When dyads act in parallel, a sense of agency for the auditory consequences depends on the order of the actions.

The sense of agency (SA) is the perception of willfully causing something to happen. Wegner and Wheatley (1999) proposed three prerequisites for SA: temporal contiguity between an action and its effect, congruence between predicted and observed effects, and exclusivity (absence of competing causal explanations). We investigated how temporal contiguity, congruence, and the order of two human agents' actions influenced SA on a task where participants rated feelings of self-agency for producing a tone. SA decreased when tone onsets were delayed, supporting contiguity as important, but the order of the agents' actions (lead, follow, or simultaneous) also mattered. Relative contiguity was the main determinant of SA, as delayed tones were usually attributed to the most recent action. This was unaffected by contingencies between the two actors' actions (Experiment 2), showing that contiguity has a powerful influence on SA, even during joint action in the presence of other cues.