1998 Volume 41 Issue 4 Pages 287-295
Objective: The main objective of this study was to evaluate differences in performance associated with changing assignment of frequency bands to electrodes of cochlear implant.
Design: Seven subjects with cochlear implant identified recorded vowels, consonant and sentences with changing seven frequency allocations. Evaluation was conducted immediately after changing frequency allocation.
Results: 1) Assignment to the upper frequency bands between 4500 and 6700Hz was found to be most suitable for speech identification. 2) Assignments to frequencies above 9000Hz was not effective for improvements. 3) Consonant's performance was not enhanced with any frequency boundaries.
Conclusions: 1) Considering of features in cochlear implants, the range of frequency allocation should not be applied to assign for speech frequency range. 2) It would be more effective for programing to decrease frequency bands above 6700Hz and to narrow frequency range of assignments to an electrode. 3) Increase of stimulus speed would make more improvement of consonant performance.