Difference in Speech Recognition between a Default and Programmed Telecoil Program

Area of Science:

• Audiology
• Speech-Language Pathology
• Hearing Aid Technology

Background:

• Hearing loss can lead to social isolation, with telephone use often hindered by technical limitations.
• Telecoils can improve signal clarity, but research on optimizing their frequency response is limited.
• Matching telecoil frequency response to microphone targets (like NAL-NL1) may enhance telephone communication for hearing aid users.

Purpose of the Study:

• To investigate if programming hearing aid telecoils improves speech recognition compared to default settings.
• To assess speech recognition differences between male and female talkers in different telecoil conditions.
• To evaluate speech recognition for sentences and monosyllabic words using programmed versus default telecoils.

Main Methods:

• A single-blinded randomized controlled trial involving 20 hearing aid users and 10 normal-hearing participants.
• Hearing aids were programmed to NAL-NL1 targets, with one telecoil set to default and another programmed to match microphone frequency response.
• Speech recognition was measured using AZ-BIO sentences and CNC words with both telecoil programs.

Main Results:

• The programmed telecoil condition showed significantly improved overall speech recognition compared to the default telecoil (p < 0.001).
• Speech recognition was significantly better with a male talker compared to a female talker (p < 0.001).
• Performance with sentences was superior to monosyllabic words and phonemes in both telecoil conditions (p < 0.001).

Conclusions:

• Programming hearing aid telecoils to match microphone frequency response significantly enhances speech recognition.
• This optimized telecoil setting benefits all tested speech stimuli (sentences, monosyllables, phonemes).
• Male talkers further improved speech recognition outcomes in both telecoil conditions.