Gate system for pain control is located at

(C) Both > The dorsal horn represents a "gate" in which impulse in the sensory nerve fibers are translated into pulses in ascending tract, and it appears that passage through this gate is dependent on the nature and pattern of impulses reaching the substantia gelatinosa and its environs.> This gate is also affected by impulses in descending tracts from the brain.> The synaptic junctions between the peripheral nociceptor fibers and the dorsal horn cells in the spinal cord are the sites of considerable plasticity> For this reason, the dorsal horn has been called a gate, where pain impulses can be "gated", i.e., modified.