recoveriX PRO system is a Brain-Computer Interface (BCI) device that combines Motor Imagination (MI), with Functional Electrical Stimulation (FES) and Virtual Reality (VR) as feedback devices. The user wears an electroencephalography (EEG) cap that registers the neural activity during the mental practice. This system allows the user to control the feedback devices (FES +VR) with the MI. The goal of this clinical trial is to know the safety and clinical effectiveness of recoveriX-based treatment for improving motor functions in Parkinson's Disease patients. Researchers will compare the functional results obtained by recoveriX system, to the standard treatment based in FES + VR + MI without monitoring the EEG activity. The questions to answer are: 1. Will Parkinson's patients who undergo recoveriX therapy significantly improve their motor functions? 2. Is the functional improvement achieved with the BCI treatment superior to the standard MI+FES+VR treatment? 3. Is the recoveriX-based therapy as safe as the standard treatment? Participants will have to perform a complete assessment to evaluate their functionality before and after the intervention (motor skills, walking ability, fatigue, impact of the disease in daily living activities). Patients in the BCI group will receive 6 sessions per week during 4 weeks of BCI training with FES and VR feedback (24 sessions in total). Patients in the control group receive 6 sessions of FES + VR therapy per week for 4 weeks (24 sessions in total). Patients in the control group will receive the same instructions as the experimental but will not wear the EEG cap.