Aim 1. Determine whether higher-velocity finger tracking training improves hand function more than slower velocity training. Working hypotheses: The higher-velocity training will have significantly greater functional improvement compared to the lower-velocity training, as measured by standardized upper extremity functional tests (Jebsen Taylor test, Box & Block Test, and Finger extension force test)
Aim 2. Ascertain whether higher-velocity finger tracking training differentially induces cortical reorganization as compared to lower-velocity finger tracking training.
Working hypotheses: The higher-velocity training will have significantly greater cortical reorganization compared to the lower-velocity training, as measured by:
1. TMS - increased amplitude of motor evoked potentials (MEP) from paretic extensor digitorum muscle in response to paired-pulse TMS to ipsilesional primary motor area (M1).
2. fMRI - increased volume of activation, signal intensity, and laterality of ipsilesional M1.
Aim 3. Explore whether the functional improvements correlate with the cortical reorganization. Working hypotheses: The functional improvements will correlate with the cortical reorganization.
- Tracking training Behavioral
Intervention Desc: The paretic finger movement training at different velocities included two 5-week periods of five days per week, 2-hours per day phases. The frequency for the higher-velocity training is 0.8 Hz, whereas the lower frequency training is 4 times slower, at 0.2 Hz. The two periods are each followed by a 3-week baseline period. The subject is seated in front of a laptop computer with the paretic forearm resting on the arm of the chair in a quiet room at home. The position of the forearm is pronated. An electrogoniometer, composed of a potentiometer attached to a custom hand splint, is placed on the paretic index finger with the potentiometer centered at the metacarpophalangeal joint. To keep the training session time equal between the two training phases, the duration of each slow training trial is 5 sec, compared to 20 sec for each fast training trial. Ultimately, the total number of required finger extension/flexion training movements is equal between the two phases. ARM 1: Kind: Experimental Label: Slow tracking training ARM 2: Kind: Experimental Label: Fast tracking training
- Allocation: Randomized
- Masking: Single Blind (Outcomes Assessor)
- Purpose: Treatment
- Endpoint: Efficacy Study
- Intervention: Crossover Assignment
|Type||Measure||Time Frame||Safety Issue|
|Primary||Hand function improvement||taken at weekly intervals for the whole study length, 20 weeks.||No|
|Secondary||corticospinal excitability||taken at weekly intervals for the whole study length, 20 weeks.||No|
|Secondary||cognitive function||at the beginning and at the end of the study, which are 1st and 20th week.||Yes|