Characterization of Ipsilateral Masking Effects in Electric-acoustic Stimulation in Cochlear Implant Users and Influence on Speech Perception PDF Download

Author: Marina Imsiecke
Publisher:
ISBN:
Category :
Languages : de
Pages : 0

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Author: Johannes Benjamin Krüger
Publisher:
ISBN: 9783843953627
Category :
Languages : en
Pages : 0

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Author: Daniel Kipping
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Category :
Languages : en
Pages : 0

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Author: Viral Dinesh Tejani
Publisher:
ISBN:
Category : Auditory masking
Languages : en
Pages : 0

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Improved cochlear implant (CI) designs and surgical techniques have allowed CI patients to retain acoustic hearing in the implanted ear post-operatively. These EAS (electric-acoustic stimulation) CI users listen with a combination of acoustic and electric hearing in the same ear. While electric hearing alone improves speech recognition in quiet, preserved acoustic hearing allows EAS CI users to outperform traditional CI users in speech recognition in noise and demonstrate "speech masking release," an improvement in speech recognition in temporally fluctuating noise relative to steady noise. Masking release is arguably an ecologically valid metric, as listeners often attend to target speech embedded in fluctuating competing speech. Improved speech recognition outcomes have been attributed to the spectral and temporal resolution provided by acoustic hearing. However, the relationship between spectral and temporal resolution and outcomes in EAS CI users is not clear. This study evaluated speech masking release, spectral ripple density discrimination thresholds, and fundamental frequency difference limens (f0DLs) in EAS CI users. Both the ripple and f0DL tasks are thought to measure underlying spectral resolution and temporal fine structure. EAS CI subjects underwent testing in three listening modes: acoustic-only, electric-only, and acoustic+electric. Comparisons across listening modes allowed the benefit provided by acoustic hearing to be quantified. It was hypothesized that speech masking release, spectral ripple density discrimination thresholds, and f0DLs would be poorest with electric-only hearing and would improve in the acoustic-only and acoustic+electric listening modes. This would reflect the benefit of preserved acoustic hearing. It was also hypothesized that speech masking release would correlate with spectral ripple density discrimination thresholds and f0DLs, reflecting the roles of spectral and temporal fine structure cues.

Author: Chhayakanta Patro
Publisher:
ISBN:
Category :
Languages : en
Pages :

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In suboptimal listening environments when noise hinders the continuity of the speech, the normal auditory-cognitive system perceptually integrates available speech information and & ldquo;fills in & rdquo; missing information with help from higher level feedback mechanisms. However, individuals with cochlear implants (CIs) find it difficult and effortful to understand interrupted speech compared to their normal hearing (NH) counterparts. Little is known about CI listeners & rsquo; ability to restore missing speech when they are exposed to challenging listening environments. In this dissertation, three experimental paradigms were used to evaluate listeners & rsquo; ability to utilize their acquired linguistic skills in normal hearing individuals using simulated cochlear implant processing and in individuals with cochlear implants. In the first experiment, listeners & rsquo; abilities to use semantic context when speech was intact or interrupted was evaluated under various spectral resolution conditions. The results suggested that higher level processing facilitates speech perception up to a point but it fails to facilitate speech understanding when speech signals are significantly degraded. In the second experiment, high level processing was investigated using the phonemic restoration effect where sentences were interrupted with and without filler noise at different interruption rates. Both groups failed to show top-down restoration, except the CI users showed some amount of higher level processing at the lowest interruption rate. In the third experiment, a gated word recognition task was used and listeners with CIs required comparatively more acoustic-phonetic information to recognize a word than the NH listeners. In the final experiment, when speech was presented in noise, both groups relied significantly on contextual cues to perceive the speech. Overall, the results from successive experiments indicated CI users rely heavily on contextual cues when they are available. However, when they listen to speech with severe degradations, they may not benefit from semantic context as the incoming speech does not provide enough information to trigger top-down processes. If the signal fidelity (spectral resolution) is improved, their benefit from higher level linguistic feedback processes can be maximized.

Author: Payton Lin
Publisher:
ISBN: 9781267256508
Category :
Languages : en
Pages : 73

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The cochlear implant is a surgically implanted electronic device that can restore partial hearing to a person who is deaf or hearing impaired. This neural prosthesis provides similar functions of the inner ear by electrically stimulating the auditory nerve. Cochlear implant users are able to understand speech in quiet settings, but comprehension is often severely reduced by interfering noise. Our research group seeks to improve cochlear implant performance in loud and noisy environments. We have designed experiments that investigate how the human auditory system processes electric stimulation and separates complex sound interactions into individual sources. Specifically, we look into auditory masking, the process by which the threshold of audibility for one sound is raised by the presence of another sound. The present results show that electric stimulation can mask both electric and acoustic signals under certain conditions. The psychophysical mechanisms of electric masking will be analyzed and contrasted with normal hearing to determine how to optimize electrical parameters and processing strategies.

Author: Tobias Rader
Publisher:
ISBN: 9783843904865
Category :
Languages : de
Pages : 82

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Author: Ruth Y. Litovsky
Publisher: Springer Nature
ISBN: 3030571009
Category : Medical
Languages : en
Pages : 425

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The field of Binaural Hearing involves studies of auditory perception, physiology, and modeling, including normal and abnormal aspects of the system. Binaural processes involved in both sound localization and speech unmasking have gained a broader interest and have received growing attention in the published literature. The field has undergone some significant changes. There is now a much richer understanding of the many aspects that comprising binaural processing, its role in development, and in success and limitations of hearing-aid and cochlear-implant users. The goal of this volume is to provide an up-to-date reference on the developments and novel ideas in the field of binaural hearing. The primary readership for the volume is expected to be academic specialists in the diverse fields that connect with psychoacoustics, neuroscience, engineering, psychology, audiology, and cochlear implants. This volume will serve as an important resource by way of introduction to the field, in particular for graduate students, postdoctoral scholars, the faculty who train them and clinicians.

Author: Pim van Dijk
Publisher: Springer
ISBN: 331925474X
Category : Medical
Languages : en
Pages : 487

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​The International Symposium on Hearing is a prestigious, triennial gathering where world-class scientists present and discuss the most recent advances in the field of human and animal hearing research. The 2015 edition will particularly focus on integrative approaches linking physiological, psychophysical and cognitive aspects of normal and impaired hearing. Like previous editions, the proceedings will contain about 50 chapters ranging from basic to applied research, and of interest to neuroscientists, psychologists, audiologists, engineers, otolaryngologists, and artificial intelligence researchers.​

Author: Cimarron Ludwig
Publisher:
ISBN:
Category : Cochlear implants
Languages : en
Pages : 33

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Book Description
A multitude of individuals across the globe suffer from hearing loss and that number continues to grow. Cochlear implants, while having limitations, provide electrical input for users enabling them to "hear" and more fully interact socially with their environment. There has been a clinical shift to the bilateral placement of implants in both ears and to bimodal placement of a hearing aid in the contralateral ear if residual hearing is present. However, there is potentially more to subsequent speech perception for bilateral and bimodal cochlear implant users than the electric and acoustic input being received via these modalities. For normal listeners vision plays a role and Rosenblum (2005) points out it is a key feature of an integrated perceptual process. Logically, cochlear implant users should also benefit from integrated visual input. The question is how exactly does vision provide benefit to bilateral and bimodal users. Eight (8) bilateral and 5 bimodal participants received randomized experimental phrases previously generated by Liss et al. (1998) in auditory and audiovisual conditions. The participants recorded their perception of the input. Data were consequently analyzed for percent words correct, consonant errors, and lexical boundary error types. Overall, vision was found to improve speech perception for bilateral and bimodal cochlear implant participants. Each group experienced a significant increase in percent words correct when visual input was added. With vision bilateral participants reduced consonant place errors and demonstrated increased use of syllabic stress cues used in lexical segmentation. Therefore, results suggest vision might provide perceptual benefits for bilateral cochlear implant users by granting access to place information and by augmenting cues for syllabic stress in the absence of acoustic input. On the other hand vision did not provide the bimodal participants significantly increased access to place and stress cues. Therefore the exact mechanism by which bimodal implant users improved speech perception with the addition of vision is unknown. These results point to the complexities of audiovisual integration during speech perception and the need for continued research regarding the benefit vision provides to bilateral and bimodal cochlear implant users.