Efficacy and Time Dependent Effects of Transcranial Direct Current Stimulation (Tdcs) Combined with Mirror Therapy for Rehabilitation after Subacute and Chronic Stroke

Combining neuromodulation intervention with task-specific training has emerged as an innovative and important neurorehabilitation approach to facilitate sensorimotor recovery and daily functions for patients after stroke. Mirror therapy (MT) is a behavioral intervention that has been demonstrated to be effective for improving sensorimotor functions of the paretic limb in patients with subacute and chronic stroke. Transcranial direct current stimulation (tDCS), on the other hand, is a non-invasive neuromodulation technique that can excite or inhibit neuronal activity of the stimulated area(s). This project is designed to investigate the effects of combining tDCS and MT in patients with subacute and chronic stroke. In addition, one critical question that remains to be addressed is the optimal stimulation timing of tDCS when combined with MT. It is suggested that the stimulation timing may influence the intervention effects of task-specific training hybridized with tDCS. Therefore, this project is also designed to investigate the optimal application timing of tDCS in combination with MT in patients with subacute and chronic stroke. Ninety-nine patients with subacute and chronic stroke will be recruited and randomized into one of the 3 groups: sequentially apply tDCS and MT group (SEQ), apply tDCS concurrently with MT group (CON), and MT with sham tDCS group (SHAM). All participants will receive 40 minutes of MT followed by 30 minutes of functional task training. For the participants in the SEQ group, 20 minutes of tDCS will be applied prior to MT, while tDCS will be applied concurrently with MT for the first 20 minutes in the CON group. As for the SHAM group, tDCS electrodes will be placed on the scalp without actual current output. The interventions will be carried out 90 minutes per day, 5 days per week, for 4 weeks. Behavioral outcomes as well as arm kinematics will be assessed by blinded evaluators before, after, and 3 months post intervention. The behavioral outcome measures will include the Fugl-Meyer Assessment, Revised Nottingham Sensory Assessment, MyotonPro, Montreal Cognitive Assessment, Wolf Motor Function Test, Motor Activity Log, actigraphy, ABILHAND Questionnaire, dual-task test, Functional Independence Measure, Lawton Instrumental Activities of Daily Living Scale, and Stroke Impact Scale Version 3.0. Unilateral and bilateral arm kinematics will be assessed during a forward reach-to-press bell task. Depending on the participants’ capability, an additional forward reach-to-grasp can task will be tested. Kinematic outcomes, including upper limb and trunk movement angles, reaction time, movement time, peak velocity, the percentage of movement time where peak velocity occurs, movement units, and maximum grip aperture will be calculated to identify motor control strategy. To study the possible interaction of treatment group and time of outcome evaluations, group (SEQ vs. CON vs. SHAM groups) × time (pretest vs. posttest vs. follow-up) repeated measures ANOVA will be performed. Additionally, the partial eta square (η2) will be calculated to determine the effect size of interest.

Project ID:PC10601-0855
External Project ID:MOST105-2314-B182-037-MY3