Long-term effects of non-linear frequency compression for children with moderate hearing loss

Abstract

Abstract

Objective: To evaluate non-linear frequency compression (NLFC) as a means to improve speech recognition for children with moderate to moderately-severe hearing loss following a six-month acclimatization period. Design: Within subject design with repeated measures across test conditions. Study Sample: Fifteen children, ages 5 to 13 years, with moderate to moderately-severe high-frequency sensorineural hearing loss were fitted with Phonak Nios, micro-sized, BTE hearing aids and evaluated after two six-week intervals with and without NLFC and again after a six-month period of consecutive NLFC use. Results: Using repeated measures analyses, the six-month results were compared to data that was collected following six-week trials with and without NLFC hearing aids (). Improvements seen with NLFC in the initial study () were maintained or significantly increased in the present study. When compared to the six-week data, aided non-sense syllable speech recognition thresholds in quiet and speech recognition in noise were significantly better at the six-month interval. Conclusions: These results suggest that NLFC improves audibility for and recognition of high-frequency speech sounds for children with moderate to moderately-severe hearing loss. In many cases, improvements found with NLFC increased with a longer period of acclimatization to the technology.

Sumario

Objetivo: Evaluar la compresión no lineal de la frecuencia (NLFC) como un medio para mejorar el reconocimiento del lenguaje en niños con pérdidas auditivas moderadas a moderadamente severas, luego de un periodo de seis meses de aclimatación. Diseño: Es un diseño intra-sujeto con mediciones repetidas en todas las condiciones de la prueba Muestra del Estudio: Quince niños, edades de 5 a 13 años, con hipoacusia sensorineural moderada a moderadamente severa en altas frecuencias, fueron adaptados con auxiliares auditivos retroauriculares, de micro-tamaño, Phonak Nios, y evaluado luego de dos intervalos de seis semanas, con o sin NLFC y de nuevo, luego de un periodo de seis meses de uso consecutivo de NLFC. Resultados: Usando análisis de medidas repetidas, los resultados a seis meses se compararon con datos que fueron recogidos luego de periodos de seis semanas, con y sin auxiliares auditivos NLFC (Wolfe y col, en prensa). Las mejorías que se ven con NLFC en el estudio inicial (Wolfe y col, en prensa) se mantuvieron o fueron significativamente aumentadas en el presente estudio. Cuando se compararon con los datos de seis semanas, los umbrales no amplificados de reconocimiento del lenguaje para sílabas sin sentido en silencio y de reconocimiento del lenguaje en ruido, fueron significativamente mejores en el intervalo de seis meses. Conclusiones: Estos resultados sugieren que la NLFC mejora la audibilidad y el reconocimiento de sonidos lingüísticos de alta frecuencia para niños con hipoacusias moderadas a moderadamente severas. En muchos casos, la mejoría encontrada con NLFC aumentó con un periodo más largo de aclimatación a la tecnología.

Key Words::

• Nonlinear frequency compression
• Moderate hearing loss
• Hearing aids

Acknowledgements

This study was funded by a grant from Phonak AG. The authors would like to thank the subjects and their families who participated in this study. We would also like to thank the two anonymous reviewers who provided valuable feedback on an earlier version of this paper.

Declaration of interest: There were no conflicts of interest that influenced the development and execution of this study, the analysis of the data collected within the study, nor the development of this paper. Drs. Myriel Nyffeler and Michael Boretzki are employees of Phonak, the manufacturer that developed the hearing aids that were used in this study, but neither Myriel nor Michael possessed any role in the development and execution of this study, the analysis of the data collected within the study, nor the drafting of this paper. Their inclusion as authors on this paper is warranted by the fact that they provided advice regarding the use of the hearing aid technology and some assessment materials used within this study as well as with technical descriptions included in this paper.