Overview of the itch-scratch cycle.
Activations induced by actively scratching an itch (yellow), main areas activated by itch (red-orange), and major areas of deactivations induced by both forms of scratching are shown (with active scratching in blue, passive scratching in green). Standard Talairach space coordinates (x, y, z). The color tones displayed correspond to Z score values as depicted in the color bars (at the same scale). R = Right; L = Left.