Effects of Frequency Allocation with an Extended Low Frequency Range on Syllable-initial Consonant Identification by Mandarin-speaking Pediatric Cochlear Implant Users

Abstract

BACKGROUND: To determine the effects of frequency allocation with an extended low-frequency range on consonant identification by Mandarin-speaking pediatric CI recipients. METHODS: Fifteen prelingually deafened, pediatric CI recipients participated in this study. Each patient's accuracy in consonant identification was compared in two conditions: (i) The experimental condition, where participants were mapped with an extended frequency range from 233 to 8,501 Hz, and (ii) the control condition, where participants were mapped with their clinically assigned frequency range from 300 to 8,404 Hz. RESULTS: The group mean of pediatric CI users’ consonant identification accuracy was 81.94% (SD=10.29%) in the experimental condition, and was 77.11% (SD=12.14%) in the control condition. The group mean was 4.83% (SD=6.29%) higher in the experimental condition than that in the control condition; this difference was statistically significant (t(14)=2.98, p=0.010). CONCLUSIONS: The present findings indicated that frequency allocation with extended frequency ranges under quiet situation does not introduce adverse effects on the same group of CI users' performance in recognizing contrasts in Mandarin syllable-initial consonants. Together, these findings suggest the potential clinical usefulness of frequency allocation with extended low-frequency range in pediatric CI users' recognition of Mandarin consonants.