Robot-assisted arm therapy and brain stimulation to enhance recovery after stroke

Each participant will receive 18 sessions of treatment over 6-9 weeks (3days a week for 6 weeks or 2 days a week for 9 weeks depending on patients convenience) supervised one on one by a neuro-physiotherapist. Each treatment will comprise brain stimulation (real or sham tDCS) for 20 minutes followed by about 1 hour of robotic therapy. Transcranial direct current stimulation (tDCS) is a non-invasive technique that changes the excitability of brain cells by applying a weak direct current (1-2mA) to the brain. The method of applying tDCS involves placing saline-soaked sponge electrodes onto the skin of the scalp. These electrodes are connected to a battery driven direct current stimulator. tDCS is painless, inexpensive, has no major adverse effects and is easy to apply clinically. tDCS has been shown to improve arm function after stroke, with different montages of electrode placement over the affected and unaffected hemispheres (Kim et al. 2010; Hesse et al. 2011). In this study 2mA of anodal tDCS will be applied over the affected hemisphere for 20 minutes prior to arm therapy using the robot. The MITManus InMotion Shoulder-Elbow Robot will be used to provide shoulder and elbow movement training in the horizontal plane. The affected arm will be placed in an arm support trough and strapped in, with the hand grasped around a cone-shaped handle. This robot-arm is connected to a computer. All subjects will perform the same goal-directed activities to improve shoulder and elbow movements in different directions. The robot-arm detects the amount of movement that the subject can perform, and assists when they cannot reach the targets independently. The amount of assistance the robot-arm gives is constantly altered depending on the degree of movement from the subject.