van Rysewyk, S, The Contributions of Moebius Syndrome to Empathy, Psychology of Empathy, Nova Science Publishers, Inc., DJ Scalaletti (ed), New York, pp. 235-250. ISBN 9781612097947 (2011) [Research Book Chapter]
Human beings mimic a variety of behaviours, including emotional facial expressions. Embodied simulation theories propose that mimicry relies on internal simulation of perceived emotion to generate understanding and empathy. One influential application of embodied simulation theory, reverse simulation theory, predicts that the inability to make facial expressions results in the failure of emotion facial recognition and empathy. However, behavioral studies of Moebius Syndrome, a congenital condition of bilateral facial palsy and impaired lateral eye movement, show that individuals with Moebius can perform emotion recognition, and that facial mimicry does not play a causal role in such contexts. Hence, facial feedback is not the primary source of information that can be used for emotion recognition and empathy. In support of this, qualitative studies report that individuals with Moebius embody emotions in motor and vocal signals to engage in extended, rhythmic interactive patterns, during which active on-line understanding of another individual‟s emotions is acquired. Patterns currently known to be engaged in by Moebius individuals and their interactions partners include the negotiation of the next sequences of words or signals in a conversation, and the separation of intense emotions from fixed action responses. These embodied interactions also implicate empathy, since empathy relies on the ability to exchange emotions and meanings as signals with other individuals in a continuous manner. However, an individual with Moebius deprived of such experiences may not fully develop the resources and strategies that support empathy and emotion recognition. The relation between Moebius, autism and empathy is also discussed.