OBJECTIVE: The full benefit of bilateral cochlear implants may depend on the unilateral performance with each device, the speech materials, processing ability of the user, and/or the listening environment. In this study, bilateral and unilateral speech performances were evaluated in terms of recognition of phonemes and sentences presented in quiet or in noise. DESIGN: Speech recognition was measured for unilateral left, unilateral right, and bilateral listening conditions; speech and noise were presented at 0° azimuth. The 'binaural benefit' was defined as the difference between bilateral performance and unilateral performance with the better ear. STUDY SAMPLE: Nine adults with bilateral cochlear implants participated. RESULTS: On average, results showed a greater binaural benefit in noise than in quiet for all speech tests. More importantly, the binaural benefit was greater when unilateral performance was similar across ears. As the difference in unilateral performance between ears increased, the binaural advantage decreased; this functional relationship was observed across the different speech materials and noise levels even though there was substantial intra- and inter-subject variability. CONCLUSIONS: The results indicate that subjects who show symmetry in speech recognition performance between implanted ears in general show a large binaural benefit.
OBJECTIVE: The full benefit of bilateral cochlear implants may depend on the unilateral performance with each device, the speech materials, processing ability of the user, and/or the listening environment. In this study, bilateral and unilateral speech performances were evaluated in terms of recognition of phonemes and sentences presented in quiet or in noise. DESIGN: Speech recognition was measured for unilateral left, unilateral right, and bilateral listening conditions; speech and noise were presented at 0° azimuth. The 'binaural benefit' was defined as the difference between bilateral performance and unilateral performance with the better ear. STUDY SAMPLE: Nine adults with bilateral cochlear implants participated. RESULTS: On average, results showed a greater binaural benefit in noise than in quiet for all speech tests. More importantly, the binaural benefit was greater when unilateral performance was similar across ears. As the difference in unilateral performance between ears increased, the binaural advantage decreased; this functional relationship was observed across the different speech materials and noise levels even though there was substantial intra- and inter-subject variability. CONCLUSIONS: The results indicate that subjects who show symmetry in speech recognition performance between implanted ears in general show a large binaural benefit.
Authors: Richard Ramsden; Paula Greenham; Martin O'Driscoll; Deborah Mawman; David Proops; Louise Craddock; Claire Fielden; John Graham; Leah Meerton; Carl Verschuur; Joseph Toner; Cecilia McAnallen; Jonathan Osborne; Maire Doran; Roger Gray; Margaret Pickerill Journal: Otol Neurotol Date: 2005-09 Impact factor: 2.311
Authors: Roland Laszig; Antje Aschendorff; Matthias Stecker; Joachim Müller-Deile; Steffen Maune; Norbert Dillier; Benno Weber; Matthias Hey; Klaus Begall; Thomas Lenarz; Rolf-D Battmer; Melanie Böhm; Thomas Steffens; Juergen Strutz; Thomas Linder; Rudolf Probst; John Allum; Martin Westhofen; Wolfgang Doering Journal: Otol Neurotol Date: 2004-11 Impact factor: 2.311