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Computer-based Multitaper Spectrogram Program for Electroencephalographic Data
Published on: November 13, 2019
Application of the envelope difference index to spectrally sparse speech
Pamela Souza1, Eric Hoover, Frederick Gallun
1Northwestern University, Evanston, IL, USA. p-souza@northwestern.edu
Journal of Speech, Language, and Hearing Research : JSLHR
|January 11, 2012
Summary
Amplitude compression in hearing aids can distort speech envelopes, impacting consonant recognition. Higher Envelope Difference Index (EDI) values significantly reduce speech perception, even when other auditory cues are present.
Area of Science:
- Audiology
- Speech Processing
- Hearing Aid Technology
Background:
- Amplitude compression is a key hearing aid strategy for audibility and comfort.
- It can alter speech envelope cues, potentially affecting speech recognition.
- The Envelope Difference Index (EDI) previously showed moderate links to consonant recognition.
Purpose of the Study:
- To investigate the relationship between the Envelope Difference Index (EDI) and the recognition of spectrally sparse consonants.
- To determine the impact of envelope distortion on speech perception under conditions with reduced spectral information.
Main Methods:
- Vowel-consonant-vowel tokens were processed to limit spectral cues.
- Compression parameters were adjusted to create a range of Envelope Difference Index (EDI) values.
- Speech recognition was assessed in 20 individuals with normal hearing.
Main Results:
- Increased Envelope Difference Index (EDI) values led to decreased overall speech recognition.
- Perception of consonant features was also diminished at higher EDI values.
- These effects persisted across different vocoding methods and with or without periodicity cues.
Conclusions:
- The study establishes limits for acceptable envelope distortion in hearing aid processing.
- Findings inform the impact of envelope distortions when other speech cues are available.
- Understanding these limits is crucial for optimizing hearing aid algorithms.
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