Representing actions through their sound.

Since the discovery of 'mirror neurons' in the monkey premotor and parietal cortex, an increasing body of evidence in animals and humans alike has supported the notion of the inextricable link between action execution and action perception. Although research originally focused on the relationship between performed and viewed actions, more recent studies highlight the importance of representing the actions of others through audition. In the first part of this article, we discuss animal studies, which provide direct evidence that action is inherently linked to multi-sensory cues, as well as the studies carried out on healthy subjects by using state-of-the-art cognitive neuroscience techniques such as functional magnetic resonance imaging (fMRI), event-related potentials (ERP), magnetoencephalography (MEG), and transcranial magnetic stimulation (TMS). In the second section, we review the lesion analysis studies in brain-damaged patients demonstrating the link between 'resonant' fronto-parieto-temporal networks and the ability to represent an action by hearing its sound. Moreover, we examine the evidence in favour of somatotopy as a possible representational rule underlying the auditory mapping of actions and consider the links between language and audio-motor action mapping. We conclude with a discussion of some outstanding questions for future research on the link between actions and the sounds they produce.