Perceptuomotor rules as prediction tools in (joint) action: The case of orientation perception

The human action system has a layered structure supporting a cascade of partially overlapping information processes in multiple, interlinked representational spaces. Apart from the mirror neuron system which through motor resonance mediates one's understanding of the action goals of one's partner, perceptuomotor rules like Fitts' law, the Isogony Principle, and sequencing heuristics provide further sources of prediction in (joint) action. The present study focuses on a perceptuomotor rule that describes how the orientation of framed, tilted objects is perceived and acted upon by individuals. In two experiments involving the Rod-and-Frame Illusion (RFI) participants were asked to perform delayed responses that consisted either of (1) making a perceptual judgment in a forced-choice paradigm, or (2) rotating and propelling a hand-held cylinder. Irrespective of response type, the effects of the RFI proved robust and constant. The relevance of the findings for prediction in joint-action tasks is discussed.