La stimolazione magnetica transcranica ripetuta incide sul feedback facciale e sulle risposte comportamentali

[Autom. eng. transl.] The present research aims to investigate the autonomic (facial mimic) and behavioral variations in response to empathic situations. It has been hypothesized that the simulation process (or facial feedback) may be related to the empathic responses implemented by the subject and also that it may be supported by the activation of the prefrontal cortex. In order to investigate the effect of the emotional context, the sample was asked to observe and empathize with emotional stimuli (facial expressions) characterized by different emotional values (positive vs negative vs. neutral). During the task a high frequency rTMS (repeated transcranial magnetic stimulation) stimulation on the MPFC area was applied to induce an increase in the subject's performance. In fact both the autonomic indexes (EMG activity of the zygomatic muscle and the corrugator muscle) and the different behavioral responses (correct recognition, CRs; response times, RTs) turn out to be modulated by the activity from the MPFC. During the activation of the prefrontal areas (compared to the sham condition) an improvement in performance was observed. In particular it was found on the one hand with an increase in CRs and a reduction of RTs for the recognition of faces and on the other a greater EMG response specific for the different emotions. In particular the zygomatic muscle was found to be more responsive in the case of positive emotions (joy) while the activity of the corrugator muscle for the negative ones (disgust, anger and fear). A significant effect was also noted for negative and potentially adverse faces compared to positive and neutral ones. The results obtained suggest the presence of a "simulation" mechanism that intervenes in empathic contexts that includes both EMG and behavioral responses. This mechanism seems to be supported and regulated by the MPFC.