Anagrafe della ricerca

Spontaneous interpersonal synchronization is a ubiquitous phenomenon, but its neural substrates and physiological control laws are still unclear. Movement synchronization of people cooperating in a motor task and brain synchronization of socially interacting participants are well known phenomena. However, whether an unconscious synchronous movement is generated by a synchronization between the dyad’s brain activity, which propagates as a synchronous input to the periphery, is unknown. Moreover, current literature only provides indirect evidence of the effects of interpersonal brain synchronization in terms of motor performance improvement. In this project we propose two complementary approaches to investigate, for the first time, the neural substrates underlying the interpersonal coordination and its relationship with motor performance. We will first study, in two solo protocols, how cortically originated brain controls drive a motor action during isometric force generation tasks, by analyzing the common oscillations between EEG and EMG signals, both at the muscular and single motor unit levels. Then, two collaborative protocols, a static force generation task and a postural task, will probe how participants’ brain activity changes during motor interaction and whether human-human interaction induces participants’ brain activity and motor neuron firings synchronization. The effect of the collaboration will be assessed by comparing the brain networks identified during the cooperative task and a similar solo task. Interpersonal synchronization of the brain activity and of the motoneuron firing will be tested through coherence analyses. After having characterized the neurophysiological basis of interpersonal brain synchronization in the context of motor control, we will design a strategy to interfere with the activation of the underlying neural network by transcranial direct current stimulation (tDCS) in humans. tDCS is a non-invasive brain stimulation approach which exploits a low-intensity direct current (1-2 mA) stimulation thorough scalp-attached electrodes to modulate the activity of targeted cortical areas. Exploiting tDCS protocols that effectively modulate the interpersonal brain synchronization would allow to envisage its application in neurorehabilitation. The innovative and interdisciplinary research scheme proposed in this project will allow, for the first time, to study cortico-muscular coupling, both at the muscular and motorneuronal level, and to characterize the neural basis underlying inter-personal synchronization occurring during a human-human motor task. The approaches proposed in this project would lead to striking advancements in neuroscience, as well as to a potential definition of innovative paradigms for neurorehabilitation.