Consistency of tone-syllable alignment across different syllable structures and speaking rates

Previous studies have reported that F0 contours of lexical tones in Mandarin are closely aligned with the syllables that carry them and that this alignment is late-adjusted so that the most appropriate F0 contour of a tone occurs mainly in the later portion of the host syllable. These studies, however, examined tone alignment only in syllables with a simple CV structure. The present study compared tone-syllable alignment patterns in syllables with a final nasal (the only final consonant allowed in Mandarin) to those without a final nasal at three speaking rates - normal, fast and slow. Experiment 1 found that regardless of internal syllable structure, the F0 contours for all of the four Mandarin tones maintain a consistent alignment to the syllables that carry them. Experiment 2 found that whether or not the syllable has a final nasal and regardless of speaking rate, the F0 peak associated with the R (rising) tone always occurs near the offset of the R-tone-carrying syllable, the onset of the F0 rise always occurs near the center of the syllable and the slope of the rise does not vary systematically with either syllable structure or speaking rate. These findings are interpreted as indicating that the syllable is the proper domain for tone implementation and that tone contours such as rising and falling are probably implemented as integral dynamic targets rather than as sequences of static targets.