Reversible inactivation of the mirror neuron system in non-human primates using pharmacogenetics: in search for a causal role of mirror neurons in social cognition
Few discoveries in cognitive neurosciences over the last decades have had such an impact on the field as the discovery of mirror neurons. Initially discovered in a single premotor region in the monkey brain, research in the past 25 years have uncovered the existence of mirror neurons in numerous brain regions in different species (songbirds, monkeys and humans). While few people still doubt the existence of these neurons in the brain, the cognitive function(s) possibly mediated by these intriguing neurons however, is/are still at the center of a spirited debate. In songbirds, these neurons presumably play a social role in song recognition and imitation. In primates, it has been proposed that these neurons mediate an even more impressive array of social abilities, ranging from aiding in understanding other individuals motor actions and intentions, to imitation and language abilities, emotion understanding, theory-of-mind skills and empathy. Surprisingly, while we have a substantial knowledge of mirror neurons functional properties in the monkey brain, obtained mostly with electrophysiology, causal evidence of these mirror neurons’ involvement in certain aspects of social cognition is completely lacking in monkeys. Using state-of-the-art pharmacogenetical techniques (DREADDs) that allow reversible inactivation of multiple mirror neuron network nodes combined with functional imaging (fMRI), we will investigate the proposed mirror neuron system’s role in action understanding.