This group will observe videos depicting daily actions and afterwards they will execute the seen actions

This group will imagine motorically the same action as the first group and afterwards they will execute the imagined actions

This group will neither observe nor imagine actions, but simply observe videos with no motor content. Afterwards they will execute the same actions as in AOT and MI.

During action observation, participants observe different daily actions (e.g. reading a newspaper; drinking an espresso) divided into up to four motor segments.

to assess the change in the functional status of the patient, the Functional Independence Measure (FIM) will be used. FIM consists in a 7-point scale (1 = <25% independence; total assistance required, 7 = 100% independence), and it can detect changes in the patient's status in 18 categories, focusing on motor and cognitive function. Functional patients' status will assess before treatment, within one week after the end of the treatment (after treatment) and two months' follow up.

to assess the change in motor status of the patient, the Unified Parkinson's Disease Rating Scale (UPDRS) will be used, and it consists in a 5-point scale (0 = no signs; 4 = severe). UPDRS will be administered before treatment, within one week after the end of the treatment (after treatment) and two months' follow up.

to assess the change of patient's gait parameters, the kinematic analysis will be used (i.e. gait analysis). The gait analysis allows to detect fine-grain changes in kinematic parameters of the movement, through a non-invasive methodology. Gait analysis will be performed before treatment, within one week after the end of the treatment (after treatment) and two months' follow up.