After a stroke, it is very common to lose the ability to open the affected hand. Occupational and physical rehabilitation therapy (OT and PT) combined with non-invasive brain stimulation may help a person recover hand movement.

The purpose of this study is to compare 3 non-invasive brain stimulation protocols combined with therapy to see if they result in different amounts of recovery of hand movement after a stroke.

This study is a randomized clinical trail (RCT) of stroke survivors with chronic (6 to 24 months) hemiplegia randomized to: 1) conventional transcranial direct current stimulation (tDCS), 2) unconventional tDCS, or 3) sham tDCS during contralaterally controlled functional electrical stimulation mediated occupational therapy. The treatment will last 12 weeks and be followed by a 6-month follow-up period. Assessors, therapists and participants will be blinded to which tDCS treatment is received. This will be the first RCT of tDCS + CCFES.

Inclusion Criteria:

1. Age ≥ 21 and ≤ 90
2. ≥ 6 and ≤ 24 months since first clinical hemorrhagic or nonhemorrhagic stroke
3. Able to follow 3-stage command
4. Able to remember 2 of 3 items after 30 minutes
5. Full volitional elbow extension/flexion and hand opening/closing of unaffected limb
6. Adequate active movement of shoulder and elbow to position the paretic hand in the workspace for table-top task practice
7. Patient must be able to sit unassisted in an armless straight-back chair for the duration of the screening portion of the eligibility assessment
8. Medically stable
9. ≥ 10° finger and wrist extension
10. Skin intact on hemiparetic arm, hand and scalp
11. Muscle contraction can be elicited with Transcranial Magnetic Stimulation
12. Unilateral upper limb hemiparesis with finger extensor strength of ≤ grade 4/5 on the Medical Research Council (MRC) scale
13. Score of ≥1/14 and ≤ 11/14 on the hand section of the upper extremity Fugl-Meyer Assessment
14. While relaxed, surface NMES of finger extensors and thumb extensors and/or abductors produces a functional degree of hand opening without pain.

Exclusion Criteria:

1. Co-existing neurological condition other than prior stroke involving the hemiparetic upper limb (e.g., peripheral nerve injury, PD, SCI, TBI, MS).
2. Uncontrolled seizure disorder
3. Use of seizure lowering threshold medications and the discretion of the study physician
4. Cardiac pacemaker or other implanted electronic device
5. Pregnant
6. IM Botox injections in any UE muscle in the last 3 months
7. Insensate arm, forearm, or hand
8. Deficits in communication that interfere with reasonable study participation
9. Severely impaired cognition and communication
10. Uncompensated hemi-neglect (extinguishing to double simultaneous stimulation)
11. Severe shoulder or hand pain (unable to position hand in the workspace without pain)