Spatial distribution and temporal evolution of EEG alpha rhythms related to sensory-motor tasks during Mirror Visual Feedback illusion

Placing a mirror adequately oriented, unilateral movements produce the illusion of the opposite limb moving synchronously. This Mirror Visual Feedback (MVF) illusion has been proposed to promote neurorehabilitation in patients with chronic pain conditions and motor deficits. However, the cortical areas and the mechanisms related to this illusory phenomenon are poorly understood. Through the analysis of the EEG alpha rhythms, the present PhD project aims to investigate the neurophysiological mechanisms underlying the MVF-induced illusion of finger movements and its effects on nociceptive processes. In the first part of the work, unilateral movements of the index finger during MVF were associated with a bi-hemispheric activity of the central sensory-motor cortical areas. Moreover, the source estimation of the EEG alpha oscillations unveiled the involvement of the premotor and posterior parietal associative cortical areas as responsible for visuomotor integration during MVF illusion. In the second part, sensory-motor interaction between MVF-induced illusory movements and electrical stimulations indicated that the inhibition of the midline limbic regions is associated with an individually lower perception of the stimulation intensity. A better understanding of these mechanisms might be relevant to developing therapies for those patients with unilateral limb impairment.