Previous research has shown that performing joint actions can lead to the representation of both one's own and others' actions. In the present study we explored the influence of co-representation on response stopping. Are joint actions more difficult to stop than solo actions? Using a variation of the stop-signal task, we found that participants needed more time to stop a planned joint action compared with a planned solo action (Experiment 1). This effect was not observed when participants performed the task in the presence of a passive observer (Experiment 2). A third transcranial magnetic stimulation experiment (Experiment 3) demonstrated that joint stopping recruited a more selective suppression mechanism than solo stopping. Taken together, these results suggest that participants used a global inhibition mechanism when acting alone; however, they recruited a more selective and slower suppression mechanism when acting with someone else.
Keywords: action co-representation; joint stopping; motor evoked potentials; transcranial magnetic stimulation.
© 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.