How “social” is the social Simon effect?

Abstract

In the standard Simon task, participants carry out spatially defined responses to non-spatial stimulus attributes. Responses are typically faster when stimulus location and response location correspond. This effect disappears when a participant responds to only one of the two stimuli and reappears when another person carries out the other response. This social Simon effect (SSE) has been considered as providing an index for action co-representation. Here, we investigated whether joint-action effects in a social Simon task involve mechanisms of action co-representation, as measured by the amount of incorporation of another person's action. We combined an auditory social Simon task with a manipulation of the sense of ownership of another person's hand (rubber hand illusion). If the SSE is established by action co-representation, then the incorporation of the other person's hand into one's own body representation should increase the SSE (synchronous > asynchronous stroking). However, we found the SSE to be smaller in the synchronous as compared to the asynchronous stroking condition (Experiment 1), suggesting that the SSE reflects the separation of spatial action events rather than the integration of the other person's action. This effect is independent of the active involvement (Experiment 2) and the presence of another person (Experiment 3). These findings suggest that the “social” Simon effect is not really social in nature but is established when an interaction partner produces events that serve as a spatial reference for one's own actions.

Avatars and arrows: Implicit mentalizing or domain-general processing?

“…Our results are congruent with those of other, recent studies questioning evidence of implicit mentalizing in adults (Dolk et al, 2011;Guagnano, Rusconi, & Umiltà, 2010;Heyes, under review). By showing that domain--general processes are sufficient to explain behavior that seems to involve mentalizing, these studies support the view that mentalizing -both implicit and explicit -may be less pervasive in human social life than psychologists and philosophers have traditionally assumed (Apperly, 2011).…”

Keys and seats: Spatial response coding underlying the joint spatial compatibility effect

“…However, by demonstrating a joint SCE in the vertical but not in the horizontal condition, the present results clearly falsify this assumption. Instead, the results are in line with a spatialcoding account (Dolk et al, 2011;Dolk, Hommel, et al, 2013;. Accordingly, the vertical seating arrangement prompted participants to code their responses vertically leading to an overlap of the vertical stimulus dimension and the vertically coded response, thus leading to a joint SCE.…”

“…Dittrich et al's (2012) results not only provided evidence for the spatial-coding account in general, but they also suggested that spatial response coding refers (also) to the spatial relation of coacting participants. As several researchers developing and investigating the spatial-coding account have concentrated on the spatial relation of response keys or the spatial relation of alternative action events (Dolk et al, 2011;Dolk, Hommel, et al, 2013;; but see Guagnano et al, 2010), the spatial relation of participants is an intriguing, so far often neglected, influencing factor on spatial response coding and in turn on joint SCEs, that will be further examined in the present work. Recent research already suggests that the role of responding agents might be a relevant factor for joint compatibility effects: Philipp and Prinz (2010) asked participants to respond to the color of a diamond that was placed on a task-irrelevant photo of the participant's face, a coacting friend's face, or an unknown face.…”

“…Recently, however, an increasing number of studies have challenged the idea of action/task co-representation by demonstrating that joint SCEs can be elicited via social and nonsocial events (e.g., by another agent or inanimate object; Dittrich, Rothe, & Klauer, 2012;Dolk, Hommel, Colzato, Schütz-Bosbach, Prinz, & Liepelt, 2011;Dolk, Hommel, Prinz, & Liepelt, 2013;Dolk, Liepelt, Prinz, & Fiehler, 2013;Guagnano, Rusconi, & Umiltà, 2010). To simplify matters, we will term this approach the spatial-coding account in the remainder of this article, although the ideas of spatial coding formulated in previous works have focused on different aspects.…”

“…2 Whereas the spatial response coding account proposed by is concerned with rather basal (bottom-up) mechanisms (the task set; e.g., the seating position is assumed to induce a specific coding of responses), the referential coding account introduced by Dolk and colleagues (Dolk et al, 2011;Dolk, Hommel, et al, 2013) focuses on more global mechanisms (spatial response coding is induced to discriminate between action alternatives). Therefore, the accounts are compatible and complementary to each other, but focus on rather different aspects.…”