The Mora or the Segment? Investigating the basic unit of spoken language processing through SOT data in Japanese

Language-specific rhythmic categories play a vital role in the processing of spoken language, which involves both speech perception and speech production. A number of researchers who have conducted perception and metalinguistic experiments argue that in Japanese the MORA is the basic rhythmic or timing unit of spoken language processing. However, the evidence from production experiments is less clear, leading some researchers to question the significance of mora-oriented phenomena in speech production (Terao 1992, Morais, Kolinsky, and Nakamura 1996). Thus it may be too much of an overgeneralization to apply the findings from perception and metalinguistic studies to production studies, i.e. to expect the mora to also be the most prominent unit in production. In previous psycholinguistic research, mora-oriented phenomena in Japanese speech processing have been investigated through the analysis of speech errors, stuttering, various segmentation and blend experiments, and perception experiments. Recently, Cutler and Otake (2002) showed that nonmoraic units such as segments are als