gated
adj.— «The new study suggests that itch, like pain, may be a “gated” system in which signals from other nerve cells can interfere with or moderate the sensation. Scratching the skin near, but not directly on, the spot that itches often provides relief, just as rubbing an aching limb can reduce pain.» —“Scratching Relieves Itch by Quieting Nerve Cells” by Benedict Carey New York Times Apr. 7, 2009. (source: Double-Tongued Dictionary)