Tone-intonation interaction in context in Thai

Abstract

The acoustic realization of lexical tone is influenced by sentence-level intonation. For example, F0 measurements show that a phonologically falling tone in Thai is warped when overlaid with a falling intonational contour, causing F0 to fall further and to begin its decline at an earlier timepoint than when influenced by other contours. This categorical perception study, which includes both identification and discrimination tasks, uses a nine-step continuum of target words created with naturally produced lexical tone endpoints, presented within two different naturally produced sentence frames. Specifically, these tasks investigate the perception of high and falling tones in sentence-medial and sentence-final positions in Thai. This test of stimulus continua within natural sentence contexts reveals the listeners’ context-mediated perception of deviation from a canonical lexical tone, shedding light on the interaction and relative weights of both tone and intonation perception in natural speech, and also offering insight into the mechanism with which language users process suprasegmental information.