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Cover legend: Illustration of the "homunculus" in vision, inviting the notion of a little person in the head looking at an internal picture of the world. Scientists and philosophers discussing the phenomenon of perceptual filling-in often question the wisdom and necessity of painting such internal pictures. An article in this week's Journal describes a functional magnetic resonance imaging study in which the authors did not find evidence for neural correlates of color and brightness filling-in in early human visual cortex, adding empirical weight to philosophical discussion. Note that the gray disks in the picture have identical physical luminance yet appear different in brightness because of contrast with their immediate surround. A temporal variant of this phenomenon, called brightness induction, was used in the study by Cornelissen et al. For details, see their article in this issue (pages3634–3641). Original artwork by Berend Posthumus after an idea by Tony Vladusich.