Enhancing Corticospinal Excitability to Improve Functional Recovery

Research indicates that increasing brain excitability might help improve hand function in people with spinal cord injury. Brain stimulation that uses electrodes placed on the surface of the scalp (also called "non-invasive brain stimulation") increases brain excitability and has the potential to make it easier for the brain and nervous system to respond to arm and hand training. The purpose of this study is to compare four different types of stimulation for increasing brain excitability to determine which types are best for helping people with tetraplegia improve their ability to use their arms and hands. To fully evaluate the value of brain stimulation on arm and hand function, the investigators will also evaluate the effect of sham (fake) stimulation. Each participant will receive a single session of each of the five types of stimulation being tested.