Neurophysiological and Kinematic Predictors of Response in Chronic Stroke

The purpose of this study is to design a predictive model of stroke recovery based on baseline measurements of arm movement and brain physiology. The expectation is the development of a formula to predict a person's response to an arm rehabilitation program provided in the chronic phase (6 months or greater post stroke) of recovery. The study will include magnetic resonance imaging (MRI), transcranial magnetic stimulation (TMS), genetic testing using blood and saliva, and an arm exercise program consisting of robot-assisted exercise combined with functional arm exercise called transition to task training (TTT).

After informed consent, a baseline neurological exam, medical records review, MRI of the brain, TMS, questionnaires, cognitive testing, robot evaluations, and arm function testing will occur. Baseline testing will occur in the first 4-6 weeks of participation including two separate sessions approximately 1 week a part to examine arm strength, range of motion, and ability to perform functional tasks, with one additional session if needed to verify stability between results. Additionally, one robot evaluation, one MRI, and one TMS session will be completed. We will also collect genetic data using blood and saliva samples to examine potential RNA expression and genetic polymorphisms that might influence response to therapy.

The intervention phase consists of 12 weeks of robot and transition to task arm exercise training (TTT). Interventions will occur approximately 3 times per week for 12 weeks for a total of 36 visits. Additional time and visits will be allowed with visits occurring 4 times per week or up to 6 additional weeks (not to exceed 18 weeks) if scheduling conflicts arise. The intervention sessions will be one hour in duration.

During the hour-long intervention, 45 minutes of robotic intervention will be followed by 15 minutes of TTT. Two separate robots targeting different movements will be used for the 3 phases of the robot training. The training will be sequential with 12 sessions completed on the wrist robot, followed by 12 sessions on the shoulder-elbow robot and the final 12 sessions alternating between the wrist and elbow-shoulder robot.

After the final training session, subjects will return after a 12 week retention period. At various time points during and after the intervention phase there will be additional arm function testing, robot evaluations, questionnaires, blood draws, and TMS sessions to re-assess ability.

Eligibility Criteria:
Inclusion Criteria:

* Clinically defined, unilateral, hemiparetic stroke with radiologic exclusion of other possible diagnosis
* Stroke onset at least 6 months before enrollment
* Present with Mild/Moderate to Severe arm dysfunction (based on Fugl-Meyer scores of 10 to 45)
* Be medically stable to participate in the study and not have contractures or other impairments that would interfere with the interventional training.

Exclusion Criteria:

* Unable to give informed consent
* Have a serious complicating medical illness that would preclude participation.
* Contractures or orthopedic problems limiting range of joint motion in the potential study arm
* Visual loss such that the subject would not be able to see the test patterns on the robot computer monitor
* Botulinum toxin to study arm within four months of study enrollment or if received during the study period
* Unable to comply with requirements of the study
* Participants with a history of a seizure will not be precluded from the study, but will not be enrolled in the TMS portions
* Participants with electromagnetic exclusions (metal implants in the cranium, implanted electronic devices etc.) will not be precluded from the study but will be excluded from the MRI and TMS portions