title: Interaction between electric and acoustic cues in diotic condition for speech perception in quiet and noise by cochlear implantees.
abstract: OBJECTIVE
  This study aimed to evaluate the interaction of electric and acoustic cues in diotic condition in cochlear implantees.
  
  
  METHODS
  Five adult cochlear implantees with residual contralateral hearing were prospectively evaluated in hearing aid only (HA), cochlear implant only (CI), and HA + CI modes by audiometry (pure tone, dissyllabic words, and sentences), and sound quality questionnaires. CI electrodes corresponding to preserved frequencies in the contralateral ear (free-field aided thresholds, <50 dB) were then deactivated, and patients were retested after 20 to 30 days.
  
  
  RESULTS
  Sentences in silence showed a benefit of CI and the additive effect of HA + CI. As expected, performances with CI alone decreased after apical electrode deactivation. In contrast, speech performances (Marginal Benefit from Acoustic Amplification sentences) in HA + CI mode were not altered by electrode deactivation in silence (90 ± 5.9% before versus 81 ± 10.1% after deactivation, not significant, 2-way analysis of variance) or in noise (78 ± 4.8% before versus 66 ± 11.9% after deactivation, not significant, 2-way analysis of variance). Performances for dissyllabic words confirmed these results. Questionnaires showed a significant compensation of partial electrode deactivation by the contralateral hearing. Moreover, the human voice was reported to be significantly less metallic.
  
  
  CONCLUSIONS
  These results suggested a significant complementarity of acoustic and electric diotic cues but also some redundancy affecting the sound quality.
authors.affiliation: Otolaryngology Department, APHP, Hôpital Beaujon, Clichy, France.
authors.forename: Céline
authors.initials: C
authors.lastname: Richard
authors.forename: Evelyne
authors.initials: E
authors.lastname: Ferrary
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Borel
authors.forename: Olivier
authors.initials: O
authors.lastname: Sterkers
authors.forename: Alexis Bozorg
authors.initials: AB
authors.lastname: Grayeli
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D001301:Audiometry, Pure-Tone; D003054:Cochlear Implants; D018592:Cross-Over Studies; D003463:Cues; D003638:Deafness / Q000628:therapy; D004558:Electric Stimulation; D005260:Female; D006310:Hearing Aids; D006801:Humans; D008297:Male; D008875:Middle Aged; D009622:Noise / Q000009:adverse effects*; D011446:Prospective Studies; D012919:Social Behavior; D013060:Speech; D013067:Speech Perception / Q000502:physiology*; D011795:Surveys and Questionnaires; D055815:Young Adult