Prominence lent by rising and falling pitch movements: Testing two models.

Two experiments are reported in which a pitch-level difference (PLD) model for prominence perception [Hermes and Rump, J. Acoust. Soc. Am. 96, 83-92 (1994)] is subjected to further tests. The model holds that the contribution of pitch to the perceived degree of prominence is proportional to the difference in pitch level between the vocalic nuclei of the accented and the previous syllable. In experiment I, the influence of stretching and compressing the utterance in time was assessed. It was found that the predictions made by the model were not fully supported by the data. An alternative model was developed according to which pitch movements resynthesized in the same register lend equal prominence when pitch levels on the upper declination lines in the stimuli are equal. These two models gave different predictions when the lower declination lines are different. This was tested in experiment II. The results which are more or less between the predictions by the two models suggest that low pitch levels play a smaller role in prominence perception than high pitch levels do.