Mirror neurons in the macaque are equally active when the animal initiates an action and when the animal observes another take the same or similar action. These neurons may be used in goal recognition (I recognize the goal of your action through resonance of that part of my motor system used by me to accomplish a particular goal), inferring intent, empathy, and, in general, greasing the wheels of social interaction. I describe in this chapter a new methodology for investigating mirror mechanism function: because some mirror neurons are part of the motor system they can be adapted through repeated action; and, because mirror neurons are multimodal, the effect of that adaptation can be shown in other cognitive tasks, thereby demonstrating the causal effect of the mirror mechanism on that other cognitive task.