Perspective use and perspective shift in spatial dialogue

Previous research has shown variability in spatial perspective and the occurrence of perspective shifts to be common in monologic descriptions of spatial relationships, and in route directions, in particular. Little is known, however, about preferences and the dynamics of use of route vs. survey perspectives as well as perspective shifts in dialogue. These were the issues we addressed in a study of dialogic interaction where one participant instructed the other on how to navigate a wheelchair avatar in a shared environment towards a goal. Although there was no clear preference for one of the two perspectives overall, dialogues tended to evolve from an early incremental, local, ego-based strategy towards a later more holistic, global, and environment-oriented strategy in utterance production. Perspective mixing was also observed for a number of reasons, including the relative difficulty of spatial situations and changes across them, navigation errors by the interlocutor, and verbal reactions by the interlocutor.