title: Differences between electrode-assigned frequencies and cochlear implant recipient pitch perception.
abstract: CONCLUSIONS
  This study demonstrated an evident mismatch between frequencies assigned to electrodes and frequencies evoked by stimulation of those same electrodes in implanted patients. We propose that the mapping procedures should include, whenever possible, a comparison with homolateral residual hearing in order to obtain an appropriate frequency range assignation for each electrode.
  
  
  OBJECTIVE
  The study aimed to investigate the correspondence between the frequencies assigned to each electrode and those actually perceived by the cochlear implant patient.
  
  
  METHODS
  We studied five post-lingually deaf adults with detectable residual hearing in the implanted and in the contralateral ear, who had each received a Cochlear implant. An ACE standard setting was used for mapping. The patients were asked to match the electric pitch with the acoustic one following presentation of pure tones to both the implanted and the contralateral ear.
  
  
  RESULTS
  In almost all patients the two most apical electrodes evoked higher frequencies than those assigned by the mapping software (E22 = 188-313, E21 = 313-438 Hz). Therefore, electric stimulation seems not to determine pitch sensations for frequencies <500 Hz. For most electrodes there is no correspondence between the acoustic pitch and the assigned frequency ranges. Moreover, these results were almost always different when stimulating the implanted and the contralateral ear.
authors: Institute of Otorhinolaryngology, Catholic University of the Sacred Heart, Rome, Italy.
authors: Walter Di
authors: WD
authors: Nardo
authors: Italo
authors: I
authors: Cantore
authors: Francesca
authors: F
authors: Cianfrone
authors: Pietro
authors: P
authors: Melillo
authors: Anna Rita
authors: AR
authors: Fetoni
authors: Gaetano
authors: G
authors: Paludetti
mesh_terms: D000328:Adult; D001301:Audiometry, Pure-Tone; D003054:Cochlear Implants; D003638:Deafness / Q000534:rehabilitation*; D004292:Dominance, Cerebral; D004567:Electrodes, Implanted; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010898:Pitch Perception; D012984:Software; D013018:Sound Spectrography