed to examine the effect in severe noise. The synthetic stimuli were presented to listeners in quiet and signal-to-noise ratios of 0 dB, -5 dB and -10 dB. Results showed that in severe noise, vowels synthesized according to the whole-spectrum were recognized significantly better than vowels containing only formants. Multidimensional scaling and FITA analysis indicated that formants were still perceived and extracted by the human auditory system in severe noise, especially when the vowel spectrum consisted of the whole spectral shape. Although F1 and F2 vary in importance in listening conditions of quiet and less noisy conditions, the role of the two cues appears to be similar in severe noise. It was suggested that not only the availability formants, but also details of the vowel spectral shape can help to predict vowel recognition in severe noise to a certain degree. / Dissertation (MEng)--University of Pretoria, 2010. / Electrical, Electronic and Computer Engineering / unrestricted