Prosodic strengthening in reference to the lexical pitch accent system in South Kyungsang Korean

Abstract

Theories of the phonetics-prosody interface suggest that prosodic strengthening that arises with prosodic structuring is not simply a low-level phonetic phenomenon, but it serves as a phonetic hallmark of a higher-order prosodic structure in reference to linguistic (phonological) contrast. The present study builds on this theoretical premise by examining acoustic realization of the phonological tonal contrast in the lexical pitch accent system of South Kyungsang (SK) Korean. Results showed that phonetic realization of F0 and the degree of glottalization (as reflected in spectral tilt measures such as H1-A1c and H1-A3c) of vowels in vowel-initial words were systematically modulated by the higher-order prosodic structure, and that the prosodic-structural modulation gave rise to distinct prosodic strengthening effects as a function of the source of prosodic strengthening. In particular, the prominence-induced strengthening (due to focus) entailed a phonetic polarizing effect on the F0 contrast in a way that enhances the phonological High vs. Low tone contrast. The boundary-induced strengthening effect, on the other hand, could be better understood as enhancing the phonetic clarity of prosodic junctures. The distinct prosodic strengthening effects were further evident in the way that glottalization was fine-tuned according to prosodic structure and phonological (tonal) contrast. Prosodic strengthening effects were also found to interact with intrinsic vowel height, implying that the low-level phonetic effect may be under speaker control in reference to higher-order prosodic and phonological contrast systems of the language. Finally, the results informed a theoretical debate regarding whether the Low tone that contrasts with the High tone in word-initial position should be considered lexically specified vs. post-lexical assigned.