Symmetry and Asymmetry in the Syntax-Phonology Interface * Hisao Tokizaki Sapporo University ABSTRACT. This paper argues that syntactic brackets are interpreted as prosodic boundaries, which block phonological changes such as Rendaku (sequential voicing) in Japanese, and Lateralization and n-Insertion in Korean. It is pointed out that there are symmetry and asymmetry between left-branching and right-branching structure with respect to their blocking effect. The symmetry of left/right-branching is explained by the mapping theory developed in Tokizaki (1999, 2006). It is argued that the asymmetry of left/right-branching is due to the fact that junctures between words are shorter in left-branching structure than in right-branching structure. This analysis has interesting consequences for possible patterns in phonological changes, the asymmetric nature of syntax, and typological correlations between word orders and syllable structure. Keywords: linearization, pause, prosody, compound, branching 1. Introduction One of the tasks of phonology is to show how syntactic structure is linearized into a sequence of sounds and pauses. In this paper, I will argue that linearization is effected differently in left-branching and right-branching structures. It will be argued that the phonology of Japanese and Korean compounds shows that left-branching structure is linearized with shorter junctures than right-branching structure. In section 2, I will outline the mapping theory developed in Tokizaki (1999, 2006). Section 3 is a discussion of the blocking effect of prosodic boundaries, and this section aims to show the symmetry and asymmetry of left/right-branching structure. In section 4, I will argue that the left-right asymmetry is due to the difference in juncture between left-branching and right-branching structures. Section 5 shows some consequences of this analysis. Finally, I summarize and conclude my arguments in section 6. 2. Linearization of Hierarchical Structure with Silence I have argued that the hierarchical structure of syntax is mapped onto phonology with various lengths of pause between words. The mapping rule (Tokizaki (1999, 2006)) is formulated as in (1). (1) Interpret boundaries of syntactic constituents [ ... ] as prosodic boundaries / ... /. For example, the rule (1) applies to the following sentence (2) to give its phonological representation (3). (2) [[Alice] [[loves] [hamsters]]] (3) // Alice /// loves // hamsters /// A prosodic boundary is interpreted as a silence of a certain length, which can be represented