<qa>  What is the major cause of disability worldwide?Cerebrovascular disease is a major cause of disability worldwide. The catastrophic burden of stroke is more dramatic in low- and middle- income countries, and the scarcity of evidence-based rehabilitation interventions represents a major challenge to global health care. Upper limb weakness is frequent after stroke, but there is no universally accepted treatment to effectively improve hand function in patients with moderate and severe motor impairment. These are the patients in deepest need of rehabilitative interventions. This project addresses this important issue, by testing effects of a novel approach. The investigators will non-invasively stimulate peripheral nerves in order to enhance effects of motor training aided by an electrical stimulation device in patients with moderate to severe hand weakness. Our hypothesis is that peripheral nerve stimulation will enhance effects of motor training in patients in the chronic stage after stroke. 