Maximum jaw displacement in contrastive emphasis

Maximum jaw displacement for a syllable (or word), measured as the lowest vertical jaw position relative to the maxillary occlusal plane using X-ray microbeam data was examined in the context of sets of utterances differing in terms of contrastive emphasis. It was found that there is a consistent and significant increase in jaw opening on the emphasized word for the three speakers examined. Moreover, the jaw opening on the other welds in the utterance is also affected by emphasis according to this preliminary study: The amount of jaw opening of the syllables following emphasis is reduced, and the amount of drop in jaw opening from the emphasized syllable to the following syllabic is increased