"This approach builds on earlier work and highlights the importance of the corticospinal tract—which conducts impulses from the brain's motor cortex to the spinal cord and is a major pathway contributing to voluntary movement—as an important target for intervention after spinal cord injury," said Monica Perez of the University of Pittsburgh.
The researchers tested the new method in 19 people with chronic cervical spinal cord injury and 14 uninjured people. The treatment was customized to each individual and paired transcranial magnetic stimulation delivered to a specific part of the motor cortex with electrical stimulation to peripheral nerves found in the wrist.
One hundred paired pulses were delivered every 10 seconds for a period of around 20 minutes to produce volleys of neural activity. The timing of arrival of those volleys in the spinal cord was absolutely essential to the treatment's success, the report shows.