title: The effect of fluctuating maskers on speech understanding of high-performing cochlear implant users.
abstract: OBJECTIVE
  The present study evaluated whether the poorer baseline performance of cochlear implant (CI) users or the technical and/or physiological properties of CI stimulation are responsible for the absence of masking release.
  
  
  METHODS
  This study measured speech reception thresholds (SRTs) in continuous and modulated noise as a function of signal to noise ratio (SNR).
  
  
  METHODS
  A total of 24 subjects participated: 12 normal-hearing (NH) listeners and 12 subjects provided with recent MED-EL CI systems.
  
  
  RESULTS
  The mean SRT of CI users in continuous noise was -3.0 ± 1.5 dB SNR (mean ± SEM), while the normal-hearing group reached -5.9 ± 0.8 dB SNR. In modulated noise, the difference across groups increased considerably. For CI users, the mean SRT worsened to -1.4 ± 2.3 dB SNR, while it improved for normal-hearing listeners to -18.9 ± 3.8 dB SNR.
  
  
  CONCLUSIONS
  The detrimental effect of fluctuating maskers on SRTs in CI users shown by prior studies was confirmed by the current study. Concluding, the absence of masking release is mainly caused by the technical and/or physiological properties of CI stimulation, not just the poorer baseline performance of many CI users compared to normal-hearing subjects. Speech understanding in modulated noise was more robust in CI users who had a relatively large electrical dynamic range.
authors: a University of Applied Science , Offenburg , Germany .|b Department of Otorhinolaryngology of the Medical Center , University of Freiburg , Germany .|c Department of Otolaryngology (ENT) / Head & Neck Surgery , University Medical Center of the Ludwig Maximilians University Munich , München , Germany , and.|d Bio-Inspired Information Processing, Technical University of Munich , Department of Electrical and Computer Engineering and Institute of Medical Engineering , Garching , Germany.
authors: Stefan
authors: S
authors: Zirn
authors: c Department of Otolaryngology (ENT) / Head & Neck Surgery , University Medical Center of the Ludwig Maximilians University Munich , München , Germany , and.
authors: Daniel
authors: D
authors: Polterauer
authors: d Bio-Inspired Information Processing, Technical University of Munich , Department of Electrical and Computer Engineering and Institute of Medical Engineering , Garching , Germany.
authors: Stefanie
authors: S
authors: Keller
authors: d Bio-Inspired Information Processing, Technical University of Munich , Department of Electrical and Computer Engineering and Institute of Medical Engineering , Garching , Germany.
authors: Werner
authors: W
authors: Hemmert
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D016022:Case-Control Studies; D003054:Cochlear Implants / Q000523:psychology*; D012048:Correction of Hearing Impairment / Q000295:instrumentation; D003638:Deafness / Q000503:physiopathology* / Q000534:rehabilitation; D005260:Female; D006801:Humans; D008297:Male; D009622:Noise; D010470:Perceptual Masking; D059629:Signal-To-Noise Ratio; D013067:Speech Perception; D013069:Speech Reception Threshold Test
keywords: Cochlear implant; electrical dynamic range; fluctuating noise; speech understanding