Perception of time-compressed rapid acoustic cues in French CV syllables

Abstract

The cognitive use of the phonetic and acoustic features still needs to be specified for speech comprehension. Several studies have established that children with language impairments like dyslexia exhibit deficits in perceiving rapid speech sounds. Our study explored the temporal encoding of acoustic cues during natural speech perception. We focused on two short attributes of speech: Voice Onset Time (VOT) and formant transitions. Bisyllabic CVCVs were constructed using stop consonants (/b/, /d/, /p/ and /t/) and vowels (/a/ and /i/). Normal hearing subjects had to identify the stimuli timecompressed acoustic cues simultaneously (Experiment 1) and separately on each cue (Experiments 2 and 3). Our results showed a non additivity of the acoustic cues and demonstrated that the VOT is a greater temporal cue than the formant transition. In addition, the redundancy of those ones is used to restore the degraded speech signal. However, both acoustic cues are needed to realize a fine perception of speech.