Does pre-planning explain why predictability affects reference production?

How does thematic role predictability affect reference production? This study tests a planning facilitation hypothesis – that the predictability effect on reference form can be explained in terms of the time course of utterance planning. In a discourse production task, participants viewed two sequential event pictures, listened to a description of the first picture (depicting a transfer event between two characters), and then provided a description of the second picture (continuing with one thematic role character, either goal or source). We replicated previous findings that goal continuations lead to more reduced forms of reference and shorter latency to begin speaking than source continuations. Additionally, we tracked speakers’ eye movements in two periods of utterance planning, early vs. late. We found that 1) early pre-planning supports the use of reduced forms but is not affected by thematic role; 2) thematic role only affects late planning; and 3) in contrast with our hypothesis, planning does not account for predictability effects on reduced forms. We then speculate that discourse connectedness drives the thematic role predictability effect on reference form choice

Thematic role predictability and planning affect word duration

It is known that acoustic variation is influenced by the predictability of words and the information that they represent. What is unknown is whether acoustic reduction is also influenced by the referential predictability of thematic roles. We tested this question in two production experiments, where speakers heard a sentence with goal/source arguments, e.g., “Lady Mannerly [source] gave a painting to Sir Barnes [goal],” and described a picture of a subsequent action, e.g., “Sir Barnes threw it in the closet.” We analyzed the duration of full NP descriptions used to refer to the pictured character. We found that duration was shorter for references to the goal than the source, but only in Experiment 2, where the timing of the stimuli encouraged the participant to plan their response incrementally, and not Experiment 1, where participants could pre-plan their responses. The strongest finding across both experiments was that response latency predicted duration, and latency was influenced by the predictability of thematic roles: Goal continuations had significantly shorter latencies. Together, these findings suggest that thematic role predictability does affect acoustic duration, and may be related to the time needed for utterance planning