White's illusion is a brightness illusion. Here, some stripes of a black and white grating are replaced by gray rectangles (see Fig). All gray bars usually have same color and opacity. The brightness of the gray pieces appear to shift toward the brightness of the top and bottom bordering stripes, that is, the gray bars with horizontal black regions on their top and bottom appear darker and those with white regions on their top and bottom appear lighter. But this does not match with what lateral inhibition predicts. This illusion is mostly described for grayscale. A similar illusion occurs for colored patches. This is known as Munker-White's illusion or Munker's illusion.