Directional Microphone Hearing Aids in School Environments: Working Toward Optimization.

PURPOSE

The hearing aid microphone setting (omnidirectional or directional) can be selected manually or automatically. This study examined the percentage of time the microphone setting selected using each method was judged to provide the best signal-to-noise ratio (SNR) for the talkers of interest in school environments.

METHOD

A total of 26 children (aged 6-17 years) with hearing loss were fitted with study hearing aids and evaluated during 2 typical school days. Time-stamped hearing aid settings were compared with observer judgments of the microphone setting that provided the best SNR on the basis of the specific listening environment.

RESULTS

Despite training for appropriate use, school-age children were unlikely to consistently manually switch to the microphone setting that optimized SNR. Furthermore, there was only fair agreement between the observer judgments and the hearing aid setting chosen by the automatic switching algorithm. Factors contributing to disagreement included the hearing aid algorithm choosing the directional setting when the talker was not in front of the listener or when noise arrived only from the front quadrant and choosing the omnidirectional setting when the noise level was low.

CONCLUSION

Consideration of listener preferences, talker position, sound level, and other factors in the classroom may be necessary to optimize microphone settings.