Tonal effects on perceived vowel duration

Cross-linguistically, there is a tendency for vowel duration to be inversely related to the approximate average f0; all else being equal, vowels on low tones are longer than those on high tones, while vowels on rising tones are longer than those on falling tones. This type of interplay between tonal contrasts and duration are commonly reflected in the world’s languages. This paper reports a study investigating the role of perception in the effect of tone on duration. Both f0 slope and height are found to exert an influence on perceived duration. Syllables with dynamic f0 are generally perceived as longer than syllables with flat f0. Syllables with higher f0 are heard as longer than syllables with lower f0. It is argued that the mismatch in the effects of f0 height on perceived duration and acoustic duration is due to hypercorrection. Perceived duration equality is achieved by acoustic duration adjustment. While this type of duration compensation might be characteristic of level tone perception, no such effect is apparent in the case of dynamic tone realization. Regardless of perceived or acoustic duration, contour tone syllables are generally longer than flat tone syllables. The difference between the effects of dynamic and flat f0 patterns on perceived and acoustic durations suggests that the perceptual mechanism for dynamic f0 is different from that of level f0.