Optimizing Cortical Priming

Each year over 795,000 people suffer from stroke resulting in the primary cause of adult disability. Persistent upper limb dysfunction due to stroke significantly impairs performance and results in a serious decline of quality of life. As most daily activities involve the use of both arms, restoring the coordination between upper limbs is essential for regaining functional independence. Only a few interventions have been designed for improving function of both arms, and most of these interventions have focused on movement retraining without directly facilitating the injured brain. The purpose of this study is to design and test a noninvasive brain stimulation protocol tailored to enhance the coordination between the arms in individuals with chronic stroke. The investigators propose that the dorsal premotor cortex on the noninjured side of the brain (cPMd) could serve as a potential stimulation target for enhancing arm coordination and brain function. In the first part of this study (Aim 1), the investigators will examine its effects on modulating arm movements in individuals with chronic stroke. In the second part of this study (Aim 2), the investigators will upregulate the activity of the most responsive region (cPMd or iM1) of each participant prior to arm movement training (bilateral arm training, BAT) to determine the combined effects on augmenting bilateral arm coordination and brain function in individuals with chronic stroke.