Final answer:
Proprioceptors are responsible for modulating the activity of central pattern generators (CPGs), providing information about the body's position and movement to the central nervous system for the coordination of movements.
Step-by-step explanation:
The feedback from proprioceptors modulates the activity of central pattern generators (CPGs). Proprioceptors are specialized sensory receptors located in muscles, tendons, and joints. They provide the central nervous system with information about body position, muscle tension, and the position of limbs in space, which is crucial for the coordination of movement and maintaining balance and body posture. CPGs are neural networks that produce rhythmic patterned outputs without sensory feedback. However, proprioceptive feedback can modify these rhythms to adapt to changes in the environment or the organism's internal state, ensuring that movement is efficient and adaptive.
In comparison, thermoreceptors respond to temperature changes, photoreceptors are sensitive to light, and nociceptors detect pain. Therefore, the direct modulation of CPGs is primarily the role of proprioceptors.