Representation of visual uniformity in the lateral prefrontal cortex

Visual illusions tend to have early visual cortical correlates. However, this general trend may not apply to our subjective impression of a detailed and uniform visual world, which may be considered illusory given the paucity of peripheral processing. Using a psychophysically calibrated visual illusion, we assessed the patterns of hemodynamic activity in the human brain that distinguished between the illusory percept of uniformity in the periphery (i.e., Gabor patches having identical orientations) from the accurate perception of incoherence. We identified voxel patterns in the lateral prefrontal cortex that predicted perceived uniformity, which could also generalize to scene uniformity in naturalistic movies. Because similar representations of visual uniformity can also be found in the intermediate and late layers of a feedforward convolutional neural network, the perception of uniformity may involve high-level coding of abstract properties of the entire scene as a whole, that is distinct from the filling-in of specific details in early visual areas.