Gamma motor neurons are specialized nerve cells that play a crucial role in the regulation of muscle tone and the sensitivity of muscle spindles. They are part of the motor neuron system and primarily innervate the intrafusal fibers of muscle spindles, which are sensory receptors located within muscles. By adjusting the tension in these fibers, gamma motor neurons help maintain the sensitivity of the muscle spindle to stretch. These neurons work alongside alpha motor neurons, which innervate extrafusal muscle fibers responsible for muscle contraction. While alpha motor neurons control voluntary movements, gamma motor neurons fine-tune the muscle's response to changes in length, ensuring that the body can react appropriately to different physical demands.