The Human Central Pattern Generator for Locomotion: Does It Exist and Contribute to Walking?

Area of Science:

• Neuroscience
• Locomotion
• Spinal Cord Research

Background:

• Central pattern generators (CPGs) are known to control locomotion in animal models.
• Their existence and role in human locomotion remain debated.
• Understanding CPGs is crucial for advancing theories of neural control and neurorehabilitation.

Purpose of the Study:

• To investigate the existence and function of CPGs in the human spinal cord.
• To explore the contribution of CPGs to normal bipedal locomotion.
• To inform the development of new neurorehabilitation strategies.

Main Methods:

• Analysis of human studies involving spinal cord stimulation or pharmacological neuromodulation in individuals with spinal cord injury.
• Neuromechanical modeling of human locomotion.
• Comparison of human lumbar spinal cord activity with animal CPG models.

Main Results:

• The human lumbar spinal cord can generate rhythmic muscle activation patterns resembling CPG activity, even without volitional motor control or sensory feedback.
• CPGs in humans can be defined by the rhythmic activity they produce.
• CPGs may contribute to specific activation patterns during the step cycle and simplify motor control during normal locomotion.

Conclusions:

• CPGs likely exist in the human spinal cord and can be identified by their output.
• CPGs may play a role in simplifying motor control and regulating step cycle frequency during normal human locomotion.
• Further research into human CPG operation is essential for advancing locomotion neuroscience and developing effective neurorehabilitation techniques.