This study examines the effect of non-invasive brain stimulation targeting different brain areas on movement of the affected arm post-stroke. Participants will receive stimulation to each of 3 different brain areas combined with a session of arm exercise.

Small improvements in affected arm movement can be made with intensive physical practice. These improvements could potentially be enhanced by combining non-invasive brain stimulation with practice.

To develop such an intervention, it is necessary to understand which brain areas should be stimulated in which types of patients. It is probably more beneficial to target one side of the brain vs. the other, for example, depending on the characteristics of the stroke.

This study will examine the effect of stimulating one side of the brain vs. the other on the amount of improvement that occurs from physically practicing functional arm movements.

Inclusion Criteria:

• More than 6 months post-stroke
• Loss of voluntary finger movement in the affected hand
• Some voluntary movement of affected shoulder and/or elbow

Exclusion Criteria:

• Brainstem or cerebellar stroke
• Severe cognitive or language deficits
• Epilepsy or other seizure disorder
• Central nervous system disease or disorder other than stroke

The individual that conducts the tests of arm movement will be unaware of which brain area was stimulated.