The influence of speech prosodic structure and syllable composition on consonant VOT in Japanese

This research elaborates the joint influences of the position relative to the accented prosodic component and syllable composition on the stops VOT in Japanese. Monosyllables and disyllables start with three types of plosives, namely bilabial, alveolar, and velar, are studied on different positions in prosodic sentences—pre-focus, on-focus, and post-focus. Results show that narrow and contrastive focus prolong the voiced on-focus stops (including bilabial, alveolar, and velar) which bear positive values in broad-focus sentences; but compress the on-focus voiceless consonants (including bilabial, alveolar, and velar) which have negative values neutrally. On the position of pre-focus, voiced consonants shorten the VOT towards to zero, especially for the velar voiced consonants; the voiceless ones follow this pattern exactly. On the position of post-focus, noticeably, the voiced and the voiceless plosives always show the opposite patterns—both of narrow and contrastive focus elicit a longer VOT on following voiced stops but reduce the VOT of voiceless consonants following them. The voiced alveolar show the most apparent compression at pre-focus, which always close to zero. Kinds of results describe significant interaction influences among different factors that bear the potential to change consonant VOT in Japanese.