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07:14
A Method to Study Adaptation to Left-Right Reversed Audition
Published on: October 29, 2018
Distance and reverberation effects on directional benefit
Todd A Ricketts1, Benjamin W Y Hornsby
1Dan Maddox Hearing Aid Research Laboratory, Vanderbilt Bill Wilkerson Center, Nashville, Tennessee 37212, USA. todd.a.ricketts@vanderbilt.edu
Ear and Hearing
|December 10, 2003
Summary
Directional hearing aids offer benefits in noise, even at greater distances in reverberant environments. Speech Transmission Index (STI) accurately predicts hearing aid performance across various conditions.
Area of Science:
- Audiology and Hearing Science
- Acoustics and Signal Processing
Background:
- Understanding directional hearing aid (HA) benefits and limitations is crucial for managing patient expectations.
- Speaker-to-listener distance and reverberation significantly impact hearing aid performance in noise.
Purpose of the Study:
- To evaluate the impact of speaker-to-listener distance on directional hearing aid benefit in two reverberant environments.
- To compare Speech Transmission Index (STI) measures with sentence recognition to predict performance across conditions.
Main Methods:
- Fourteen adults with sensorineural hearing impairment participated.
- Sentence recognition was measured in directional and omnidirectional modes across varying distances (1.2m, 2.4m, 4.8m) and reverberation levels (RT60=0.3s, 0.9s).
- Speech Transmission Index (STI) was measured in all 12 listening conditions.
Main Results:
- Directional benefit decreased with increasing distance in moderate reverberation but remained present at the farthest distance.
- No significant decrease in directional benefit was observed with increasing distance in low reverberation.
- Speech recognition patterns aligned with STI measurements across different distances, reverberation, and microphone modes.
Conclusions:
- Directional hearing aids provide benefits in noise, even beyond critical distances in low to moderate reverberation.
- Reduced direct sound energy from nearby noise sources likely contributes to directional benefit.
- Aided STI values effectively predict average word recognition across varying listening conditions.
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