Cochlear Limited

About: Cochlear Limited is a company organization based out in Sydney, New South Wales, Australia. It is known for research contribution in the topics: Cochlear implant & Hearing loss. The organization has 1290 authors who have published 1479 publications receiving 33109 citations. The organization is also known as: кохлеарные Americas & COCHLEAR LIMITED.

Excitation characteristic of a bipolar stimulus for broadband stimulation in measurements of electrically evoked auditory potentials.

Abstract: Objective The aim of this study was to determine the optimum electrical stimulation mode for the measurement of electrically evoked potentials. To quantify the broadband excitation electrically evoked compound action potentials were recorded in cochlear implant recipients. The full width half maximum was determined for spread of excitation along the electrode array. Design Prospective clinical study. Study sample The study sample consisted of 20 adult cochlear implant users. Results The applied alternating, intracochlear stimulation mode leads to neural excitation along approximately 80% of the length of the electrode array. The median of the full width at half maximum values covered the range of 18 electrodes on the implant array. Conclusion The bipolar, alternating, and intracochlear stimulation mode would provide a sufficient, broadband excitation of the spiral ganglion to measure electrically evoked auditory potentials.

Speech recognition by a deaf-blind multichannel cochlear implant patient.

Abstract: A case study of the first deaf-blind patient implanted with a Nucleus 22 channel cochlear prosthesis is presented. The patient's preimplant evaluation data, using a powerful hearing aid and vibro-tactile device, are compared with results obtained 8 months postimplant. Preimplant testing indicated no consistent response to sound. Postimplant testing showed ability to comprehend some open set speech with hearing alone through the cochlear implant including ability to utilize the telephone without a code system. The postimplant data suggest potential benefit for other postlingually deaf-blind individuals from multichannel cochlear stimulation.

Music Is More Enjoyable With Two Ears, Even If One of Them Receives a Degraded Signal Provided By a Cochlear Implant.

Abstract: OBJECTIVES Cochlear implants (CIs) restore speech perception in quiet but they also eliminate or distort many acoustic cues that are important for music enjoyment. Unfortunately, quantifying music enjoyment by CI users has been difficult because comparisons must rely on their recollection of music before they lost their hearing. Here, we aimed to assess music enjoyment in CI users using a readily interpretable reference based on acoustic hearing. The comparison was done by testing "single-sided deafness" (SSD) patients who have normal hearing (NH) in one ear and a CI in the other ear. The study also aimed to assess binaural musical enjoyment, with the reference being the experience of hearing with a single NH ear. Three experiments assessed the effect of adding different kinds of input to the second ear: electrical, vocoded, or unmodified. DESIGN In experiment 1, music enjoyment in SSD-CI users was investigated using a modified version of the MUSHRA (MUltiple Stimuli with Hidden Reference and Anchor) method. Listeners rated their enjoyment of song segments on a scale of 0 to 200, where 100 represented the enjoyment obtained from a song segment presented to the NH ear, 0 represented a highly degraded version of the same song segment presented to the same ear, and 200 represented enjoyment subjectively rated as twice as good as the 100 reference. Stimuli consisted of acoustic only, electric only, acoustic and electric, as well as other conditions with low pass filtered acoustic stimuli. Acoustic stimulation was provided by headphone to the NH ear and electric stimulation was provided by direct audio input to the subject's speech processor. In experiment 2, the task was repeated using NH listeners who received vocoded stimuli instead of electric stimuli. Experiment 3 tested the effect of adding the same unmodified song segment to the second ear, also in NH listeners. RESULTS Music presented through the CI only was very unpleasant, with an average rating of 20. Surprisingly, the combination of the unpleasant CI signal in one ear with acoustic stimulation in the other ear was rated more enjoyable (mean = 123) than acoustic processing alone. Presentation of the same monaural musical signal to both ears in NH listeners resulted with even greater enhancement of the experience compared with presentation to a single ear (mean = 159). Repeating the experiment using a vocoder to one ear of NH listeners resulted in interference rather than enhancement. CONCLUSIONS Music enjoyment from electric stimulation is extremely poor relative to a readily interpretable NH baseline for CI-SSD listeners. However, the combination of this unenjoyable signal presented through a CI and an unmodified acoustic signal presented to a NH (or near-NH) contralateral ear results in enhanced music enjoyment with respect to the acoustic signal alone. Remarkably, this two-ear enhancement experienced by CI-SSD listeners represents a substantial fraction of the two-ear enhancement seen in NH listeners. This unexpected benefit of electroacoustic auditory stimulation will have to be considered in theoretical accounts of music enjoyment and may facilitate the quest to enhance music enjoyment in CI users.

Electrically Nonconductive Occludent For Tissue Openings

Abstract: An electrically nonconductive occludent constructed and arranged to forcefully infill a tissue opening so as to effectively prevent transport of electrical current, fluid and bacteria through the tissue opening. A cochlear implant comprising: an elongate electrode carrier member having at least one electrode disposed thereon, wherein the carrier member is configured to traverse a cochleostomy to position the electrodes in the cochlea; and an electrically nonconductive occludent constructed and arranged to circumferentially surround a portion of the carrier member traversing the cochleostomy, and to forcefully infill cochleostomy thereby segregating perilymphatic canals of the cochlea from extracochlear regions.

Speech audiometry and data logging in CI patients : Implications for adequate test levels.

Abstract: As part of postoperative cochlear implant (CI) diagnostics, speech comprehension tests are performed to monitor audiological outcome. In recent years, a trend toward improved suprathreshold speech intelligibility in quiet and an extension of intelligibility to softer sounds has been observed. Parallel to audiometric data, analysis of the patients’ acoustic environment can take place by means of data logging in modern CI systems. Which speech test levels reflect the individual listening environment in a relevant manner and how can these be reflected in a clinical audiometric setting? In a retrospective analysis, data logs of 263 adult CI patients were evaluated for sound level and the listening situation (quiet, speech in quiet, noise, speech in noise, music, and wind). Additionally, monosyllabic word comprehension in quiet was analyzed in experienced CI users at presentation levels of 40–80 dB. For the sound level in the acoustic environment of postlingually deafened adult CI users, data logging shows a maximum occurrence of speech signals in the range of 50–59 dB. This demonstrates the relevance of everyday speech comprehension at levels below 60 dB. Individual optimization of speech intelligibility with a CI speech processor should not be performed in the range of 65–70 dB only, but also at lower levels. Measurements at 50 dB currently seem to be a useful addition.