Grasping intentions: from thought experiments to empirical evidence

Skepticism has been expressed concerning the possibility to understand others' intentions by simply observing their movements: since a number of different intentions may have produced a particular action, motor subormation-it has been argued-might be sufficient to understand what an agent is doing, but not her remote goal in performing that action. Here we challenge this conclusion by showing that in the absence of contextual subormation, intentions can be suberred from body movement. Based on recent empirical findings, we shall contend that: (1) intentions translate into differential kinematic patterns; (2) observers are especially attuned to kinematic subormation and can use early differences in visual kinematics to anticipate the intention of an agent in performing a given action; (3) during interacting activities, predictions about the future course of others' actions tune online action planning; (4) motor activation during action observation subtends a complementary understanding ...