People often coordinate actions with others, requiring an adjustable amount of self–other integration between actor’s and co-actor’s actions. Previous research suggests that such self–other integration (indexed by the joint Simon effect) is enhanced by agent similarity of the co-actor (e.g., high in intentionality). In this study, we aimed to extend this line of research by testing whether experiencing agency over a co-actor’s actions (vicarious agency) and/or action prediction strengthens the joint Simon effect. For this purpose, we manipulated experienced agency by varying the experienced control over a co-actor’s actions (Experiment 1), and action prediction regarding the co-actor’s actions (Experiment 2). Vicarious agency could effectively be induced, but did not modulate the size of the joint Simon effect. The joint Simon effect was decreased when the co-actor’s actions were unpredictable (vs. predictable) during joint task performance. These findings suggest social agency can be induced and effectively measured in joint action. Action prediction can act as an effective agency cue modulating the amount of self–other integration in joint action.

人们经常与他人协调行动，需要行动者和合作者的行动之间有一定程度的自我-他人整合。先前的研究表明，这种自我与他人的整合（以联合西蒙效应为指标）可以通过合作者的代理人相似性（例如，高意向性）得到增强。在这项研究中，我们的目的是通过测试对共同演员的行为（替代代理）和/或行为预测的体验代理是否会加强联合西蒙效应来扩展这一研究方向。为此，我们通过改变对共同演员的行为的经验控制（实验1）和关于共同演员的行为的行动预测（实验2）来操纵经验代理。可以有效地诱导替代代理，但不能调节联合西蒙效应的大小。当共同执行者在联合任务执行期间的行为不可预测（相对于可预测）时，联合西蒙效应会降低。这些发现表明，可以在联合行动中诱导和有效衡量社会代理。行动预测可以作为一种有效的机构线索，调节联合行动中自我与他人整合的程度。