Novel Brain Neurotechnology for Optimizing Precision Mirror Therapy in Stroke

Inclusion Criteria: 1. ≥ 3 months onset from a first-ever unilateral stroke; 2. an initial FMA scores between 18 to 56, indicating moderate to mild upper extremity motor impairment (Thielman, Kaminski, \& Gentile, 2008); 3. age between 35 to 85; 4. no excessive spasticity in any of the joints of the affected arm (shoulder, elbow, wrist and fingers); 5. ability to follow instructions and perform tasks (Mini Mental State Examination scores ≥24); 6. no participation in any neurorehabilitation experiments or drug clinical trials and 7. willing to provide written informed consent. Exclusion Criteria: 1. contradiction to tRNS including a history of epilepsy, pregnant, having pacemakers and metallic implants in the neck and heads (Rossi, Hallett, Rossini, Pascual-Leone, \& Safety of, 2009); 2. History of drug or alcohol abuse(Rossi et al., 2009); 3. concomitant neurological conditions such as dementia, Parkinson's disease, brain tumor, brain injury and other brain diseases (such as intracranial hypertension or cerebral edema); 4. Botulinum toxin injections 3 months before enrollment 5. have unstable cardiovascular status such as uncontrolled hypertension or New York Heart Association (NYHA) Class III/IV heart failure or are not suitable for receiving tRNS by the physician's assessments.