Boundary signaling in tonal and non-tonal dialects of Kammu

Kammu, a Mon-Khmer language spoken in Northern Laos is a language that has developed lexical tones rather recently, from the point of view of language history. One of the main dialects of this language is a tone language of the “East Asian” type with (high or low) tone on each syllable, while the other main dialect lacks lexical tones. The dialects differ only marginally in other respects. This type of language material allows us to investigate how the existence of lexical tones in a given language influences the use of intonation in that language, especially as a signal for focus and phrasing. We performed an introductory study of phrase intonation in tonal vs. non-tonal dialects of Kammu. As awaited we do find differences in boundary signaling. In both types of dialects the differentiation between (pragmatically) marked and unmarked boundaries is relevant. At marked phrase boundaries we find signaling of focus and of some expressive meanings. The difference between the two types of dialects is in the functional load of the intonational gestures. Thus in the tone dialects pragmatically marked boundaries are assigned high pitch, while in nontonal dialect it is a pitch fall that has a high pragmatic load.