Consonant perception by users of Nucleus and Clarion multichannel cochlear implants

A study was carried out to compare the consonant perceptions of five Nucleus multichannel cochlear implant users, five Clarion-CIS users, and four Clarion-CA users. All subjects were administered the Iowa Medical Consonant Recognition Test in the auditory-only condition. The groups averaged approximately 1 year of implant use at the time of testing, and the average age at implantation was 47 years for the Nucleus users, 60 years for the Clarion-CIS users, and 56 years for the Clarion-CA users. The percent-corrected scores for all three devices were variable and ranged from 34% to 84%, with each group averaging about 50% correct consonant recognition. Consonant feature information transmission was calculated for five features: manner of articulation, nasality, place of articulation, duration, and voicing. The highest information transmission in the Nucleus group was for the features of duration (71%), nasality (60%), and voicing (57%), which agrees with previous studies. The Clarion-CIS group had the highest information transmission for duration, place of articulation, manner of articulation, and nasality (50%, 29%, 28%, and 27%). The Clarion-CA group had the highest information transmission for the features voicing, place of articulation, and duration (41%, 40%, and 37%). This study indicates that the Clarion device may carry some acoustic information related to place of articulation, a feature that has not been found to be encoded well by other multichannel cochlear implants.