How do we understand the actions of other individuals if we can only hear them? Auditory mirror neurons respond both while monkeys perform hand or mouth actions and while they listen to sounds of similar actions [1Keysers C. Kohler E. Umiltá M.A. Nanetti L. Fogassi L. Gallese V. Audiovisual mirror neurons and action recognition.Exp. Brain Res. 2003; 153: 628-636Crossref PubMed Scopus (308) Google Scholar, 2Kohler E. Keysers C. Umiltá M.A. Fogassi L. Gallese V. Rizzolatti G. Hearing sounds, understanding actions: Action representation in mirror neurons.Science. 2002; 297: 846-848Crossref PubMed Scopus (1234) Google Scholar]. This system might be critical for auditory action understanding and language evolution [1Keysers C. Kohler E. Umiltá M.A. Nanetti L. Fogassi L. Gallese V. Audiovisual mirror neurons and action recognition.Exp. Brain Res. 2003; 153: 628-636Crossref PubMed Scopus (308) Google Scholar, 2Kohler E. Keysers C. Umiltá M.A. Fogassi L. Gallese V. Rizzolatti G. Hearing sounds, understanding actions: Action representation in mirror neurons.Science. 2002; 297: 846-848Crossref PubMed Scopus (1234) Google Scholar, 3Gallese V. Keysers C. Rizzolatti G. A unifying view of the basis of social cognition.Trends Cogn. Sci. 2004; 8: 396-403Abstract Full Text Full Text PDF PubMed Scopus (1406) Google Scholar, 4Keysers C. Gazzola V. Towards a unifying neural theory of social cognition.Prog. Brain Res. 2006; 156: 383-405Google Scholar, 5Keysers C. Perrett D.I. Demystifying social cognition: a Hebbian perspective.Trends Cogn. Sci. 2004; 8: 501-507Abstract Full Text Full Text PDF PubMed Scopus (442) Google Scholar, 6Rizzolatti G. Craighero L. The mirror-neuron system.Annu. Rev. Neurosci. 2004; 27: 169-192Crossref PubMed Scopus (5072) Google Scholar]. Preliminary evidence suggests that a similar system may exist in humans [7Aziz-Zadeh L. Iacoboni M. Zaidel E. Wilson S. Mazziotta J. Left hemisphere motor facilitation in response to manual action sounds.Eur. J. Neurosci. 2004; 19: 2609-2612Crossref PubMed Scopus (144) Google Scholar, 8Bangert M. Peschel T. Schlaug G. Rotte M. Drescher D. Hinrichs H. Heinze H.J. Altenmuller E. Shared networks for auditory and motor processing in professional pianists: evidence from fMRI conjunction.Neuroimage. 2006; 30: 917-926Crossref PubMed Scopus (386) Google Scholar, 9Fadiga L. Craighero L. Buccino G. Rizzolatti G. Speech listening specifically modulates the excitability of tongue muscles: a TMS study.Eur. J. Neurosci. 2002; 15: 399-402Crossref PubMed Scopus (606) Google Scholar, 10Pizzamiglio L. Aprile T. Spitoni G. Pitzalis S. Bates E. D'Amico S. Di Russo F. Separate neural systems for processing action- or non-action-related sounds.Neuroimage. 2005; 24: 852-861Crossref PubMed Scopus (90) Google Scholar]. Using fMRI, we searched for brain areas that respond both during motor execution and when individuals listened to the sound of an action made by the same effector. We show that a left hemispheric temporo-parieto-premotor circuit is activated in both cases, providing evidence for a human auditory mirror system. In the left premotor cortex, a somatotopic pattern of activation was also observed: A dorsal cluster was more involved during listening and execution of hand actions, and a ventral cluster was more involved during listening and execution of mouth actions. Most of this system appears to be multimodal because it also responds to the sight of similar actions. Finally, individuals who scored higher on an empathy scale activated this system more strongly, adding evidence for a possible link between the motor mirror system and empathy.