The Mandibular Cycle and Reversed-sonority Onset Clusters in Russian

The sonority principle is dramatically violated by some Russian onset clusters (e.g., [lba]) and not by others. Russian onset clusters therefore provide a good test of a phoneticallymotivated, alternative hypothesis to the sonority hierarchy; namely, the hypothesis that the primary constraint on the sequential organization of segments is the relatively independent close-open mandibular cycle. The jaw movement of 3 native Russian speakers was recorded during the production of simple CV syllables as well as during the production of syllables with standard onset clusters and those with reversed-sonority clusters. Measurements of jaw height during segment production and segment duration indicate that while reversed-sonority clusters may violate the sonority principle, they behave like more standard syllables and conform to the mandibular cycle.