Embedded articulation: shifts in location influence speech production

During a conversation, the durations of spoken words decrease with repeated use, potentially reflecting increased accessibility of information encoded by the words. However, prior research has assessed this shortening only within single settings, despite the fact that conversations may continue across different locales. Importantly, movement through physical space has been shown to influence the accessibility of information encountered in prior events. This experiment assessed whether reductions in speech duration would be attenuated by changing settings. Participants completed a map route duplication task with a partner. Midway through the experiment, participants changed rooms, changed partners, changed both or changed neither. Over four trials, the durations of utterances for 10 key words were measured. As hypothesised, word duration showed a negative linear pattern among those not changing settings, but a cubic pattern for those changing rooms. Specifically, utterances showed a significant increase in duration immediately after shifting rooms. In contrast to the effect of the room manipulation, changing partners did not lessen reductions in word duration. These results highlight both the situated nature of dialogical speech and extend prior work on the cognitive outcomes associated with event boundaries.