Tone discrimination and speech perception benefit in Mandarin-speaking children fit with HiRes fidelity 120 sound processing

OBJECTIVE: To compare tone discrimination, speech perception, and general listening benefit in Mandarin-speaking children using standard HiRes and after 1, 3, and 6 months of HiRes 120 use. The HiResolution Bionic Ear is an implantable prosthesis designed to provide access to sound and to improve perception of speech via electrical stimulation of the auditory nerve. The newest sound-processing strategy is HiRes with Fidelity 120 (HiRes 120). In HiRes 120, the input signal is analyzed in greater spectral detail than with original HiRes to achieve a maximum of 120 spectral bands. HiRes 120 is expected to provide more benefit than the original HiRes because of the increased spectral resolution. SETTING: Cochlear implant/tertiary referral center. SUBJECTS: Seven children, aged 5 to 12 years, who had been implanted with a CII or 90K implant with a fully inserted electrode array and at least 10 contiguous programmable electrodes. DESIGNL: Tone discrimination, consonant identification, the Mandarin lexical neighborhood test (M-LNT), and the speech perception in noise (SPIN) tests were administered in 4 sessions: at a baseline visit with standard HiRes before being fit with HiRes 120 and at 1, 3, and 6 months after using HiRes 120. Each subject and his or her parents also completed a strategy preference questionnaire after using HiRes 120 for 6 months. RESULTS: Statistically significant improvements from baseline with HiRes to 6 months with HiRes 120 were found for tone discrimination (61.4 to 73.2%, p = 0.006) and for SPIN low predictability (65.7 to 74.7%, p = 0.039). Mean score changes of 47.4 to 50.4% (p = 0.499) for consonant perception, 82.9 to 86.4% for M-LNT (easy words; p = 0.322), 77.1 to 81.0% for M-LNT (hard words; p = 0.423), and 72.3 to 78.5% for SPIN high predictability (p = 0.427) showed trends for improvement but were not statistically significant. Questionnaire results indicated that all children and parents preferred HiRes 120 to HiRes. Strength of preference was 8.9 for children and 8.1 for parents on a scale of 1 to 10 (1 = weak preference, 10 = strong preference). CONCLUSION: Taken together, the improved tone discrimination and speech perception results, along with subjective improvements in speech fluency, discrimination, and music appreciation, indicate a trend toward superior listening benefit with HiRes 120 compared with standard HiRes in Mandarin-speaking children.