The iambic/trochaic law and bidirectional tone sandhi in Teochew languages

Abstract

This dissertation focuses on explaining the rhythmic structure of complex tone languages. The Iambic/Trochaic Law provides an extralinguistic motivation for asymmetrical foot inventories to explain the rhythm of stress languages under Metrical Stress Theory. According to the Iambic/Trochaic Law, there is a perceptual universal whereby intensity contrast leads to prominence-initial grouping and duration contrast leads to prominence-final grouping. However, how the Iambic/Trochaic Law applies to languages typically considered as tonal is mostly unknown. This dissertation sets out to apply the Iambic/Trochaic Law to complex tone languages with tone sandhi behaviours suspected to be under the influence of stress. In particular, the distinction between left and right tonal prominence displayed in bidirectional tone sandhi correlates with a metrical distinction between iambic and trochaic rhythm.

Four Teochew languages (Southern Min), namely Jieyang, Swatow, Chaozhou, and Chaoyang, are adopted to serve as a platform for acoustic measurements over the course of a minimal prosodic domain of two syllables showing six-way tone contrasts in sonorant-final syllables and bidirectional tone sandhi. Estimated values of duration and intensity generated from Linear Mixed-Effect Regression Models are used to indicate metrical prominence based on predictions of the Iambic/Trochaic Law. The results provide novel support for the Law.

Overall, results show that metrical prominence aligns with tonal prominence. There are duration and intensity asymmetries, sandhi syllables being less metrically prominent than citation syllables, citation syllables of one sandhi type adopting either duration or intensity to indicate metrical prominence over citation syllables of the other sandhi type depending on the sandhi type they belong to, and sandhi syllables of one sandhi type adopting either duration or intensity to indicate being metrically less prominent over sandhi syllables of the other sandhi type depending on the sandhi type they belong to. Stress, and hence foot structure, is relevant for determining rhythm in addition to pitch. Thus, metrical prominence in tone languages covers not only pitch, but also duration and intensity to form a whole package. Each Teochew dialect is shown to have its own characteristics, varying in how stringently the metrical hypothesis is obeyed, contributing to a distinctive accent in terms of rhythm for each dialect. The explanatory framework developed in this dissertation is expected to apply to the study of rhythmic structure of other tone languages.