Motor mimicry supports the decoding of perceived emotions by the healthy brain1,2. Viewing emotional facial expressions rapidly and involuntarily engages the facial muscles of neurologically normal observers3,4. Emotional mimesis may have evolved as a specialized ‘exaptation’ of action observation, and by promoting emotional contagion and affective valuation may have facilitated the development of advanced human social behaviour and theory of mind2,5,6. In line with this interpretation, motor recoding of observed emotion correlates with empathy and emotion identification ability7 and predicts authenticity judgments on facial expressions8; while conversely, facial paralysis induced by botulinum toxin attenuates emotional reactivity9. The linkage between emotion observation, recognition and mimesis is precise: viewing of universal facial emotional expressions10 produces signature profiles of electromyographic (EMG) activity in the facial muscles conveying each expression3,11. This phenomenon is mediated by distributed, cortico-subcortical brain regions that may together instantiate a hierarchically organised neural substrate for inferring the intentions and subjective states of others12–15: primary visual representations of emotions would comprise the lowest level of the hierarchy, ascending through sensorimotor representations of emotional movement kinematics, prediction of movement goals and affective states, and encoding of intentions, including affective mentalising.