Error feedback does not change response strategies in a joint force detection task

When two partners perform a joint physical task, each of them experiences a force that sums together a component generated by the partner and another generated from the environment. To investigate whether subjects are able to distinguish these two components, we created a force perception task in which two partners indicate the direction of an external force applied to a rigid bar that they grasp from opposite ends. In a previous study we showed that dyads adopt different response strategies and that many do not split the external force in a manner that allows both subjects to experience a meaningful interaction force. Here, we investigated whether a visual feedback on the partner's and correct response let dyads learn how to best split the external force. We show that this is not the case and that the dyads' force sharing and response strategies were comparable to those of the previous experiment.