VR-based Action Observation Treatment for Upper Limb Rehabilitation in Stroke: a Multimodal Study.

The loss of upper-limb motor functioning due to ischemic stroke has a negative impact on quality of life of patients. Action Observation Treatment (AOT), recently developed based on the mirror mechanism functioning, has proved effective in promoting plasticity into the motor system, ultimately boosting the motor recovery. The use of virtual reality further empowers the effectiveness of AOT, making the visual experience more first-person, and thus more realistic. A complete picture of the neurobiological mechanisms underlying AOT effectiveness is lacking to date, including the neuroradiological and biohumoral markers modulated by AOT, and their role in predicting the clinical outcome. Starting from these premises, the investigators propose a study aiming at evaluating the AOT effectiveness in post-stroke patients, and at identifying the biomarkers indexing the motor recovery process. Sixty patients affected by ischemic stroke will be enrolled at Humanitas Clinical and Research Center IRCCS (ICH) Stroke Unit will be included and randomized in the following groups: * VR-AOT: experimental group, observing actions in virtual reality * VR-LO: control groups, observing a matched dose of videos depicting landscapes in virtual reality. Clinical, neuroimaging and biohumoral evaluations, performed at Screening (Ts), Basal visit (T0), end-of-treatment (T1), 2 months follow up (FU-2), will include the following endpoints: Fugl-Meyer upper extremity motor scale (FM-UE); Nine-hole-peg test; Box and block test; Modified Ashworth scale; MRC; Pain Numeric-rating-scale; Functional Independence measure. Patients will undergo treatment sessions for 6 weeks (5 days/week). VR-AOT patients will observe in virtual reality -rehearse and execute specific upper limb motor task belonging to activities of daily living. VR-LO participants will observe virtually explorable landscapes lasting for a matched duration. Then, participants will be asked to actively perform the same set of hand actio