Full-array channel discrimination in cochlear implants: validation and clinical application

International Journal of Audiology, vol. 62, pp. 992–1001

Abstract

OBJECTIVE: We sought to validate our proposed tool for estimating channel discrimination of cochlear implant (CI) users along the full electrode array and to assess associations between place-pitch discrimination and speech perception. DESIGN: In two tests, participants identified one stimulus (probe) as the odd-one-out compared with two reference stimuli. Probe stimuli were evoked using dual electrode stimulation characterised by the current steering coefficient α. The first test measured psychometric functions (PFs) on pre-defined contacts, with just a noticeable difference (JNDα) as the outcome variable. The second test estimated channel discrimination on the full electrode array, yielding a discrimination score of Dα. We measured speech perception as free-field consonant-vowel-consonant phoneme recognition scores. STUDY SAMPLE: We included 25 adults with at least 6 months of CI experience. RESULTS: < 0.001). Mean JNDα and speech perception scores showed significant relationships in quiet and in noise. CONCLUSIONS: Dα correlated strongly with JNDα scores obtained with the PFs. For poor performers, the full-array test may underestimate JNDα. The full-array pitch discrimination test could be a helpful clinical tool, such as for fitting regions of lesser pitch discrimination ability.

Authors 5

1. Coen A. A. Windmeijer corresponding Aachen ENT-department

   Leiden University · Leiden University Medical Center

   Affiliation as printed

   ENT Department, Leiden University Medical Centre, Leiden, The Netherlands

2. Jan Dirk Biesheuvel Aachen ENT-department

   Leiden University · Leiden University Medical Center

   Affiliation as printed

   ENT Department, Leiden University Medical Centre, Leiden, The Netherlands

3. Peter-Paul B. M. Boermans Aachen ENT-department

   Leiden University · Leiden University Medical Center

   Affiliation as printed

   ENT Department, Leiden University Medical Centre, Leiden, The Netherlands

4. Jeroen Johannes Briaire Aachen ENT-department

   Leiden University · Leiden University Medical Center

   Affiliation as printed

   ENT Department, Leiden University Medical Centre, Leiden, The Netherlands

5. Johan H. M. Frijns Aachen ENT-department Leiden Institute for Brain and Cognition

   Leiden University · Leiden University Medical Center

   Affiliation as printed

   ENT Department, Leiden University Medical Centre, Leiden, The Netherlands

   Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands