RESUMEN
During social interactions we often have an automatic and unconscious tendency to copy or 'mimic' others' actions. The dominant view on the neural basis of mimicry appeals to an automatic coupling between perception and action. It has been suggested that this coupling is formed through associative learning during correlated sensorimotor experience. Although studies with adult participants have provided support for this hypothesis, little is known about the role of sensorimotor experience in supporting the development of perceptual-motor couplings, and consequently mimicry behaviour, in infancy. Here we investigated whether the extent to which an observed action elicits mimicry depends on the opportunity an infant has had to develop perceptual-motor couplings for this action through correlated sensorimotor experience. We found that mothers' tendency to imitate their 4-month-olds' facial expressions during a parent-child interaction session was related to infants' facial mimicry as measured by electromyography. Maternal facial imitation was not related to infants' mimicry of hand actions, and instead we found preliminary evidence that infants' tendency to look at their own hands may be related to their tendency to mimic hand actions. These results are consistent with the idea that mimicry is supported by perceptual-motor couplings that are formed through correlated sensorimotor experience obtained by observing one's own actions and imitative social partners.