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1
Rumeau, Cécile. „Évaluation de l'efficacité des réflexes de protection de l'oreille par la mesure des produits de distorsion acoustiques chez le rat : développement d'un nouvel outil clinique pour l'homme“. Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0091/document.
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L'audiométrie tonale liminaire est l'outil de référence pour évaluer le fonctionnement auditif, mais c'est un outil subjectif qui mesure des élévations de seuils témoignant de dégâts irréversibles sur le système auditif. La mesure des produits de distorsions acoustiques (PDAs), reflet du fonctionnement cochléaire, permet de dépister précocement des altérations de l'oreille interne causées par le bruit ou certains solvants ototoxiques. A partir d'un paradigme de mesure basé sur un enregistrement continu du PDA cubique (2f1-f2) et une stimulation controlatérale, nous avons pu expliquer, chez le rat, les effets pharmacologiques du toluène. Ce solvant aromatique agirait en particulier sur les centres nerveux impliqués dans le réflexe de protection acoustique de l'oreille moyenne. Devant les résultats obtenus chez l'animal, un prototype d'appareil adapté à l'homme a été mis au point, baptisé EchoScan. L'EchoScan a été testé sur 50 volontaires sains normo-entendant lors d'un premier protocole de recherche clinique pour vérifier la reproductibilité des mesures. Un second protocole a ensuite été conduit pour tester l'outil chez des salariés en entreprise, selon plusieurs conditions d'exposition : témoins non exposés, salariés exposés au bruit, exposés aux solvants, exposés au bruit et aux solvants. Les résultats des deux premières conditions sont présentés dans ce mémoire. Ils confirment la pertinence de la mesure du seuil du réflexe de l'oreille moyenne pour évaluer les effets de l'exposition au bruit. Les résultats des sujets exposés aux solvants évalueront la sensibilité de l'EchoScan dans la détection, voir la caractérisation des effets pharmacologiques de substances chimiques (inclusions en cours). Si l'avenir de l'EchoScan apparaît prometteur en médecine du travail, d'autres applications sont envisagées, comme l'étude des effets pharmacologiques des anesthésiques sur le réflexe de l'oreille moyenneThe pure-tone audiometry is a reference tool to assess auditory function but it is able to measure only threshold elevations showing irreversible damages. Measurement of distortion products oto-acoustic emissions (DPOAEs), reflecting the cochlear function, allows early detection of alterations in the inner ear caused by noise or some ototoxic solvents. From paradigm based on a continuous record of cubic DPOAEs (2f1-f2) and a contralateral stimulation triggering the middle-ear reflex, we could explain, in rats, the pharmacological effects of toluene. This aromatic solvent can act on the centers involved in the middle-ear acoustic protection reflex. With the results obtained in animals, a device adapted to humans has been developed, called EchoScan. The EchoScan was tested on 50 healthy volunteers with normal hearing in a first clinical research protocol to verify in particular the reproducibility of its measurements. A second research protocol was then conducted to test this tool among company employees, according to several exposure conditions: unexposed controls, workers exposed to noise, exposed to solvents, exposed to noise and solvents. The results of the first two conditions are presented in this thesis. They confirm the relevance of the measurement of the middle ear reflex threshold in assessing the effects of noise exposure. The results of subjects exposed to solvents will further evaluate the sensitivity of EchoScan in detection of the pharmacological effects, and even in the characterization of chemical substances exposure (in progress). In the future, EchoScan should be particularly promising in occupational medicine, but other applications are already considered, such as the study of pharmacological effects of anesthetics on the middle ear reflex
2
Hauchere, Marine. „Evaluation des réponses hautes fréquences des produits de distorsion des otoémissions acoustiques et développement du langage au sein d'une population pédiatrique“. Electronic Thesis or Diss., Université Clermont Auvergne (2021-...), 2024. http://www.theses.fr/2024UCFA0186.
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L'audition des hautes fréquences joue un rôle crucial dans la perception et la compréhension du langage oral. Les fréquences élevées, au-dessus de 2000 Hz, sont essentielles pour discerner les consonnes et autres sons aigus qui portent des informations phonétiques importantes, comme les sifflements et les fricatives (par exemple, les sons "s", "sh", "f", "th"). Une perte auditive dans ces hautes fréquences peut ainsi compromettre la clarté du discours et entraîner des difficultés de compréhension. Il est donc crucial de diagnostiquer et de traiter précocement les déficiences auditives pour minimiser leur impact sur les compétences linguistiques et communicationnelles. Une visite médicale obligatoire est effectuée entre cinq et six ans, en grande section de maternelle ou au CP, pour évaluer le développement de l'enfant et détecter précocement les problèmes pouvant affecter les apprentissages. Cependant, l'évaluation auditive repose sur une audiométrie et les fréquences testées couvrent généralement une plage relativement restreinte, comprise entre 1 et 4 kHz. La mesure des otoémissions acoustiques (OAE) et plus particulièrement des produits de distorsion des OAE (DPOAE) permet d'avoir une information sur l'état de l'oreille interne notamment sur la fonctionnalité des cellules ciliées externes. La plage fréquentielle d'enregistrement peut être plus étendue qu'en routine clinique puisqu'elle permet d'enregistrer des réponses pour des fréquences jusqu'à 10kHz. L'objectif de ce projet de thèse était d'enregistrer les OAE hautes fréquences au sein d'une population pédiatrique afin d'avoir un bilan plus complet de l'audition des enfants. Dans l'étude 1, il s'agissait d'évaluer les hautes fréquences au sein d'une population d'ORL pédiatrique consultant pour différents motifs et d'observer les différences de cette mesure selon le type de pathologie. Les résultats des OAE des enfants ayant un retard de langage ont ensuite été analysés et comparés avec les autres groupes afin de mieux caractériser leur profil auditif. Cependant, en l'absence de bilans orthophoniques disponibles, la classification « retard de langage » était basée sur les observations des parents, des enseignants et des professionnels de la santé, sans permettre de caractériser précisément le trouble en termes de type et de sévérité. Suite à l'étude 1, nous avons cherché à déterminer si, au sein d'une population pédiatrique caractérisée sur le plan langagier, notamment à l'aide d'une batterie d'évaluation du langage oral (ELO), il était possible d'identifier des différences auditives par rapport à une population témoin issue d'écoles maternelles et primaires (étude 2). Les résultats ont permis de montrer qu'il était possible d'enregistrer des réponses physiologiques grâce à la mesure des DPOAE malgré un tympanogramme B. Les résultats suggèrent une relation entre déclenchement du reflexe stapédien et les compétences phonologiques. Dans notre population, les enfants présentant des troubles du langage avaient des amplitudes de réponses aux DPOAE plus importantes que les témoins provenant d'écoleHigh-frequency hearing plays a crucial role in the perception and understanding of spoken language. High frequencies, above 2000 Hz, are essential for discerning consonants and other high-pitched sounds that carry important phonetic information, such as whistles and fricatives (for example, the sounds ‘s', ‘sh', ‘f', ‘th'). Hearing loss in these high frequencies can compromise clarity of speech and lead to comprehension difficulties. It is therefore crucial to diagnose and treat hearing impairment early to minimise its impact on language and communication skills.A compulsory medical check-up is carried out between the ages of five and six, in kindergarten or first grade, to assess the child's development and detect problems that could affect learning at an early stage. However, hearing assessment is based on audiometry, and the frequencies tested generally cover a relatively narrow range, between 1 and 4 kHz.The measurement of acoustic otoemissions (OAE) and more specifically OAE distortion products (DPOAE) provides information on the state of the inner ear, in particular the functionality of the outer hair cells. The recording frequency range can be wider than in routine clinical practice, allowing responses to be recorded at frequencies up to 10 kHz.The aim of this thesis project was to record high-frequency OAEs in a paediatric population in order to obtain a more complete picture of children's hearing. In Study 1, the aim was to evaluate high-frequency hearing in a paediatric ENT population consulting for various reasons and to observe the differences in this measurement according to the type of pathology. The OAE results of children with language delay were then analysed and compared with the other groups in order to better characterise their hearing profile. However, in the absence of available speech and language assessments, the ‘language delay' classification was based on the observations of parents, teachers and health professionals, without making it possible to characterise the disorder precisely in terms of type and severity.Following on from Study 1, we set out to determine whether it was possible to identify auditory differences in a paediatric population characterised in terms of language, in particular using an oral language evaluation battery (ELO), compared with a control population drawn from nursery and primary schools (Study 2). The results showed that it was possible to record physiological responses by measuring DPOAE despite a B tympanogram. The results suggest a relationship between stapedial reflex onset and phonological skills. In our population, children with language disorder had larger amplitudes in DPOAE response than control from schools
3
Wathier, Ludivine. „Modifications de l’amplitude du réflexe de l’oreille moyenne après inhalation de solvant. Conséquences physiologiques pour les expositions au bruit“. Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0211/document.
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Le réflexe de l’oreille moyenne (ROM) diminue l’énergie acoustique portée par les bruits riches en basses fréquences et de fortes intensités qui pénètrent dans la cochlée. Son déclenchement bilatéral permet ainsi de protéger la cochlée. La perturbation de ce réflexe par des solvants peut accroître les effets cochléo-traumatisants du bruit, notamment chez les salariés du secteur industriel, où bruit et solvant sont souvent associés. L’objectif principal de ces travaux était d’élaborer un test de criblage capable d’identifier les substances volatiles susceptibles de modifier le réflexe. De plus, le choix des solvants nous a permis d’étudier le mode d’action des solvants sur les neurones impliqués dans l’arc réflexe. Pour cela, des rats Brown Norway anesthésiés ont été exposés par inhalation aux solvants aromatiques choisis selon leur lipophilie (log Kow) et/ou selon leur structure. L’amplitude du ROM a été déterminée grâce à la mesure de l’intensité du produit de distorsion acoustique. Les résultats montrent que les effets des solvants sur le ROM sont conditionnés par les paramètres stéréospécifiques des molécules et non par leur lipophilie. Par ailleurs, l’analyse RMN des microsomes de cerveaux de rats confirme que le toluène n’influence pas la fluidité membranaire. En conclusion, le ROM est un bon outil pour détecter des substances dangereuses pour l’audition en cas de co-exposition avec du bruit. De plus, nous pouvons dire que les solvants aromatiques ont une action neuropharmacologique et/ou cochléotoxique qui peuvent retentir de façon distincte sur l’audition des sujets co-exposés au bruit et à des solvantsThe middle-ear reflex (MER) reduces acoustic energy carried by the high intensity noises rich in low frequencies at entering the cochlea. His bilateral trigger thus protects the cochlea. Disruption of this reflex by solvents can increase cochleo-traumatic effects of noise, especially among industrial workers, where noise and solvent are often associated. The main objective of this work was to develop a screening test capable of identifying the volatile substances that could modify the reflex. Moreover, the choice of solvents allowed us to study the mode of action of solvents on the neurons involved in the reflex circuit. For this purpose, Brown Norway rats were anesthetized and then exposed to aromatic solvents selected according to their lipophilicity (log Kow) and/or their structure. The amplitude of the MER is determined by measuring cubic distortion product oto-acoustic emissions. For that, aromatic solvents appear to act directly on the neuronal targets involved in the acoustic reflex circuit, rather than on membrane fluidity. The affinity of this interaction is determined by stereospecific parameters rather than lipophilocity. Additionally, NMR spectra for brain microsomes confirmed that brain lipid fluidity was unaffected by toluene exposure. In conclusion, the MER can be used to detect hazardous volatiles substances for the hearing when co-exposed to noise. Moreover, this study revealed that aromatic solvents have a neuropharmacological and/or cochleotoxic action that can act separately on the hearing of workers exposed to noise and solvents simultaneously
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Picton, Peter Evan. „Multiple tone pair distortion product otoacoustic emissions“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0002/MQ45426.pdf.
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Tringali, Stéphane. „Contribution de la stimulation magnétique transcranienne répétitive à l’étude de la modulation centrale du fonctionnement cochléaire chez le sujet normo-entendant“. Thesis, Lyon 1, 2011. http://www.theses.fr/2011LYO10289.
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Le système auditif ascendant est constitué d’étages multiples procédant chacun à un traitement complexe du signal, traitement qui est modulé par un système descendant, formant de multiples boucles corticales et sous-corticales de rétroaction : le système efférent auditif. La boucle la plus longue de ce système serait capable de moduler directement le fonctionnement des cellules sensorielles de l’organe périphérique de l’audition. Le but de ce travail était d’étudier pour la première fois chez le sujet sain, l’effet d’une modulation corticale expérimentale sur le fonctionnement périphérique auditif. Nous avons donc recueilli, dans le cadre d’un protocole en double aveugle contre placebo, chez 34 sujets sains, l’activité des cellules ciliées externes de l’organe de Corti (cellules sensorielles directement en contact avec les fibres nerveuses efférentes), par le recueil d’otoémissions acoustiques (OEAs), avant et après stimulation du cortex auditif par une stimulation magnétique transcrânienne répétitive (SMTr). Une diminution de l’amplitude d’un type d’OEA a été obtenue du côté controlatéral à une stimulation du cortex auditif par SMTr à 10 Hz, effet qui ne peut être expliqué seulement par une action non-spécifique liée au bruit de la SMTr mais qui reste extrêmement variable d’un sujet à un autre. De plus, nous avons montré, du côté ipsilatéral à la SMTr, une diminution de l’amplitude des OEAs immédiatement après la SMTr, et uniquement pour les fortes intensités d’utilisation de la SMTr (donc, pour des niveaux de bruit plus importants), reflétant un effet direct du bruit de la SMTr sur les mécanismes cochléaires actifs, effet présent chez nos sujets même en cas de protections auditives de bonne qualitéThe ascending auditory system involves multiples stages where the auditory information is processed and modulated by a top-down influence involving multiple cortico sub-cortical loops: the efferent auditory system. It is hypothesized that the longest loop of this efferent system is able to modulate directly the sensory cells of the peripheral auditory organ. The aim of this work was to study this system, to our knowledge for the first time in healthy humans, and to show a direct cortical influence on the auditory periphery. In a double blind randomized procedure, we recorded, in 34 healthy subjects, the activity of outer hair cells of the organ of Corti (sensory cells, that are in direct synaptic contact with medial efferent fibers), by means of evoked otoacoustic emissions (OAEs), before and after auditory cortex stimulation by repetitive transcranial magnetic stimulation (rTMS). We showed an inhibitory influence of the auditory cortical stimulation by 10 Hz rTMS on OAE amplitudes, predominantly in the ear contralateral to the rTMS, effect that cannot be attributed to a non-specific effect linked to the impulse noise associated with the rTMS technique, but that remains highly variable across subjects. In addition, we showed a decrease in OAE amplitude on the ipsilateral side, immediately after the rTMS session and only for high rTMS intensities (and hence, higher noise levels), that reflect a direct influence of the rTMS noise on the auditory periphery, effect that is present even in well ear-protected subjects
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MacFarlane, Lucy. „Time domain visualisation of distortion product otoacoustic emissions“. Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/393739/.
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Distortion product otoacoustic emissions (DPOAEs) are small sounds believed to be the combination of distortion and reflection energy produced by the cochlea in response to stimulation with simultaneous pure tones. Although used clinically, the exact generation mechanisms associated with DPOAEs are not clear; this is especially the case for 2f2-f1. It is thought that 2f1-f2 and 2f2-f1 DPOAEs contain reflection (R) and distortion (D) energy; the D energy may arise from the region of overlap between the stimulus travelling waves while R energy is reflected from fixed points along the basilar membrane. Cochlear mechanics would suggest the two emissions cannot arise from the same cochlear location; current theories suggest the f2 characteristic place is important to 2f1-f2 while 2f2-f1 is generated more basally. Theories of DPOAE generation have been investigated using various techniques , including time domain investigations. Time domain investigations have often used the phase gradient latency (PGL) technique but this has inherent limitations. An alternative approach is primary tone phase variation (PTPV) - a phase rotation method described by Whitehead et al. (1996) that allows for specific DPOAEs to be extracted. This study has used PTPV to investigate DPOAEs generated by an ISVR developed cochlear model and DPOAEs recorded from 40 normal hearing ears (across two experiments); the overall aim of the study is to learn more about the generation of 2f1-f2 and 2f2-f1 emissions by viewing DPOAEs in the time domain with PTPV. Specific areas of interest are the effect of frequency ratio and primary ramping on the time course of 2f1-f2 and 2f2-f1, and how the time course of emissions varies with stimulus level and fine structure position. It is believed these areas will allow for theories of DPOAE generation to be tested. Output from simulations and recorded emissions supports what is already known and theorised about DPOAE generation. It would appear that 2f1-f2 and 2f2-f1 are the product of multiple components originating from a distributed cochlear source. Temporal behaviour of emissions is influenced by stimulus parameters including level, frequency and ratio. This investigation has contributed to knowledge by studying 2f1-f2 and 2f2-f1 emissions with the PTPV procedure and a novel onset latency estimation technique. Data was collected from a group of normal hearing participants and compared to output of a cochlear model.
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Sung, Lui, und 宋蕾. „Multifrequency tympanometry and distortion product otoacoustic emissions in neonates“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31251110.
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Young, Jacqueline Ann. „Modelling the cochlear origins of distortion product otoacoustic emissions“. Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/175357/.
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Distortion product otoacoustic emissions (DPOAEs) arise within the cochlea in response to two stimulus tones (f1 and f2) at frequencies such as 2f1 − f2 and 2f2 − f1. Each DPOAE derives from two contributing mechanisms within the cochlea: a distributed distortion source and a reflection source. They are used for hearing screening, but a better understanding of their cochlear origin and transmission could potentially extend their clinical application to facilitate objective hearing loss assessment, differential diagnosis of sensorineural hearing losses and improved auditory rehabilitation using hearing aids. In this thesis a numerical model of the human cochlea is developed to study the generation of DPOAEs. It is based on a pre-existing active nonlinear model, the micromechanics of which are carefully re-tuned to simulate the response of the human cochlea to single- and two- tone stimulation. Particular attention is paid to the form and position of the nonlinearity within the model to best match experimental results. The model is also reformulated to verify its stability and ensure computational convergence of the iterative frequency domain solution method. Its predictions are validated against estimated time domain simulations and documented experimental DPOAE measurements. Additionally a novel method is developed for decomposing each frequency component of the cochlear response into forward and backward travelling waves, which is applied to investigate the multiple sources of both the 2f1 − f2 and 2f2 − f1 DPOAEs. The model is used to explain and predict a variety of phenomena observed in experimental DPOAE studies. It also confirms for the 2f1 − f2 emission, that the two source mechanisms are spatially separated and that the only significant reflection contribution is associated with the 2f1 − f2 travelling wave. In contrast, it predicts that the two source mechanisms will overlap in the case of the 2f2 − f1 DPOAE, which can be influenced by reflection of both the primary and 2f2 − f1 travelling waves.
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Sung, Lui. „Multifrequency tympanometry and distortion product otoacoustic emissions in neonates /“. Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22008342.
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Mauermann, Manfred Dieter. „Fine structure in distortion product otoacoustic emissions and auditory perception“. [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=972885544.
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Fung, George Ka-Chung. „The effect of vestibular stimulation on distortion product otoacoustic emissions“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0009/MQ29341.pdf.
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Santiago, de Snyder Soami. „Aging effects on distortion product otoacoustic emissions and speech perception /“. The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487847761306525.
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Kujawa, Sharon Guilds. „Cholinergic antagonists block contralateral suppression of distortion product otoacoustic emissions“. Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186224.
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Presentation of an acoustic signal to one ear can suppress sound-evoked activity recorded at the opposite ear. The suppression appears to be mediated by uncrossed medial olivocochlear (MOC) efferent neurons synapsing with cochlear outer hair cells (OHCs). The cellular and molecular mechanisms underlying this response suppression remain unclear. Recent investigations suggest that the mechanism involves an altered mechanical response of the cochlear partition produced by the MOC neurostransmitter, acetylcholine (ACh), acting on the OHCs. The cholinergic receptor subtypes mediating this efferent control remain unclear. The purpose of this investigation was to provide in vivo pharmacologic characterization of one efferent-mediated response: the contralateral sound suppression of distortion product otoacoustic emissions (DPOAEs). Urethane-anesthetized guinea pigs were used. Perilymph spaces of ipsilateral cochleae were perfused with artificial perilymph (control) and increasing concentrations of nicotinic or muscarinic receptor antagonists or strychnine, a known blocker of MOC activity. Experimental drugs were washed from cochlear perilymph spaces with artificial perilymph. Perfusates were introduced at 2.5 μl/min for 10 min. After each period of perfusion, DPOAEs were recorded before, during and after contralateral wideband noise (WBN) stimulation (70 dB SPL). Pre-perfusion, contralateral WBN attenuated ipsilateral DPOAEs between 1-4 dB. This suppression was blocked dose-responsively by a wide variety of nicotinic and muscarinic receptor antagonists. Strychnine and the nicotinic antagonists alpha-bungarotoxin, kappa-bungarotoxin and curare blocked contralateral suppression at nanomolar concentrations and demonstrated similar potencies. These findings support the hypothesis that a novel nicotinic receptor mediates efferent-induced suppression of DPOAEs. Of the muscarinic antagonists tested (pirenzepine, AF-DX 116, 4-DAMP, atropine), 4-DAMP demonstrated the most potent blockade of contralateral suppression, suggesting either that this efferent control also can be mediated by an M₃ muscarinic receptor, or that the putative novel nicotinic receptor also is blocked by low concentrations of this muscarinic receptor antagonist. Effects were largely reversible and selective to the synapse under study. Furthermore, suppression was not altered by repeated perfusions of the control solution alone. These results provide the first comprehensive, in vivo characterization of cholinergic receptors mediating suppressive effects of efferent activation at the MOC-OHC synapse.
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Jaffer, Taha. „Longitudinal elasticity of the cochlear partition and distortion product otoacoustic emissions“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0015/MQ49749.pdf.
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Tobolski, Carrie J. „Distortion product otoacoustic emissions in individuals with noise exposure and presbycusis“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0020/MQ57332.pdf.
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Hazelbaker, Julie L. „Effect of bone conduction transducer placement on distortion product otoacoustic emissions“. Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1092677782.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xi, 102 p. : ill. (some col.). Advisor: Lawrence Feth, Dept. of Speech & Hearing Science. Includes bibliographical references (p. 97-102).
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Du, Yafei. „The fine structure of distortion product otoacoustic emissions the primary origin /“. Connect to this title online, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1054565073.
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Thesis (Ph. D.)--Ohio State University, 2003.Title from first page of PDF file. Document formatted into pages; contains xii, 92 p.; also includes graphics Includes bibliographical references (p. 87-92). Available online via OhioLINK's ETD Center
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Lizerbram, Jeffrey Kane 1969. „Recording active basilar membrane tuning characteristics using distortion-product otoacoustic emissions“. Thesis, The University of Arizona, 1993. http://hdl.handle.net/10150/278354.
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The objective of this study was to describe ways in which properties of human cochlear travelling waves may be manifested in characteristics of distortion-product otoacoustic emissions (DPOAEs). Four young adults served as subjects. DPOAE magnitude was studied for various frequency-ratio and intensity relationships of the primary stimuli. Results revealed complex relationships between stimulus level (L) and frequency ratios (f). The optimal f2/f1 ratios were highly dependent upon differences between L1 and L2. Maximum distortion product amplitudes were encountered when L2 was smaller than L1 for several stimulus conditions and when f2/f1 ratios were approximately 1.20 (range = 1.05 to 1.25). These observations replicate and extend the findings of prior investigations regarding the optimal parameters associated with the production of DPOAEs, and also provide evidence of the complex, nonlinear events leading to the creation of DPOAEs.
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Fabijanska, Anna, Jacek Smurzynski und Krzysztof Kochanek. „Distortion Product Otoacoustic Emissions in Normal-hearing Patients with Unilateral Tinnitus“. Digital Commons @ East Tennessee State University, 2010. https://dc.etsu.edu/etsu-works/2204.
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De, Waal Rouviere. „The use of artificial neural networks to predict pure tone thresholds in normal and hearing-impaired ears with distortion product otoacoustic emissions“. Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-07292009-125000.
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Ng, Hoi-yee Iris, und 伍凱怡. „Test-retest reliability of distortion product otoacoustic emissions inthe high frequency range“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B27014745.
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Müller, Jörg Alexander. „Diagnostics of the cochlear amplifier by means of distortion product otoacoustic emissions“. kostenfrei, 2008. http://mediatum2.ub.tum.de/node?id=645857.
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Fleenor, L., und Jacek Smurzynski. „Spontaneous and Distortion Product Otoacoustic Emissions and Extended High-frequency Hearing Sensitivity“. Digital Commons @ East Tennessee State University, 2006. https://dc.etsu.edu/etsu-works/2212.
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Smurzynski, Jacek, Krzysztof Kochanek, Adam Pilka und Henryk Skarzynski. „Distortion-product Otoacoustic Emissions in Patients with Low-frequency Sensorineural Hearing Loss“. Digital Commons @ East Tennessee State University, 2007. https://dc.etsu.edu/etsu-works/2194.
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Leonard, Jenifer. „Effects of Supplemental Magnesium on Temporary Threshold Shift: Distortion Product Otoacoustic Emissions“. Scholar Commons, 2003. https://scholarcommons.usf.edu/etd/1416.
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Previous studies have shown that supplemental magnesium administered prior to exposure to noise has an alleviating effect on temporary threshold shift (TTS). These studies have only used audiometric thresholds to demonstrate changes in the auditory system. However, to help determine the effects on outer hair cells (OHCs), a more sensitive measure should be used. The purpose of this study was to determine if supplemental magnesium administration prior to noise exposure has a beneficial effect on acoustic overexposure using a double-blind research design. This was determined by measuring distortion product otoacoustic emissions (DPOAEs) to determine any changes in cochlear OHC function. DPOAE amplitude and signal-to-noise ratio (SNR) measurements were analyzed for two groups of twenty participants (an experimental group and a control group). The experimental group received 150 mg of magnesium gluconate one hour prior to noise exposure. The control group received a placebo pill that was identical in appearance to the magnesium pill. Following noise exposure, the greatest changes in DPOAE amplitude and SNR occurred for the frequencies that were one-half to one octave above the frequency of the stimuli used. The greatest changes in DPOAE measurements were present immediately post TTS-inducing stimulus, with only slight changes present after 30 minutes and no difference between 30 minutes and 60 minutes post-exposure. These results were the same for both groups. It was concluded that this dosage of supplemental magnesium had no apparent protective effect on DPOAEs following intense noise exposure.
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Head, Jodi L. „The Effects of Ear Canal Pressure Variation on Distortion Product Otoacoustic Emissions“. PDXScholar, 1995. https://pdxscholar.library.pdx.edu/open_access_etds/5219.
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The middle ear system is a vital component in the propagation mechanism of otoacoustic emissions. As such, investigation of the effect of variation in middle ear impedance on the measurement of emissions is warranted. Distortion product otoacoustic emissions (DPOAEs) have gained recognition as a means of gaining frequency specific information on auditory function. As the effects of changes in middle ear impedance will vary as a function of frequency, a clear definition of the relationship between middle ear impedance and DPOAE amplitude across the frequency spectrum is needed. Twenty adults (ages 20-37) with normal hearing and normal middle ear function were selected as subjects. Commercially available equipment (Virtual 330) was used to measure the DPOAEs on all subjects. The unit was modified to change canal pressure by coupling the probe to the pressure pump of a clinical acoustic immittance system. One ear from each subject was randomly selected for measurement and each subject was tested under five pressure conditions: +200, O, -200, -300, -400 daPa. The mean frequency of the fl/f2 tone pairs swept from 500 to 8000 Hz. Results indicate that changes in ear canal pressure can effect the amplitude of DPOAEs. Alteration of ear canal pressure resulted in decreased emission amplitude. This effect was found to differ as a function of eliciting frequency with the greatest reduction in amplitude with the mean of the primaries at 500 Hz. Less variation was noted across the ear canal pressures with the higher frequency stimuli. These results are consistent with previous findings reported regarding the effects of impedance changes on spontaneous and transiently evoked otoacoustic emissions.
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Chan, Sze-wen Vanessa. „Occupational hearing loss in Hong Kong : screening with distortion product otoacoustic emission /“. Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B2200838X.
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Heinlen, Krista J. „The effect of body position on distortion product otoacoustic emissions testing in neonates“. College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8582.
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Thesis (Au.D.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Hearing and Speech Sciences. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Newland-Nell, Annette Caroline. „Using distortion product otoacoustic emissions to investigate the efficacy of personal hearing protection“. Diss., Pretoria : [s.n.], 2003. http://upetd.up.ac.za/thesis/available/etd-03032004-104906.
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Chan, Sze-wen Vanessa, und 陳思韻. „Occupational hearing loss in Hong Kong: screening with distortion product otoacoustic emission“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31251067.
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Smurzynski, Jacek, Anna Fabijanska, G. Bartnik, Krzysztof Kochanek und Henryk Skarzynski. „Distortion-Product Otoacoustic Emissions in Normal-hearing Patients with Either Unilateral or Bilateral Tinnitus“. Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etsu-works/2206.
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Pienkowski, Martin. „Evidence for a relationship between the suppression of distortion product otoacoustic emissions and hearing threshold“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0025/MQ50461.pdf.
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Fabijańska, Anna, Jacek Smurzyński, Stavros Hatzopoulos, Krzysztof Kochanek, Grażyna Bartnik, Danuta Raj-Koziak, Manuela Mazzoli et al. „The Relationship Between Distortion Product Otoacoustic Emissions and Extended High-Frequency Audiometry in Tinnitus Patients“. Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/1991.
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BACKGROUND: The aim of this study was to evaluate distortion product otoacoustic emissions (DPOAEs) and extended high-frequency (EHF) thresholds in a control group and in patients with normal hearing sensitivity in the conventional frequency range and reporting unilateral tinnitus.
MATERIAL/METHODS: Seventy patients were enrolled in the study: 47 patients with tinnitus in the left ear (Group 1) and 23 patients with tinnitus in the right ear (Group 2). The control group included 60 otologically normal subjects with no history of pathological tinnitus. Pure-tone thresholds were measured at all standard frequencies from 0.25 to 8 kHz, and at 10, 12.5, 14, and 16 kHz. The DPOAEs were measured in the frequency range from approximately 0.5 to 9 kHz using the primary tones presented at 65/55 dB SPL.
RESULTS: The left ears of patients in Group 1 had higher median hearing thresholds than those in the control subjects at all 4 EHFs, and lower mean DPOAE levels than those in the controls for almost all primary frequencies, but significantly lower only in the 2-kHz region. Median hearing thresholds in the right ears of patients in Group 2 were higher than those in the right ears of the control subjects in the EHF range at 12.5, 14, and 16 kHz. The mean DPOAE levels in the right ears were lower in patients from Group 2 than those in the controls for the majority of primary frequencies, but only reached statistical significance in the 8-kHz region.
CONCLUSIONS: Hearing thresholds in tinnitus ears with normal hearing sensitivity in the conventional range were higher in the EHF region than those in non-tinnitus control subjects, implying that cochlear damage in the basal region may result in the perception of tinnitus. In general, DPOAE levels in tinnitus ears were lower than those in ears of non-tinnitus subjects, suggesting that subclinical cochlear impairment in limited areas, which can be revealed by DPOAEs but not by conventional audiometry, may exist in tinnitus ears. For patients with tinnitus, DPOAE measures combined with behavioral EHF hearing thresholds may provide additional clinical information about the status of the peripheral hearing.
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Lavoie, Kimberly J. „High Frequency Pure Tone Audiometry and High Frequency Distortion Product Otoacoustic Emissions: A Correlational Analysis“. PDXScholar, 2003. https://pdxscholar.library.pdx.edu/open_access_etds/1688.
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Previous studies show that pure tone thresholds are strongly correlated with distortion product otoacoustic emission amplitudes when evaluating the frequency range from 1 to 8 kHz (Avan & Bonfils, 1993). Little is known about correlations between these two measures at higher frequencies from 9-16 kHz. This study compared pure tone thresholds and distortion product otoacoustic emissions (DPOAEs) in this high frequency range for 29 normal hearing subjects ages 18-30. Pure tone thresholds were obtained at 250-16 kHz and distortion product otoacoustic emissions (DPOAE) 2,211-17,675 were measured in the same ears. DPOAE amplitudes were measured using a constant F1/F2 ratio of 1.2, with F2 values ranging from 2,211-17,675 Hz. Data obtained from 50 ears showed a decline in DPOAE amplitude with increasing frequency of the F1 and F2 primary stimulus tones. Behavioral thresholds demonstrated an increase with increasing frequency of the pure tone stimulus. Pearson r-correlation analysis demonstrated a weak relationship between measures. Further investigation revealed that equipment variables prevented accurate readings.
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Smurzynski, Jacek, Anna Fabijanska, Krzysztof Kochanek und Henryk Skarzynski. „Extended High-frequency Audiometry and Distortion Product Otoacoustic Emissions in Normal-hearing Patients with Unilateral Tinnitus“. Digital Commons @ East Tennessee State University, 2009. https://dc.etsu.edu/etsu-works/2201.
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Some tinnitus patients have normal hearing on the conventional audiogram. It has been suggested that the presence of a limited area of damaged outer hair cells (OHCs) with intact inner hair cells, which is not detected on the audiogram, results in unbalanced neural activity between Type I and Type II fibers leading to tinnitus. Distortion product otoacoustic emissions (DPOAEs) provided ambiguous data of OHC function in normal-hearing tinnitus patients when compared to non-tinnitus controls. It is known that hearing loss in the extended high frequency (EHF) region may decrease DPOAEs evoked at lower frequencies. Results of EHF audiometry in tinnitus patients are limited. The aim of the study was to evaluate DPOAEs and EHF thresholds in normal-hearing patients reporting unilateral tinnitus in left ear. Thus, each subject acted as their own control. Data were obtained for 25 subjects with bilateral hearing thresholds 3dB. Median audiometric data showed that thresholds in the left ears were significantly higher than those in the right ears at all four EHFs. Mean DPOAE levels of the left ears were lower than those of the right ears in the frequency range above 1 kHz. Additionally, a paired-comparison test of DPOAE levels of each patient’s right and left ear revealed significant differences at 6, and 8 kHz. The results indicate that: 1. OHC impairment in the most basal region reduces contribution to more apically generated DPOAEs; 2. OHC impairment in a limited area, which may be revealed by DPOAEs but not by conventional audiometry, can contribute to tinnitus generation; and 3. patients with unilateral tinnitus and normal hearing on the conventional audiogram are likely to demonstrate hearing loss in the EHF region.
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Fabijanska, Anna, Jacek Smurzynski, Krzysztof Kochanek, G. Bartnik und Danuta Raj-Koziak. „Distortion Product Otoacoustic Emissions in Normal-hearing Patients with Bilateral Tinnitus and in Non-tinnitus Controls“. Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etsu-works/2207.
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Acker, Leah C. (Leah Christine). „A distortion product otoacoustic emissions (DPOAE) assessment of cochlear function in tinnitus subjects with normal hearing sensitivity“. Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/53201.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 48-50).
Tinnitus, the perception of sound in the absence of an external acoustic source, disrupts the daily life of 1 out of every 200 adults, yet its physiological basis remains largely a mystery. While tinnitus and hearing loss (i.e., elevated pure tone thresholds) commonly co-occur, many people without hearing loss experience tinnitus, raising the question of whether cochlear pathology is always a prerequisite for this percept. This study used distortion product otoacoustic emissions (DPOAEs) to evaluate the cochlear amplifier of 13 tinnitus subjects and 13 non-tinnitus subjects (matched by age, sex, and audiogram) across a broad range of frequencies and intensities. DPOAE magnitudes were measured for at least 52 frequencies (500 Hz
S.M.
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Moepeng, Meshack. „Applicability of Distortion Product Otoacoustic Emissions as a new health surveillance technique for hearing screening in industry“. Diss., University of Pretoria, 2016. http://hdl.handle.net/2263/60391.
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Background: Distortion product otoacoustic emissions (DPOAEs) are a promising screening technique for the early detection of subtle noise induced cochlear function changes.
Objectives: To determine the applicability of DPOAEs as a health surveillance technique for the early detection of noise induced hearing loss (NIHL) in workers at a steel manufacturing industry.
Methods: DPOAEs were recorded in 20 participants with no history of occupational noise exposure and 20 participants exposed to noise in the steel manufacturing industry. Participants were not exposed to noise for at least 48 hours prior to testing. All participants were male with normal audiometric thresholds of ?15 dB HL. The DPOAE presence and response amplitude levels for different frequencies were compared between the two groups. The study further evaluated the short-term test-retest repeatability of DPOAE measurements, and also compared the total test duration of performing DPOAEs to the duration of screening audiometry.
Results: The noise exposed group had statistically significantly lower DPOAE response amplitudes than the control group for all the tested frequencies; (pɘ.001) at 2002 to 4004 Hz, and (p=0.01, p=0.001) at 6348 and 7996 Hz respectively, suggesting more cochlear damage in the noise exposed group due to early outer hair cell damage. DPOAEs showed very good reproducibility, and the average duration of performing a set of DPOAEs was significantly shorter (461 ± 68.2 seconds) than the duration of performing audiometry (591 ± 76.9 seconds), pɘ.001.
Conclusion: DPOAEs appeared to be a sensitive technique in detecting noise induced subtle cochlear function changes. DPOAEs could be used as a health surveillance technique for the early detection of NIHL in the steel manufacturing industry.Dissertation (M Communication Pathology)--University of Pretoria, 2016.
Speech-Language Pathology and Audiology
M Communication Pathology
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Da, Silva Jeferson Jhone. „Développement d'outils pour le suivi non-invasif de la pression intracrânienne par des produits de distorsion acoustiques“. Thesis, Université Clermont Auvergne (2017-2020), 2019. http://www.theses.fr/2019CLFAS010.
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La mesure non invasive de la pression intracrânienne (PIC) est un sujet de recherche depuis des décennies, car les méthodes invasives comportent des risques d’hémorragies et d’infections. La surveillance non invasive par des réponses cochléaires a été suggérée comme étant une mesure fiable. Une des réponses couramment analysées dans ces méthodes est celle des produits de distorsion acoustique (PDA). La mesure du PDA est rapide et simple, car il suffit d'envoyer une stimulation sonore et d'enregistrer la réponse acoustique produit par les cellules ciliées externes à l'aide d'une seule sonde (comme une oreillette) dans le conduit auditif externe. Le déphasage du PDA est le paramètre qui nous permet de surveiller les variations de la PIC. Comme il s'agit d'une mesure relative, il est nécessaire de disposer d'une référence individuelle qui ne devrait pas être modifiée pendant ou entre les mesures. Cependant, les phases sont sensibles au positionnement de la sonde et (même de légères) variations de l'impédance de l'oreille. De plus, l’âge du patient influence les niveaux du PDA qui réduisent généralement avec le vieillissement. Ils sont aussi fragiles et très sensibles à l’environnement acoustique, en particulier le bruit généré par le patient. Le présent travail présente initialement le développement d'une méthode de traitement du signal basée sur l'analyse de la distribution du signal pour l'identification et la réjection automatique des sections bruyantes, afin d'améliorer la robustesse de l'extraction du signal du bruit de fond acoustique. La méthode mise au point a été comparée à la rejection de sections sur la base de seuils déterminés par l'opérateur à l'aide de l'analyse visuelle du spectre du signal (méthode standard). Les résultats ont indiqué un niveau de bruit statistiquement inférieur et des signaux plus stables lors de l'utilisation de la méthode automatique. Une deuxième étude présente une technique de détection du positionnement des sondes et des fuites d'air (AFPS), en utilisant l'analyse de la réponse en fréquence de la pression mesurée dans le conduit auditif externe après une stimulation large bande. Dans cette étude une table d'inclinaison a été utilisée pour induire une légère variation de la PIC dans quatre positions (60°, 0°, -20° et encore 60°) en deux séries de mesures. Nous avons analysé la reproductibilité entre les deux essais et les effets sur les résultats du test du déplacement de la sonde et des fuites d’air quand elles étaient identifiées. Ces analyses ont indiqué que la méthode AFPS est en mesure de classer correctement les signaux en fonction de la présence de fuites d'air ou du déplacement de la sonde. Pour la dernière expérience, les deux techniques (rejection automatique et AFPS) ont été adaptées pour être utilisées en temps réel, permettant d'identifier et de corriger les problèmes éventuels avant ou pendant le test. Nous avons comparé l'appareil modifié et l'appareil commercial en deux séances d'essai, de sorte que chaque appareil a été utilisé pour les deux oreilles. Dans chaque séance, trois tests ont été effectués (T1, T2 et T3), chacun avec cinq valeurs enregistrées pour chacune des trois positions (45°, 0° "position couchée" et -10°). Les trois tests ont été effectués afin de permettre l'analyse de la reproductibilité des mesures, sans et avec l’effet du remplacement de sonde, et sa précision (exprimée par l'écarttype des différences). La méthode AFPS augmente la robustesse, fournissant des valeurs plus cohérentes dans toutes les analyses, surtout en cas de repositionnement de la sonde. La réjection automatique réduit la variabilité entre les cinq mesures prises pour la même position, augmentant ainsi la stabilité et la précision des réponsesNon-invasive measurement of intracranial pressure (ICP) has been a research topic for decades, as invasive methods carry risks of hemorrhages and infections. Non-invasive monitoring by cochlear responses has been suggested as a reliable method. One of the most common solutions considered in these methods is the Distortion Products of Otoacoustic Emissions (DPOAE). The DPOAE measurement is quick and simple, as it only requires sending a sound stimulation and recording the cochlear acoustic response using a single probe (such as an earphone). The DPOAE phase shift is the parameter that allows us to monitor the ICP variations. As this is a relative measure, it is necessary to have an individual reference that should not be changed during or between measurements. In addition, the age of the patient influences the DPOAE levels which generally reduce with aging. They are also fragile and very sensitive to the acoustic environment, especially the noise from the patient. This work first presents the development of a signal processing method based on signal distribution analysis for automatic identification and rejection of noisy sections, in order to improve the robustness of the signal extraction from acoustic background noise. The developed method was compared to the rejection thresholds based on operator visual analysis (standard method). The results indicated a statistically lower noise level and more stable signals when using the automatic method. A second study presents a probe positioning and air leak detection technique (AFPS), based on the frequency response analysis of the pressure measured in the external ear canal after wideband stimulation. In this study, a tilt table was used to induce a slight variation in the ICP in four positions (60°, 0°, -20° and again 60°) into two series of measurements. We analyzed the reproducibility between the two tests and the effects on the test results of probe displacement and air leakage when they were identified. These analyses indicated that the AFPS is able to correctly classify the signals according to the occurrence of air leaks or probe movement. In the last experiment, both techniques (automatic rejection and AFPS) were adapted to be used in real time, to identify and correct any problems before or during the test. We compared the modified device and the commercial device in two test sessions, so that each device was used for both ears. In each session, three tests were performed (T1, T2 and T3), each with five values recorded for each of the three positions (45°, 0° "lying down" and -10°). These three tests were performed to allow the analysis of the reproducibility of the measurements, without and with a probe replacement effect, and its accuracy (expressed as the standard deviation of the differences). The AFPS increases robustness, providing more consistent values in all analyses, especially if the probe is repositioned. Automatic rejection reduces the variability between the five measurements taken for the same position, thus increasing the stability and accuracy of the responses
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Smurzynski, Jacek. „Monitoring the Recovery from a Temporary Threshold Shift Using an Adaptive Procedure and Measurements of Spontaneous and Distortion Product Otoacoustic Emissions“. Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/2209.
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De, Waal Rouviere. „The use of artificial neural networks to predict pure tone thresholds in normal and hearing- impaired ears with distortion product otoacoustic emissions“. Diss., University of Pretoria, 1998. http://hdl.handle.net/2263/26810.
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In the evaluation of special populations, such as neonates, infants and malingerers, audiologist often have to rely heavily on objective measurements to assess hearing ability. Current objective audiological procedures such as tympanometry, the acoustic reflex, auditory brainstem response and transient evoked otoacoustic emissions, however, have certain limitations, contributing to the need of an objective, non¬invasive, rapid, economic test of hearing that evaluate hearing ability in a wide range of frequencies. The purpose of this study was to investigate distortion product otoacoustic emissions (DPOAEs) as an objective test of hearing. The main aim was to attempt to predict hearing ability at 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz with DPOAEs and artificial neural networks (ANNs) in normal and hearing-impaired ears. Other studies that attempted to predict hearing ability with DPOAEs and conventional statistical methods were only able to distinguish between normal and impaired hearing. Back propagation neural networks were trained with the pattern of all present and absent DPOAE responses of 11 DPOAE frequencies of eight DP Grams and pure tone thresholds at 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz. The neural network used the learned correlation between these two data sets to predict hearing ability at 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz. Hearing ability was not predicted as a decibel value, but into one of several categories spanning 10-15dB. Results indicated that prediction accuracy of normal hearing was 92% at 500 Hz, 87% at 1000 Hz, 84% at 2000 Hz and 91% at 4000 Hz. The prediction of hearing-impaired categories was less satisfactory, due to insufficient data for the ANNs to train on. The variables age and gender were included in some of the neural network runs to determine their effect on the distortion product. Gender had only a minor positive effect on prediction accuracy, but age affected prediction accuracy considerably in a positive way. The effect of the amount of data that the neural network had to train on was also investigated. A prediction versus ear count correlation strongly suggested that the inaccurate predictions of hearing-impaired categories is not a result of an inability of DPOAEs to predict pure tone thresholds in hearing impaired ears, but a result of insufficient data for the neural network to train on. This research concluded that DPOAEs and ANNs can be used to accurately predict hearing ability within 10dB in normal and hearing-impaired ears from 500 Hz to 4000 Hz for hearing losses of up to 65dB HL.Dissertation (MCommunication Pathology)--University of Pretoria, 2009.
Speech-Language Pathology and Audiology
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Goel, Eyal. „Noise-induced hearing loss in aerobic class goers : a longitudinal study with pure tone audiometry and distortion product otoacoustic emissions“. Thesis, University of Canterbury. Department of Communication Disorders, 2009. http://hdl.handle.net/10092/2605.
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At-risk hearing conditions in various aerobic classes in different gymnasiums were identified and the hearing of aerobic class goers monitored to provide information for an improved understanding of noise-induced hearing loss. Hearing levels were monitored over time for four comparison groups, including regular attendees of aerobic classes with an average noise level above 85 dBA (“High-Risk” group), regular attendees of aerobic classes with an average noise level below 85 dBA (“Low-Risk” group), non-gym goers attending one “High-Risk” aerobic class with hearing protection (“Control with HP” group), and non-gym goers attending one “High-Risk” aerobic class without hearing protection (“Control without HP” group). Each comparison group consisted of three to five males and three to five females, aged between 18 to 50 years. Measurements of pure-tone audiometry (PTA) and distortion product otoacoustic emissions (DPOAEs) were obtained from before and immediately after participation in one class and 48 hours and 30 days after the initial test. Noise levels in many aerobic classes (77%) were found to be higher than 85 dBA and might have led to signs of hearing deterioration as shown mostly in the reduction of the activities of outer hair cells and sometimes in the shift of hearing threshold. The “High-Risk” group exhibited the largest reduction of DPOAEs amplitudes over time. The “Control without HP” group generally exhibited a larger degree of reduction in DPOAEs amplitudes immediately after exposure as compared with the “Control with HP” group. Measurement of DPOAEs levels appeared to be a more sensitive tool than PTA in detecting early signs of hearing deterioration related to noise exposure.
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Smurzynski, Jacek. „Influence of Monaural Overstimulation in Cochlear Function in Normal- hearing Adults Measured Psychoacoustically and with Spontaneous and Distortion Product Otoacoustic Emissions“. Digital Commons @ East Tennessee State University, 2008. https://dc.etsu.edu/etsu-works/2198.
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De, Waal Rouviere. „Objective prediction of pure tone thresholds in normal and hearing-impaired ears with distortion product otoacoustic emissions and artificial neural networks“. Pretoria : [s.n.], 2000. http://upetd.up.ac.za/thesis/available/etd-07142006-112943.
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Johansson, Magnus. „On noise and hearing loss : Prevalence and reference data“. Doctoral thesis, Linköping : Univ, 2003. http://www.ep.liu.se/diss/science_technology/07/97/index.html.
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Fabijańska, Anna, Jacek Smurzynski, Krzysztof Kochanek, Grazyna Bartnik, Danuta Raj-Koziak und Henryk Skarzynski. „The Influence of High Frequency Hearing Loss on the Distortion Product Otoacoustic Emissions in Tinnitus Subjects with Normal Hearing Thresold (0,25-8kHz)“. Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/1993.
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Aim of the study: To evaluate the influence of high frequency hearing loss (>8000 Hz) on distortion product otoacoustic emissions registered in the frequency range from 0,5 to 8 kHz.
Material and methods: 280 ears with tinnitus and normal hearing (0.25–8 kHz) divided into 3 groups depending on the degree of high frequency hearing loss: group A – hearing threshold up to 20 dB for 10, 12.5, 14 and 16 kHz (68 ears); group B – hearing threshold 25–40 dB HLfor at least one of four EHfs (93 ears); group C – hearing threshold above 40 dB HL for at least one of four EHFs (119 ears). For each group mean audiogram and DP-gram were obtained and statistical analysis was used for comparison across these groups.
Results: Mean DPOAE values in group C were significantly lower in comparison with group A for the frequency range 2–8 kHz, and in comparison with group B were significantly lower for the frequency range 4–8 kHz.
Conclusions: High frequency hearing loss (above 8 kHz) has a relevant influence on distortion product otoacoustic emissions registered at frequencies below 8 kHz in tinnitus patients. The greater is hearing loss above 8 kHz, the lower is DPOAE value below 8 kHz.
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Smurzynski, Jacek. „Influence of Low- and Ultra High-frequency Hearing Thresholds on Distortion Product Otoacoustic Emissions (DPOAEs): An Attempt to Separate DPOAE Generation Mechanisms“. Digital Commons @ East Tennessee State University, 2010. https://dc.etsu.edu/etsu-works/2205.
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Ferrence, Kimberly Diane. „Studying the effects of changing experimental parameters on the medial olivocochlear efferent fibers and outer hair cell activity by measurement of distortion product otoacoustic emissions“. [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0015383.
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Marcrum, Steven [Verfasser], Werner [Akademischer Betreuer] [Gutachter] Hemmert und Peter [Gutachter] Kummer. „Optimal Primary Tone Levels in Distortion Product Otoacoustic Emissions and the Role of Middle Ear Transmission / Steven Marcrum ; Gutachter: Peter Kummer, Werner Hemmert ; Betreuer: Werner Hemmert“. München : Universitätsbibliothek der TU München, 2017. http://d-nb.info/114756583X/34.
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Köstlin, Nicole. „Objective measures of function of the peripheral auditory system in adults with diabetes mellitus type 1 and type 2 : a systematic review and meta-analysis“. Diss., University of Pretoria, 2016. http://hdl.handle.net/2263/59163.
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Objective: This study aimed to systematically review and analyse the available peer-reviewed literature reporting on the results of distortion product otoacoustic emissions (DPOAEs), transient evoked otoacoustic emissions (TEOAEs) and click auditory brainstem responses (c-ABRs) in adults with type 1 and type 2 diabetes mellitus (T1DM and T2DM).
Method: A comprehensive literature search was conducted across three electronic databases to identify English; peer-reviewed articles that included results of OAEs (DPOAEs and TEOAEs) and c-ABR tests in adult subjects with DM. Articles were selected according to predetermined selection criteria and critically reviewed independently by two researchers.
Results: 15 studies met the inclusion criteria for the systematic review while nine articles qualified for inclusion in the meta-analysis. DPOAE studies reported significantly reduced amplitudes with only one study reporting larger amplitudes. Abnormal TEOAEs were reported in all TEOAE studies, although these abnormalities were not always significant. Significantly delayed c-ABRs were reported in all ABR studies. Analysis of c-ABR mean wave latencies identified longer latencies for DM subjects, particularly for wave III and V, as well as for IPL I-III and I-V.
Conclusions: Subjects with T1DM and T2DM may present with clinical or subclinical impairment of the cochlear outer hair cells and both the peripheral and central auditory pathway.Dissertation (MA)--University of Pretoria, 2016.
Speech-Language Pathology and Audiology
MA
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