Inclusion Criteria:  Able-bodied participants: good general health normal or corrected vision no history of neurological/psychiatric disease ability to read and understand English (Research Personnel do not speak Spanish) Subjects with motor disabilities motor deficits due to: unilateral and bilateral stroke / spinal cord injury / motor neuron diseases (i.e. amyotrophic lateral sclerosis, spino-cerebellar ataxia, multiple sclerosis) / muscular diseases (i.e. myopathy) / traumatic or neurological pain / movement disorders (i.e. cerebral palsy) / orthopedic / traumatic brain injury / brain tumors normal or corrected vision ability to read and understand English (Research Personnel do not speak Spanish) ability to provide informed consent  Exclusion Criteria:  Subjects with motor disabilities short attentional spans or cognitive deficits that prevent to remain concentrated during the whole experimental session heavy medication affecting the central nervous system (including vigilance) concomitant serious illness (e.g., metabolic disorders) All participants factors hindering EEG/EMG acquisition and FES/tdCS/tACS delivery (e.g., skin infection, wounds, dermatitis, metal implants under electrodes) criteria identified in safety guidelines for MRI and TMS, in particular metallic implants