Recent findings that brain circuits involved in action are also activated during action observation have given rise to the hypothesis that understanding the actions of others involves the activation, in the observer, of motor representations that match those of the actor. In our 2003 study, we provided the first direct evidence for this direct-matching hypothesis. We showed that when people observe a simple block stacking task, the coordination between their gaze and the actor’s hand is the same as the coordination between the actor’s gaze and hand. Thus, people run the same eye movement programs in action and action observation.

The following video clip shows an individual's gaze (white cross) when they perform the block stacking task, observe an actor performing the task, and then observe the blocks being moved by an unseen actor.

In action and action observation, people fixate grasp sites and landing sites in a predictive fashion such that gaze arrives before the hand and then departs at about the same time. In contrast, when observing blocks moving alone, reactive eye movements are seen with gaze often tracking the moving blocks.

For more information see: Flanagan JR, Johansson RS (2003) Action plans used in action observation Nature 424:769-771.

To read more about our work investigating action observation, see:

Rotman G, Troje NF, Johansson RS, Flanagan JR (2006) Eye movements when observing predictable and unpredictable actions Journal of Neurophysiology 96: 1358-1369.

Flanagan JR, Rotman G, Reichelt AF, Johansson RS (2013) The role of observers' gaze behavior when watching object manipulation tasks: predicting and evaluating the consequences of action Philosophical Transactions of the Royal Society B: Biological Science 368: 20130063.