Central pattern generators in the lumbosacral spinal cord are theorized to have which of the following key characteristics?

Central pattern generators in the lumbosacral spinal cord are theorized to have which of the following key characteristics?

• A. They require continuous supraspinal input to generate any motor output
• B. They can only produce extensor muscle activation patterns
• C. They can oscillate independently of supraspinal influence and coordinate reciprocal flexor-extensor activity when given appropriate sensory input
• D. They are only activated by electrical stimulation and cannot respond to proprioceptive input

Answer: (C)

Central pattern generators in the lumbosacral spinal cord can produce rhythmic locomotor output without ongoing input from the brain, and they rely on sensory feedback to shape and coordinate the pattern. They’re able to oscillate independently of supraspinal influence, and when appropriate sensory information is present, they organize reciprocal activation of flexor and extensor muscles to produce the alternating gait-like rhythm. This is why this option is the best fit: it captures both autonomous rhythm generation and the essential role of proprioceptive input in coordinating the flexor–extensor pattern. The other ideas imply a dependence on continuous brain input, or a limitation to a single muscle group, or a lack of responsiveness to proprioception, which doesn’t align with how CPGs function in the spinal cord.

Central pattern generators in the lumbosacral spinal cord can produce rhythmic locomotor output without ongoing input from the brain, and they rely on sensory feedback to shape and coordinate the pattern. They’re able to oscillate independently of supraspinal influence, and when appropriate sensory information is present, they organize reciprocal activation of flexor and extensor muscles to produce the alternating gait-like rhythm. This is why this option is the best fit: it captures both autonomous rhythm generation and the essential role of proprioceptive input in coordinating the flexor–extensor pattern. The other ideas imply a dependence on continuous brain input, or a limitation to a single muscle group, or a lack of responsiveness to proprioception, which doesn’t align with how CPGs function in the spinal cord.