Interpreting actions: The goal behind mirror neuron function

Crucial to our everyday social functioning is an ability to interpret the behaviors of others. This process involves a rapid understanding of what a given action is not only in a physical sense (e.g., a precision grip around the stem of a wine glass) but also in a semantic sense (e.g., an invitation to “cheers”). The functional properties of fronto-parietal mirror neurons (MNs), which respond to both observed and executed actions, have been a topic of much debate in the cognitive neuroscience literature. The controversy surrounds the role of the “mirror neuron system” in action understanding: do MNs allow us to comprehend others' actions by allowing us to internally represent their behaviors or do they simply activate a direct motor representation of the perceived act without recourse to its meaning? This review outlines evidence from both human and primate literatures, indicating the importance of end-goals in action representations within the motor system and their predominance in influencing action plans. We integrate this evidence with recent views regarding the complex and dynamic nature of the mirror neuron system and its ability to respond to broad motor outcomes.