A proposal for new neurorehabilitative intervention on Moebius Syndrome patients after ‘smile surgery’. Proof of concept based on mirror neuron system properties and hand-mouth synergistic activity

Congenital facial palsy and emotion processing: The case of Moebius syndrome

“…Nevertheless, a new neurorehabilitation treatment (FIT-SAT, Figure 1) that exploits the properties of the MNS (in particular, the action observation therapy 95 ) and the synergies between the hand and the mouth 96 seems to be effective in facilitating the activation of the motor programs involved in the control of the transplanted muscle, permitting the achievement of a spontaneous and naturalistic smile. 94 Although these preliminary data are encouraging, it will be needed to include a greater number of patients to confirm the efficacy of the FIT-SAT treatment. It is clear that MBS is a complex syndrome that requires the synergistic activity of different specialists (speech therapists, surgeons, etc.…”

“…22,92 The microneuromuscular transfer surgical technique consists in transplanting the gracilis muscle to the face and innervating it by a donor nerve, usually the masseteric nerve (V CN) that is responsible for chewing movements. 22,92 About 3 to 6 months after smile surgery, 94 the first contraction of the transplanted muscle appears, but the use of the masseteric nerve results in a not completely emotional smile. In fact, the trigeminal nerve is a nerve responsible for sensation in the face and motor functions such as biting and chewing, and it cannot replace volitional movement and emotional animation.…”

“…102 When individuals observe the facial expression of another person, they would mimic that facial expression (through a subthreshold facial muscles activation) and this initial process would be at the basis of emotion recognition. 80 94 ; SAT refers to the synergistic activity of hand closing while smiling should facilitate the activation of the cortical areas connected to the mouth. The hand contraction facilitates the recruitment of the Gracilis muscle as consequence of the activity of mouth motor neurons in motor cortical areas 94 existent literature, at least four models of simulation mechanisms can be taken into account for recognition of facial expressions.…”

“…80 94 ; SAT refers to the synergistic activity of hand closing while smiling should facilitate the activation of the cortical areas connected to the mouth. The hand contraction facilitates the recruitment of the Gracilis muscle as consequence of the activity of mouth motor neurons in motor cortical areas 94 existent literature, at least four models of simulation mechanisms can be taken into account for recognition of facial expressions. 8 All simulation models of emotion recognition propose that at least part of the mechanism by which we recognize others' emotional states relies on internally simulating the same emotional state in ourselves, emphasizing the utilization of body representations in both perception and imitation.…”

“…Progressively, further repetitions are gradually included until the patient is able to perform at least 10 successive repetitions and to maintain the smile posture for at least 3 seconds. (B) FIT combined action observation with the direct effects of action execution suggesting that the activation of motor areas by action observation becomes reinforced by the concomitant active execution of the observed actions; SAT refers to the synergistic activity of hand closing while smiling should facilitate the activation of the cortical areas connected to the mouth. The hand contraction facilitates the recruitment of the Gracilis muscle as consequence of the activity of mouth motor neurons in motor cortical areas …”