Timing of pitch movements and perceived vowel duration

Abstract

The hypothesis was tested that the timing of accent-lending pitch movements influences the perceived duration of a vowel. Dutch subjects were asked to adjust the physical duration of a vowel so as to fit into the temporal structure of a sentence. The vowel occurred in a monosyllabic word embedded in a carrier sentence. Three pitch movements on the vowel were used, a rise, a rise-fall, and a fall. Two opposite trends were found: the earlier the fall, the longer the duration of the target vowel was adjusted, the earlier the rise or rise-fall, the shorter its duration was adjusted. Control experiments indicated that the results should be interpreted in terms of a trade-off between the effects on prominence of timing of pitch movements and physical segment duration. It is concluded that late timing of pitch movements enhances the perceived vowel duration, but that this effect depends on the kind of pitch movement: the effect is cancelled in the case of late rises and rise-falls, whereas it is enhanced in the case of late falls by virtue of the enhancing effect on prominence of the accented syllable.