Temporal binding effect in the action observation domain: Evidence from an action-based somatosensory paradigm

Temporal binding is understood as an effect in which a temporal interval between a voluntary action and its consequent effect is perceived as compressed. It denotes an implicit measure of a sense of agency. When people observe someone else performing an action that generates an effect, temporal binding also takes place. We aimed to test whether the interaction between observed actions and tactile sensation influences temporal binding. Participants observed finger tapping movements (of a human or wooden hand), in parallel to receiving tactile stimulations on their fingertip. These stimulations were either congruent or incongruent with the tactile consequences of the observed movement. The finger tapping movement was followed by a tone. Participants estimated the intervals between the observed action and the tone. We found that temporal binding for observed actions depends on the congruency between the perceived touch and tactile consequences of observed actions restricted to intentional actors.