Corticospinal Reorganization after Locomotor Training in a Person with Motor Incomplete Paraplegia

This study investigates how the brain's control over spinal cord circuits changes after robotic gait training in a person with incomplete spinal cord injury. They used transcranial magnetic stimulation (TMS) to stimulate the motor cortex and measured the effect on a spinal reflex. The researchers found that after training, the brain's influence on the spinal reflex changed both when the person was at rest and when they were stepping with robotic assistance. These changes suggest that the brain's connections with the spinal cord were reorganized due to the training. These findings indicate that locomotor training can lead to reorganization of the cortical control of spinal interneuronal circuits that generate patterned motor activity and modifies spinal reflex function after a spinal cord injury.

• 1
  Subthreshold TMS induced a significant facilitation on the TA flexion reflex before training, which was reversed to depression afier training with the subject seated at rest.
• 2
  During stepping, corticospinal facilitation of the flexion reflex at early and midstance phases before training was replaced with depression at early and midswing followed by facilitation at late swing afier training.
• 3
  EMG activation patterns changed significantly after robotic gait training, particularly in the tibialis anterior (TA) muscle, where a burst of activity appeared at the late stance phase after training, which was previously absent.