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PubMed · 12851550

Dynamic range enhancement for cochlear implants.

Robert S Hong·Jay T Rubinstein·Dan Wehner·David Horn
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Abstract

HYPOTHESIS: The addition of a continuous, unmodulated, high-rate pulse train to sinusoidal stimuli presented by the cochlear implant to implant recipients will result in increases in the psychophysical dynamic range. BACKGROUND: The hearing dynamic range of cochlear implant patients is markedly reduced compared with that of normal-hearing individuals. This has negative implications for both speech perception and sound quality in these patients. It has been suggested that the addition of an unmodulated high-rate pulse train to deafened auditory nerves could create spontaneous-like neural activity, similar to that recorded from normal ears, of which one significant benefit would be an increase in the dynamic range of cochlear implant users. METHODS: Twenty-nine patients who underwent implantation with the Clarion CII device participated in this single-blinded prospective study. The psychophysical dynamic range of 28 of these subjects was measured with sinusoidal stimuli in response to various levels of an additional unmodulated high-rate pulse train. RESULTS: All the tested subjects (n = 28) demonstrated an increase in dynamic range in response to an appropriate level of unmodulated high-rate pulse train. The largest increase in dynamic range for each subject had a mean value of 6.7 dB. CONCLUSION: The addition of an unmodulated high-rate pulse train to the electric signal presented to cochlear implant patients results in significant increases in dynamic range for sinusoidal stimuli.

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Acoustic StimulationAdultAgedAuditory ThresholdCochlear ImplantsElectric Stimulation TherapyHearingHumansMiddle AgedProspective StudiesPsychophysicsSingle-Blind MethodTreatment OutcomeJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Robert S Hong, Jay T Rubinstein, Dan Wehner, David Horn. 2003. Dynamic range enhancement for cochlear implants.. https://doi.org/10.1097/00129492-200307000-00010

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