Phonetic Restoration of Temporally Reversed Speech

Early study showed that temporally reversed speech may still be very intelligible. The present work further assessed the role of acoustic cues accounting for the intelligibility of temporally reversed speech. Mandarin sentences were edited to be temporally reversed. Experiment 1 preserved the original consonant segments, and experiment 2 only preserved the temporally reversed fine-structure waveform. Experimental results with normal-hearing listeners showed that for Mandarin speech, listeners could still perfectly understand the temporally reversed speech with a reversion duration up to 50 ms. Preserving original consonant segments did not significantly improve the intelligibility of the temporally reversed speech, suggesting that the reversion processing applied to vowels largely affected the intelligibility of temporally reversed speech. When the local short-time envelope waveform was removed, listeners could still understand stimuli with primarily temporally reversed finestructure waveform, suggesting the perceptual role of temporally reversed fine-structure to the intelligibility of temporally reversed speech.