Phonetic implementation and the interpretation of downstepping in Mainstream US English

This study explores downstepping in Mainstream US English using three experiments. Experiment 1 investigated if downstep was associated with accessible referents. Pairs of scenarios were constructed: one with new information and one with accessible. Two versions of the target utterances were recorded (one with high star, and one with downstepping) and presented in the accessible and new contexts. The high star contour was preferred overall, but less so in accessible contexts. A statistical model showed an effect of the phonetic implementation of the contour. Experiment 2 examined the phonetic realizations of the utterances in Experiment 1 using a categorical perception discrimination task. Participants showed linear perception within the downstep contours but a categorical difference between the high star and downstep contours. Experiment 3 explored the interpretations attached to downstepping. Listeners showed a categorical difference between high star and downstep contours for interpretation, hearing downstep as indicating something had happened before, and more resigned, disappointed, and less clear than high star contours. There was also variation within the downstep contours based on phonetic implementation of the contour. We show that downstep contours have distinct meanings from high star contours, and that these meanings may be mediated by their phonetic implementation.