The recovery of standing and locomotion after spinal cord injury does not require task-specific training

• Published in: eLife Vol. 8
• Main Authors: Harnie, Jonathan, Doelman, Adam, de Vette, Emmanuelle, Audet, Johannie, Desrochers, Etienne, Gaudreault, Nathaly, Frigon, Alain
• Format: Journal Article
• Language: English
• Published: England eLife Science Publications, Ltd 11.12.2019; eLife Sciences Publications Ltd; eLife Sciences Publications, Ltd
• Subjects: Animals; Cats; central pattern generator; Circuits; Disease Models, Animal; Domestic cats; Electromyography; Evaluation; Excitability; Exercise equipment; Extremities; Feedback, Sensory; Felis catus; Female; Fitness equipment; functional recovery; Hindlimb - physiology; Locomotion; Locomotion - physiology; locomotor training; Male; Manipulative therapy; Muscle, Skeletal - physiology; Muscles; Neurons; Neuroscience; Physical Conditioning, Animal - methods; Recovery (Medical); Recovery of Function - physiology; Rhythms; Sensorimotor system; Spinal Cord - physiology; Spinal cord injuries; Spinal Cord Injuries - physiopathology; Spinal Cord Injuries - rehabilitation; spinal cord injury; Spinal plasticity; task-specificity; Triceps surae muscle; Walking Speed; spinal cord injury; locomotor training; central pattern generator; neuroscience; Cat; task-specificity; functional recovery; Felis catus
• ISSN: 2050-084X; 2050-084X
• DOI: 10.7554/eLife.50134

After complete spinal cord injury, mammals, including mice, rats and cats, recover hindlimb locomotion with treadmill training. The premise is that sensory cues consistent with locomotion reorganize spinal sensorimotor circuits. Here, we show that hindlimb standing and locomotion recover after spinal transection in cats without task-specific training. Spinal-transected cats recovered full weight bearing standing and locomotion after five weeks of rhythmic manual stimulation of triceps surae muscles (non-specific training) and without any intervention. Moreover, cats modulated locomotor speed and performed split-belt locomotion six weeks after spinal transection, functions that were not trained or tested in the weeks prior. This indicates that spinal networks controlling standing and locomotion and their interactions with sensory feedback from the limbs remain largely intact after complete spinal cord injury. We conclude that standing and locomotor recovery is due to the return of neuronal excitability within spinal sensorimotor circuits that do not require task-specific activity-dependent plasticity.