@article{StenzelDolkColzatoetal.2014,
  author    = {Stenzel, Anna and Dolk, Thomas and Colzato, Lorenza S. and Sellaro, Roberta and Hommel, Bernhard and Liepelt, Roman},
  title     = {The joint Simon effect depends on perceived agency, but not intentionality, of the alternative action},
  series = {Frontiers in human neuroscienc},
  volume    = {8},
  journal   = {Frontiers in human neuroscienc},
  publisher = {Frontiers Research Foundation},
  address   = {Lausanne},
  issn      = {1662-5161},
  doi       = {10.3389/fnhum.2014.00595},
  pages     = {10},
  year      = {2014},
  abstract  = {A co-actor's intentionality has been suggested to be a key modulating factor for joint action effects like the joint Simon effect (JSE). However, in previous studies intentionality has often been confounded with agency defined as perceiving the initiator of an action as being the causal source of the action. The aim of the present study was to disentangle the role of agency and intentionality as modulating factors of the JSE. In Experiment 1, participants performed a joint go/nogo Simon task next to a co-actor who either intentionally controlled a response button with own finger movements (agency+/intentionality+) or who passively placed the hand on a response button that moved up and down on its own as triggered by computer signals (agency-/intentionality-). In Experiment 2, we included a condition in which participants believed that the co-actor intentionally controlled the response button with a Brain-Computer Interface (BCI) while placing the response finger clearly besides the response button, so that the causal relationship between agent and action effect was perceptually disrupted (agency-/intentionality+). As a control condition, the response button was computer controlled while the co-actor placed the response finger besides the response button (agency-/intentionality-). Experiment 1 showed that the JSE is present with an intentional co-actor and causality between co-actor and action effect, but absent with an unintentional co-actor and a lack of causality between co-actor and action effect. Experiment 2 showed that the JSE is absent with an intentional co-actor, but no causality between co-actor and action effect. Our findings indicate an important role of the co-actor's agency for the JSE. They also suggest that the attribution of agency has a strong perceptual basis.},
  language  = {en}
}
@misc{DolkHommelColzatoetal.2014,
  author    = {Dolk, Thomas and Hommel, Bernhard and Colzato, Lorenza S. and Schuetz-Bosbach, Simone and Prinz, Wolfgang and Liepelt, Roman},
  title     = {The joint Simon effect a review and theoretical integration},
  series = {Frontiers in psychology},
  volume    = {5},
  journal   = {Frontiers in psychology},
  publisher = {Frontiers Research Foundation},
  address   = {Lausanne},
  issn      = {1664-1078},
  doi       = {10.3389/fpsyg.2014.00974},
  pages     = {10},
  year      = {2014},
  language  = {en}
}
@article{HartmannFischerMast2019,
  author    = {Hartmann, Matthias and Fischer, Martin H. and Mast, Fred Walter},
  title     = {Sharing a mental number line across individuals? The role of body position and empathy in joint numerical cognition},
  series = {The quarterly journal of experimental psychology},
  volume    = {72},
  journal   = {The quarterly journal of experimental psychology},
  number    = {7},
  publisher = {Sage Publ.},
  address   = {London},
  issn      = {1747-0218},
  doi       = {10.1177/1747021818809254},
  pages     = {1732 -- 1740},
  year      = {2019},
  abstract  = {A growing body of research shows that the human brain acts differently when performing a task together with another person than when performing the same task alone. In this study, we investigated the influence of a co-actor on numerical cognition using a joint random number generation (RNG) task. We found that participants generated relatively smaller numbers when they were located to the left (vs. right) of a co-actor (Experiment 1), as if the two individuals shared a mental number line and predominantly selected numbers corresponding to their relative body position. Moreover, the mere presence of another person on the left or right side or the processing of numbers from loudspeaker on the left or right side had no influence on the magnitude of generated numbers (Experiment 2), suggesting that a bias in RNG only emerged during interpersonal interactions. Interestingly, the effect of relative body position on RNG was driven by participants with high trait empathic concern towards others, pointing towards a mediating role of feelings of sympathy for joint compatibility effects. Finally, the spatial bias emerged only after the co-actors swapped their spatial position, suggesting that joint spatial representations are constructed only after the spatial reference frame became salient. In contrast to previous studies, our findings cannot be explained by action co-representation because the consecutive production of numbers does not involve conflict at the motor response level. Our results therefore suggest that spatial reference coding, rather than motor mirroring, can determine joint compatibility effects. Our results demonstrate how physical properties of interpersonal situations, such as the relative body position, shape seemingly abstract cognition.},
  language  = {en}
}
@misc{GianelliGentilucci2018,
  author    = {Gianelli, Claudia and Gentilucci, Maurizio},
  title     = {Editorial: Reaching to Grasp Cognition: Analyzing Motor Behavior to Investigate Social Interactions},
  series = {Frontiers in psychology},
  volume    = {9},
  journal   = {Frontiers in psychology},
  publisher = {Frontiers Research Foundation},
  address   = {Lausanne},
  issn      = {1664-1078},
  doi       = {10.3389/fpsyg.2018.01236},
  pages     = {2},
  year      = {2018},
  language  = {en}
}