Improved Speech Recognition for Children With Limited Usable Hearing Unilaterally When Using a Remote Microphone in a...

Children with limited usable hearing unilaterally (LUHU) often struggle in noisy and reverberant classrooms. They cannot always be positioned near the teacher, and therefore, understanding the effect of distance on their understanding of speech is critical. This study assessed the performance of children using a remote microphone system in a simulated classroom environment located at varying distances from a teacher speaking from a frontal position.

Sixteen children with LUHU were fitted with a Phonak Roger Focus II ear-level receiver (Sonova AG) in the normal ear, coupled with the Phonak Roger Touchscreen Mic (Sonova AG). The children repeated AzBio sentences with and without the Roger Focus II in "quiet" and "noisy" (uncorrelated classroom noise) classroom environments, with speech at 65 dBA and noise at 55 dBA and speech at 72 dBA and noise at 65 dBA, respectively, at the various locations. A control group of 10 children with normal hearing (NH) was included.

A statistically and clinically significant (p < .004) improvement in speech recognition performance relative to unaided performance was observed with the Roger Focus II in all conditions, except the quiet classroom at 1.5 m, where the difference was statistically significant only. The largest gain (60%) was observed in the noisy classroom at 5 m (-2 dB SNR). Children using the remote microphone outperformed NH children under all conditions, and this was both clinically and statistically significant at all three distances in the noisy classroom (p < .004).

In children with LUHU, the Roger Focus II effectively reduced the impact of background noise and allowed for a greater distance between the teacher in front of the classroom and the listener in a simulated classroom setting. Children with LUHU demonstrated superior speech recognition abilities compared with those with NH in the most challenging conditions when seated farthest from the teacher. Future studies should examine subjective feedback in real-life classrooms across a wide variety of dynamic listening scenarios.