Action execution engages human mirror neuron system more than action observation.

The existence of mirror neurons in Macaque monkeys helps to explain many social abilities of primates. Controversy exists, however, over whether human functional brain measures reveal mirror neuron activity. Claims have been made that measures such as electroencephalographic μ suppression reflect a human mirror neuron system such as that seen in monkeys, but more data are needed to support these claims. Here we report significantly greater μ suppression for participants' execution of an action compared with observation of the same action, similar to the pattern seen in monkeys. Current data therefore support the claim that electroencephalographic μ suppression reflects mirror neuron activity in humans.