Perception of the McCollough effect correlates with activity in extrastriate cortex: A functional magnetic resonance imaging study

The McCollough effect is a striking color aftereffect that is linked to the orientation of the patterns used to induce it. To produce the McCollough e ffect, two differently oriented grating patterns, such as a red-and-black v ertical grating and a green-and-black horizontal grating are viewed alterna tely for a few minutes. After such colored gratings are viewed, the white s ections of a vertical black-and-white test grating appear to be tinged with green, and the white sections of a horizontal grating appear to be tinged with pink. We present evidence from a functional magnetic resonance imaging study that the perception of the McCollough effect correlates with increas ed activation in the lingual and fusiform gyri-extrastriate visual ar eas t hat have been implicated in color perception in humans.