a b s t r a c tWhat is the proper unit of analysis in the psycholinguistics of dialog? While classical approaches are largely based on models of individual linguistic processing, recent advances stress the social coordinative nature of dialog. In the influential interactive alignment model, dialogue is thus approached as the progressive entrainment of interlocutors' linguistic behaviors toward the alignment of situation models. Still, the driving mechanisms are attributed to individual cognition in the form of automatic structural priming. Challenging these ideas, we outline a dynamical framework for studying dialog based on the notion of interpersonal synergy. Crucial to this synergetic model is the emphasis on dialog as an emergent, self-organizing, interpersonal system capable of functional coordination. A consequence of this model is that linguistic processes cannot be reduced to the workings of individual cognitive systems but must be approached also at the interpersonal level. From the synergy model follows a number of new predictions: beyond simple synchrony, good dialog affords complementary dynamics, constrained by contextual sensitivity and functional specificity. We substantiate our arguments by reference to recent empirical studies supporting the idea of dialog as interpersonal synergy.

This study investigates interpersonal processes underlying dialog by comparing two approaches, interactive alignment and interpersonal synergy, and assesses how they predict collective performance in a joint task. While the interactive alignment approach highlights imitative patterns between interlocutors, the synergy approach points to structural organization at the level of the interaction-such as complementary patterns straddling speech turns and interlocutors. We develop a general, quantitative method to assess lexical, prosodic, and speech/pause patterns related to the two approaches and their impact on collective performance in a corpus of task-oriented conversations. The results show statistical presence of patterns relevant for both approaches. However, synergetic aspects of dialog provide the best statistical predictors of collective performance and adding aspects of the alignment approach does not improve the model. This suggests that structural organization at the level of the interaction plays a crucial role in task-oriented conversations, possibly constraining and integrating processes related to alignment.

Sharing a public language facilitates particularly efficient forms of joint perception and action by giving interlocutors refined tools for directing attention and aligning conceptual models and action. We hypothesized that interlocutors who flexibly align their linguistic practices and converge on a shared language will improve their cooperative performance on joint tasks. To test this prediction, we employed a novel experimental design, in which pairs of participants cooperated linguistically to solve a perceptual task. We found that dyad members generally showed a high propensity to adapt to each other's linguistic practices. However, although general linguistic alignment did not have a positive effect on performance, the alignment of particular task-relevant vocabularies strongly correlated with collective performance. In other words, the more dyad members selectively aligned linguistic tools fit for the task, the better they performed. Our work thus uncovers the interplay between social dynamics and sensitivity to task affordances in successful cooperation.

HighlightsWe tested whether a confidence heuristic could replace interaction in a collective perceptual decision-making task.For individuals of nearly equal reliability, the confidence heuristic is just as accurate as interaction.For individuals with different reliabilities, the confidence heuristic is less accurate than interaction.Interacting individuals use the credibility of each other’s confidence estimates to guide their joint decisions.Interacting individuals face a problem of how to map ‘internal’ variables onto ‘external’ (shareable) variables.

What is the role of language in social interaction? What does language bring to social encounters? We argue that language can be conceived of as a tool for interacting minds, enabling especially effective and flexible forms of social coordination, perspective-taking and joint action. In a review of evidence from a broad range of disciplines, we pursue elaborations of the language-as-a-tool metaphor, exploring four ways in which language is employed in facilitation of social interaction. We argue that language dramatically extends the possibility-space for interaction, facilitates the profiling and navigation of joint attentional scenes, enables the sharing of situation models and action plans, and mediates the cultural shaping of interacting minds.