Physiological Changes Induced Through MEP Conditioning in People With SCI

Characterization of Physiological Changes Induced Through Motor-evoked Potential Conditioning in People With Spinal Cord Injury

The study team is currently recruiting volunteers who are interested in participating in a brain-spinal cord-muscle response training study that aims to better understand the changes that take place in the nervous system as a result of this type of training. After spinal cord injury, brain-to-muscle connections are often interrupted. Because these connections are important in movement control, when they are not working well, movements may be disturbed. Researchers have found that people can learn to strengthen these connections through training. Strengthening these connections may be able to improve movement control and recovery after injuries.

Research participants will be asked to stand, sit, and walk during the study sessions. Electrodes are placed on the skin over leg muscles for monitoring muscle activity. For examining brain-to-muscle connections, the study team will use transcranial magnetic stimulation. The stimulation is applied over the head and will indirectly stimulate brain cells with little or no discomfort.

Participation in this study requires approximately three sessions per week for four months, followed by two to three sessions over another three months. Each session lasts approximately 1 hour.

Inclusion Criteria:

• Neurologically stable (>1 year post SCI)
• Medical clearance to participate
• Ability to ambulate at least 10 m with or without an assistive device (except for parallel bars)
• Signs of weak ankle dorsiflexion at least unilaterally
• Expectation that current medication will be maintained without change for at least 3 months; stable use of anti-spasticity medication is accepted

Exclusion Criteria:

• motoneuron injury
• known cardiac condition (e.g., history of myocardial infarction, congestive heart failure, pacemaker use)
• medically unstable condition
• cognitive impairment
• history of epileptic seizures
• metal implants in the cranium
• implanted biomedical device in or above the ches (e.g., a cardiac pacemaker, cochlear implant)
• no measurable MEP elicited
• unable to produce any voluntary TA EMG activity
• extensive use of functional electrical stimulation to the leg on a daily basis
• pregnancy (due to changes in weight and posture and potential medical instability)