Referential coding does not rely on location features: Evidence for a nonspatial joint Simon effect.

Abstract

The joint Simon effect (JSE) shows that the presence of another agent can change one's representation of one's task and/or action. According to the spatial response coding approach, this is because another person in one's peri-personal space automatically induces the spatial coding of one's own action, which in turn invites spatial stimulus-response priming. According to the referential coding approach, the presence of another person or event creates response conflict, which the actor is assumed to solve by emphasizing response features that discriminate between one's own response and that of the other. The 2 approaches often make the same predictions, but the spatial response coding approach considers spatial location as the only dimension that can drive response coding, whereas the referential coding approach allows for other dimensions as well. To compare these approaches, the authors ran 2 experiments to see whether a nonspatial JSE can be demonstrated. Participants responded to the geometrical shape of a central colored stimulus by pressing a left or right button, while wearing gloves of the same or different color as the stimuli. Participants performed the task individually, either by responding to either stimulus shapes (Experiment 1) or by responding to only 1 of the 2 shapes (Experiment 2), and in the presence of a coactor. Congruence between stimulus and glove color affected performance in the 2-choice and the joint tasks but not in the individual go/no-go task. This demonstration of a nonspatial JSE is inconsistent with the spatial response coding approach but supports the referential coding approach.

Joint Simon effects for non-human co-actors

“…Our finding that the cSE is modulated by the type of response mode but not by the type of co-actor suggests that the perceived similarity between both actors can also be induced by procedural aspects of the task, like the way in which action events are delivered, and not only by perceptual features of the event (Sellaro, Dolk, Colzato, Liepelt, & Hommel, 2015). These procedural aspects of the task relating to event production had a stronger impact on joint task performance than the physical appearance or humanness of the interaction partner.…”

Is it me or is it you? Behavioral and electrophysiological effects of oxytocin administration on self-other integration during joint task performance

“…Perceived similarity between ones' own and other's generated events determines the need to use the spatial dimension as a reference frame. This perceived similarity can be present at a perceptual level, i.e., similarity between the participant's and the co-actor's action effects (Sellaro, Dolk, Colzato, Liepelt, & Hommel, 2015), but it can also exist on more abstract levels such as the similarity in personal relationship between both actors (Stenzel et al). Previous research has indeed shown that both non-social (e.g., a metronome or a Japanese waving cat; Dolk et al, 2013) and social factors such as the friendliness of the co-actor (Hommel, Colzato, & van den Wildenberg, 2009), interdependency (Colzato, de Bruijn, & Hommel, 2012), and social exclusion (Costantini & Ferri, 2013) may modulate the size of the SSE.…”

Theory of mind and joint action in Parkinson’s disease

“…This is in line with the findings reported by Humphreys and Bedford (2011) in frontal patients. According to the referential coding account, a joint action task requires the coding of self-own action (I-go) and other-own action (You-go), especially in a turn-taking response as in the present study (Dolk et al, 2011(Dolk et al, , 2013Hommel, 2009Hommel, , 2011Hommel et al, 2001Liepelt et al, 2011, 2013Prinz, 2015;Sellaro et al, 2015;Stenzel & Liepelt, 2016). In other words, the joint action task induces a response-selection conflict between self-own action and other-own action when a target is presented.…”

“…However, the action co-representation account for the joint compatibility effect has recently been challenged (Dittrich, Bossert, Rothe-Wulf, & Klauer, 2017;Dittrich, Dolk, Rothe-Wulf, et al, 2013;Dittrich, Rothe, & Klauer, 2012;Dolk, Hommel, Prinz, & Liepelt, 2013, 2014aDoneva & Cole, 2014;Guagnano, Rusconi, & Umiltà, 2010;Hommel, Colzato, & van den Wildenberg, 2009;Klempova & Liepelt, 2015;Liepelt, Wenke, Fischer, & Prinz, 2011;Müller, Brass, Kühn, et al, 2011a;Porcu, Bölling, Lappe, & Liepelt, 2016;Puffe, Dittrich, & Klauer, 2017;Sellaro, Dolk, Colzato, et al, 2015;Stenzel & Liepelt, 2016; see Dolk, Hommel, Colzato et al, 2011, 2014b. One of these recent alternative accounts is the referential coding account (Dolk et al, 2011(Dolk et al, , 2013(Dolk et al, , 2014a, which offers a plausible explanation for modulations of the joint Simon effect in a number of observations, such as group membership (i.e., in-group vs. out-group; Müller, Kühn, van Baaren et al, 2011b) or the presence of a joint Simon effect in presence of nonhuman co-actors (e.g., Japanese waving cat: Dolk et al, 2013) compared with the action co-representation account.…”