Abstract
During joint actions, individuals coordinate their movements in space and time to achieve common goals. It has been suggested that action co-representation, a process in which co-actors represent each other’s responses, facilitates joint action. One of the methods used to explore action co-representation, the Joint Simon (JS) task, has revealed that when pairs of individuals sit next to each other, participants’ response times to targets presented in front of them are shorter than response times to targets presented in front of their partner. The action co-representation account of this effect holds that it emerges due to facilitatory and inhibitory processes that occur as a consequence of the representation of a co-actor’s response. Guagnano et al. (2010), however, have argued against the action co-representation account, having observed that participants sitting in each other’s extrapersonal space did not exhibit a JS effect in a JS task modified to reduce its social nature. Based on this null result, Guagnano et al. suggested that typical JS effects emerge due to a heightened social context and the spatial proximity of participants. To test and expand this alternative account, we conducted a series of experiments designed to map the spatial coordinates of the JS effect. The only consistent findings in these experiments, however, were JS effects when co-actors performed the task in extrapersonal space. Due to the contrast between our results and those observed by Guagnano et al., we attempted to replicate the key null effect using Guagnano et al.’s adapted version of the JS task. We found a significant JS effect in the extrapersonal space condition. Considering these studies together, we suggest that Guagnano et al.’s null effect was an anomaly and reassert that action co-representation is the process underlying JS effects.
Meeting abstract presented at VSS 2012