Perspective-taking is a key component of social interactions. However, there is an ongoing controversy about whether, when and how instances of spontaneous visuospatial perspective-taking occur. The aim of this study was to investigate the underlying factors as well as boundary conditions that characterize the spontaneous adoption of another person's visuospatial perspective (VSP) during social interactions. We used a novel paradigm, in which a participant and a confederate performed a simple stimulus-response (SR) compatibility task sitting at a 90° angle to each other. In this set-up, participants would show a spatial compatibility effect only if they adopted the confederate's VSP. In a series of 5 experiments we found that participants reliably adopted the VSP of the confederate, as long as he was perceived as an intentionally acting agent. Our results therefore show that humans are able to spontaneously adopt the differing VSP of another agent and that there is a tight link between perspective-taking and performing actions together. The results suggest that spontaneous VSP-taking can effectively facilitate and speed up spatial alignment processes accruing from dynamic interactions in multiagent environments.

Recent studies have demonstrated people's propensity to adopt others' visuospatial perspectives (VSPs) in a shared physical context. The present study investigated whether spontaneous VSP taking occurs in mental space where another person's perspective matters for mental activities rather than physical actions. Participants sat at a 90° angle to a confederate and performed a semantic categorization task on written words. From the participants' point of view, words were always displayed vertically, while for the confederate, these words appeared either the right way up or upside down, depending on the confederate's sitting position. Participants took longer to categorize words that were upside down for the confederate, suggesting that they adopted the confederate's VSP without being prompted to do so. Importantly, the effect disappeared if the other's visual access was impeded by opaque goggles. This demonstrates that human adults show a spontaneous sensitivity to others' VSP in the context of mental activities, such as joint reading.

Accumulating evidence suggests that humans spontaneously adopt each other's visuospatial perspective (VSP), but many aspects about the underlying mechanisms remain unknown. The aim of this study was to investigate whether knowledge about another's visual access systematically modulates spontaneous VSP-taking. In a spatial compatibility task, a participant and a confederate sat at a 90°angle to each other, with visual stimuli being aligned vertically for the participants and horizontally for the confederate. In this task, VSP-taking is reflected in a spatial compatibility effect in the participant, because stimulus-response compatibility occurs only if the participant takes the confederate's perspective. We manipulated the visual access of the confederate during the task by means of glasses with adjustable shutters that allowed or prevented the confederate from seeing the visual stimuli. The results of 2 experiments showed that people only adopted their task partner's VSP if that person had unhindered visual access to the stimuli. Provided that the confederate had visual access to the participant's stimuli, VSP-taking occurred regardless of whether the confederate performed the same visual task as the participant (Experiment 1) or a different, auditory task (Experiment 2). The results suggest that knowledge about another's visual access is pivotal for triggering spontaneous VSP-taking, whereas having the same task is not. We discuss the possibility that spontaneous VSP-taking can effectively facilitate spatial alignment processes in social interaction. (PsycINFO Database Record