Jaw Displacement and Metrical Structure in Japanese: The Effect of Pitch Accent, Foot Structure, and Phrasal Stress

要旨

Natural languages organize their utterances into smaller rhythmical units; i.e. the observation which is often referred to as “metrical organization”. The specific phonetic realizations of metrical organizations differ from one language to another. For example, English makes use of strong-weak rhythmic alternations by way of stress (e.g. Liberman and Prince 1977, Prince 1983 et seq.), whereas Japanese primarily makes use of pitch accent 1). The acoustic correlates of English stress include, for example, increased duration and larger intensity (e.g. Fry 1955, 1958, Plag et al. 2011), whereas Japanese pitch accent is primarily realized as changes in F0 (Beckman 1986, Poser 1984, Sugito 1998, Weitzman 1970). The phonology of cross-linguistic patterns of metrical organization is now well understood largely owing to the development of Metrical Phonology (e.g. Liberman and Prince 1977, Gordon 2011, Hayes 1995). How English stress is realized acoustically is also well understood (e.g. Fry 1955, 1958, Gordon 2011, 2014, Plag et al. 2011). Less well studied, however, are articulatory correlates of metrical structure in natural languages. Several recent works based on EMA (ElectroMagnetic Articulograph) show that jaw displacement may reflect metrical organization of utterances in English (Erickson et al. 2012, 2014a, b, Menezes and Erickson 2013, see also de Jong 1995, Kelso et al. 1985, Vatikiotis-Bateson and Kelso 1993): the magnitude of metrical prominence correlates well with the magnitude of jaw displacement. Building on this research program, this paper explores a yet even less studied area of research; that is, how Japanese metrical structure is reflected in jaw displacement patterns. We specifically investigate how three aspects of Japanese metrical features—pitch accent, foot structure, and phrasal stress—manifest themselves in jaw displacement patterns.

主題