Abstract
Theories like "common coding" suggest joint representations of action and perception, which implies a bidirectional coupling between these domains. Effects of perception on action are self-evident. Evidence for direct effects of action on perception arises from perceptual bistability: congruent movements stabilize the interpretation of an ambiguous stimulus. Can cognitive processes affect such action-to-perception transfer? Observers viewed a structure-from-motion cylinder of ambiguous motion direction. Prior to the ambiguous stimulus, we presented unambiguous versions that suggest a mechanical model on how the cylinder connects to a rod; in the "belt-drive" condition the rod rotated in the same direction as the cylinder, in the "gear-drive" condition in the opposing direction. Observers rotated a manipulandum either the same way as the rod (congruent instruction) or in the opposing way (incongruent instruction). In the "belt-drive" condition, the congruent instruction translates to congruency between perception and manual rotation. In the "gear-drive" condition, the congruent instruction translates to *in*congruency between perception and action. If the action-to-perception transfer is not influenced by the internal model of the underlying mechanics, we would find that congruent movement stabilizes the percept in both conditions. If, however, the effect depends upon cognitive assumptions, we would find a more stable percept with incongruent movement in the "gear-drive" condition. Results showed a significant interaction between the trained mechanical model and the action-to-perception transfer. While the congruency-effect was present in the "belt-drive" condition, no difference in either direction was found following the "gear-drive" training. This suggests that perceptual and cognitive congruency effects nullify each other. Hence, the observers' internal model of a machine's operation influences action-to-perception transfer.
Meeting abstract presented at VSS 2018