Effects of coda consonant on syllable-initial Voice Onset Time (VOT) in English and French: The Syllable-Body Stiffness Hypothesis.

The aspiration of syllable-onset voiceless stops in English, indexed as positive Voice Onset Time (VOT), is shorter before a voiceless consonant in the syllable coda than before a voiced one. Vowel duration is also known to be shorter before voiceless codas. We propose a unitary framework in which both patterns emerge from a cohesive change in onset and vowel articulatory stiffness modulated by coda constriction. In Experiment 1, onset VOT was measured from acoustic signals in American English monosyllabic words with a mildly constricted coda (/ɹ/) vs. a highly constricted coda (voiceless stop), as in par vs. pat. In Experiment 2, the effect was investigated for the first time in French mono- and disyllables containing the rhotic /ʁ/ vs. a voiceless stop, as in part /paʁ/ vs. patte /pat/ and patrie /patʁi/ vs. pâté /pate/. VOT in English was significantly longer before coda /ɹ/ than coda voiceless stop. In contrast, no significant effect was observed in French, the French rhotic patterning as a voiceless obstruent. Our English results suggest that voiceless obstruents, which have higher stiffness than voiced ones, are anticipated with a stiffness increase beginning in the onset, making stiffness an important aspect of the syllable's role in motor control. We propose the Syllable-Body Stiffness Hypothesis to account for both the VOT and vowel duration differences: Stiffness increases in the syllable body (onset and vowel together) to anticipate the intraoral pressure buildup and articulatory force of voiceless codas, producing faster articulations and shorter acoustic durations, including shorter onset aspiration.