Overview

This pilot study for stroke patients with chronic upper limb hemiplegia will examine the effects of non-invasive brain stimulation and neuromuscular electrical stimulation on hand motor control and corticospinal excitability. Specifically, this study will investigate the effects of timing and delivery of tDCS in conjunction with contralaterally controlled functional electrical stimulation.

Eligibility

Inclusion Criteria:

1. Age ≥ 21
2. ≥ 6 months since first clinical hemorrhagic or nonhemorrhagic stroke
3. Able to follow 3-stage commands and remember 2 of 3 items after 30 minutes
4. Full volitional elbow extension/flexion and hand opening/closing of unaffected limb
5. Adequate active movement of shoulder and elbow to position the paretic hand in the workspace for table-top task practice
6. Patient must be able to sit unassisted in an armless straight-back chair for the duration of the screening portion of the eligibility assessment
7. Medically stable
8. ≥ 10° finger extension
9. Unilateral upper limb hemiparesis with finger extensor strength of ≤ grade 4/5 on the manual muscle test AND a score of

   ≥1 and ≤ 11/14 on the hand section of the upper extremity Fugl-Meyer Assessment

10. Skin intact on hemiparetic arm, hand and scalp
11. While relaxed, surface neuromuscular electrical stimulation of finger extensors and thumb extensors and/or abductors produces a functional degree of hand opening without pain.
12. No significant visual or hearing impairment

Exclusion Criteria:

1. Co-existing neurological condition other than prior stroke involving the hemiparetic upper limb (e.g., peripheral nerve injury, Parkinson's disease, spinal cord injury, traumatic brain injury, multiple sclerosis).
2. Uncontrolled seizure disorder
3. Use of seizure lowering threshold medications at the discretion of the study physician (Dr. Rich Wilson)
4. Cardiac pacemaker or other implanted electronic device and/or stent
5. Pregnant
6. Intramuscular botox injections in any upper extremity muscle in the last 3 months
7. Insensate arm, forearm, or hand
8. Severely impaired cognition and communication
9. Uncompensated hemi-neglect (extinguishing to double simultaneous stimulation)
10. Severe shoulder or hand pain (unable to position hand in the workspace without pain)
11. Metal implant in the head