Acoustic predictors of intelligibility for segmentally interrupted speech: Temporal envelope, voicing, and duration

Purpose: Temporal interruption limits the perception of speech to isolated temporal glimpses. An analysis was conducted to determine the acoustic parameter that best predicts speech recognition from temporal fragments that preserve different types of speech information-namely, consonants and vowels. Method: Young listeners with normal hearing previously completed word and sentence recognition tasks that required them to repeat word and sentence material that was temporally interrupted. Interruptions were designed to replace various portions of consonants or vowels with low-level noise. Acoustic analysis of preserved consonant and vowel segments was conducted to investigate the role of the preserved temporal envelope, voicing, and speech duration in predicting performance. Results: Results demonstrate that the temporal envelope, predominantly from vowels, is most important for sentence recognition and largely predicts results across consonant and vowel conditions. In contrast, for isolated words the proportion of speech preserved was the best predictor of performance regardless of whether glimpses were from consonants or vowels. Conclusion: These findings suggest consideration of the vowel temporal envelope in speech transmission and amplification technologies for improving the intelligibility of temporally interrupted sentences.