Real-World Performance of Directional Microphone Hearing Aids

ABSTRACTS

This article summarizes several recent studies of directional microphone hearing aid performance in everyday living conducted at Walter Reed Army Medical Center. It is clear that the directional benefit typically observed in controlled clinical testing often is not realized in ordinary listening situations. This is due, at least in part, to a variety of acoustic factors frequently encountered in everyday listening environments that disrupt the effectiveness of the directional processing. As a result, patients will not detect a significant performance difference between omnidirectional and directional processing in many everyday listening situations and, as a further result, some patients fit with switchable omnidirectional/directional hearing aids will eventually opt not to use the directional mode. Nevertheless, directional microphones can provide a significant benefit to patients under certain environmental conditions and most patients learn to identify ordinary listening situations where directional processing is distinctly preferred to omnidirectional processing. This is most likely to occur when background noise is present and the signal of interest is in front of and relatively near to the listener.

KEYWORDS

Hearing aid - omnidirectional microphone - directional microphone - everyday living - microphone preference

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