Pitch duration as a cue for declination

Abstract

An utterance of a language often demonstrates the effect of declination, usually understood broadly as a reduction in certain physical or acoustic signals. Previous research on declination focuses primarily on the acoustic measures of pitch (such as the movement of pitch or the alternation of pitch span) or intensity. Neglected in the matter is the third acoustic dimension of speech duration. This paper reports on an experiment on declination focusing on pitch duration. The language studied is Mandarin Chinese. Six native Mandarin speakers are recruited. A total of 864 utterances of 2-to-9 syllables in four tones and four functional intonations are recorded and analyzed on Praat. The results show that the declination of pitch duration goes side by side along the pitch declination, both of which share the same physiological basis. Specifically, (1) the average pitch duration within the prosodic unit decreases gradually from the sentence-initial prosodic unit to the sentence-final one, (2) the pitch duration of the left-most syllable of the prosodic unit decreases gradually from the sentence-initial prosodic unit to the sentence-final one, and (3) the pitch duration of the right-most syllable of the prosodic unit decreases slightly from the sentence-initial prosodic unit to the sentence-final one.