Resistance to learning binaurally mismatched frequency-toplace maps: Implications for bilateral stimulation with cochlear implants

Catherine Siciliano, Catherine M. Siciliano, Andrew Faulkner, Stuart Rosen, Katharine Mair

    Research output: Contribution to journalArticlepeer-review

    Abstract

    Simulations of monaural cochlear implants in normal hearing listeners have shown that the deleterious effects of upward spectral shifting on speech perception can be overcome with training. This study simulates bilateral stimulation with a unilateral spectral shift to investigate whether listeners can adapt to upward-shifted speech information presented together with contralateral unshifted information. A six-channel, dichotic, interleaved sine-carrier vocoder simulated a binaurally mismatched frequency-to-place map. Odd channels were presented to one ear with an upward frequency shift equivalent to 6 mm on the basilar membrane, while even channels were presented to the contralateral ear unshifted. In Experiment 1, listeners were trained for 5.3 h with either the binaurally mismatched processor or with just the shifted monaural bands. In Experiment 2, the duration of training was 10 h, and the trained condition alternated between those of Experiment 1. While listeners showed learning in both experiments, intelligibility with the binaurally mismatched processor never exceeded, intelligibility with just the three unshifted bands, suggesting that listeners did not benefit from combining the mismatched maps, even though there was clear scope to do so. Frequency-place map alignment may thus be of importance when optimizing bilateral devices of the type studied here. © 2010 Acoustical Society of America.
    Original languageEnglish
    Pages (from-to)1645-1660
    Number of pages15
    JournalJournal of the Acoustical Society of America
    Volume127
    Issue number3
    DOIs
    Publication statusPublished - 2010

    Fingerprint

    Dive into the research topics of 'Resistance to learning binaurally mismatched frequency-toplace maps: Implications for bilateral stimulation with cochlear implants'. Together they form a unique fingerprint.

    Cite this