Action representations and associated disorders

Actions are represented in the brain as a way to predict and simulate the dynamics of body movements and interactions with the environment prior to their execution. Although action representations can be voluntarily produced (e.g. when mentally rehearsing a movement), in most cases they are activated automatically, and their content may not be fully available to conscious experience. Nevertheless, they play a major role in the execution of skilled movements and contribute to our comprehension of other people's actions. Unsurprisingly, disruption of action representations leads to severe difficulties in actual and pantomimed tool use, causes impairments in performing motor imagery tasks and in understanding and imitating gestures.