Relational Timing in the Production and Perception of Japanese Singleton and Geminate Stops

This work examines the production and perception of the Japanese singleton versus geminate stop contrast in order to investigate properties that distinguish the contrast in the face of variability due to speech rate. The acoustic study found two local relational durations, the ratio of the stop to the preceding mora and the ratio of the stop to the following vowel, to be stable across speaking rates and to accurately classify singleton and geminate productions. However, the subsequent perception study demonstrated an influential role of the preceding mora duration and a marginal role of the following vowel duration on listeners' categorization. These results demonstrate that Japanese listeners can take advantage of relative duration in the perception of the stop length contrast, and that relative strength of simultaneously available acoustic cues does not necessarily translate into equal perceptual importance.