Acoustic correlates of articulatory prosodic strengthening in Korean

Abstract

Recent articulatory studies [e.g., Keating, Cho, Fougeron, and Hsu (1998), forthcoming] using electropalatography have shown that consonants are generally produced with greater linguopalatal contact in domain-initial positions. This effect, known as articulatory prosodic strengthening, is generally cumulative: the higher the prosodic position, the more linguopalatal contact. The goal of this paper is to test for acoustic correlates of any such articulatory variations in Korean consonants /n,t,th,t*/ in prosodic positions (Utterance-, IP-, AP-, Word- and Syllable-initial), so that eventually the perceptual significance of such correlates can be tested. Results show that the higher domain-initial positions are associated with longer VOTs; longer ‘‘total’’ voiceless duration in closure; lower rms burst energy in stops but with substantial inter-speaker/consonantal variations; lower % of voicing during closure; and lower acoustic energy for nasal /n/. In addition, vowels in domain-initial CV were not found to be necessarily longer in a higher position whereas vowels in domain-final positions were. Linear correlations between each of the acoustic parameters and the articulatory magnitude (linguopalatal contact) will also be discussed. All in all, this study shows that articulatory strengthening in Korean does produce reliable acoustic correlates, which mark off prosodic positions in the speech signal. [Work supported by NSF.]