Assessing the prosodic licensing of wh-in-situ in Japanese: A computational-experimental approach

The relationship between syntactic structure and prosodic structure has received increased theoretical attention in recent years. Richards (2010) proposes that Japanese allows wh-elements to stay in situ because of a certain aspect of its prosodic system. Specifically, in contrast to some other languages like English, Japanese can prosodically group wh-elements together with their licensers. This prosodic grouping is phonetically signaled by eradication or reduction of the lexical pitch accents of intervening words. In this theory, a question still remains as to whether each syntactic derivation is checked against its phonetic realization, or what allows Japanese wh-elements to stay in situ is more abstract phonological prosodic structure, whose phonetic manifestations can potentially be variable. This paper reports an experiment which addressed this question, by testing whether there is eradication or reduction of lexical pitch accents based on the detailed analysis of F0 contours. Our analysis makes use of a computational toolkit that allows us to assess the presence of tonal targets on a token-by-token basis. The results demonstrate that almost all speakers produce some wh-sentences which show reduction or eradication of the lexical pitch accents, as well as some that do not. Those tokens that show reduction or eradication directly support the prediction of Richards’ (2010) theory. The variability observed in the results suggests that the property of Japanese that allows their wh-elements to stay in situ must be abstract, phonological prosodic structure, whose phonetic realizations can vary within and across speakers. We discuss several possible mechanisms through which such phonetic variation can arise.