The early visual system of mammals is made up of neurons that vary their response as a function of surface properties of the stimulus, such as shape, color, contrast, and temporal patterns of stimulation. Therefore it should be true that the perception of these surface attributes is sometimes confounded under specific stimulus conditions. My work explores how stimulus shape can influence the perceived brightness/salience of the stimulus, and vice-versa, by using illusory perception as a guide: these facts result in novel and bizarre salience and shape-distortion illusions. Using computational methods, perception, and awake monkey physiology, these studies identify the mechanisms and levels of the brain in which shape and brightness are processed. Fine examination of responses shows that the visibility of stimuli is dependent on either movement of the eyes, or movement of the world, and that visibility is moreover better encoded neurally by bursts of spikes, than by firing rate or the overall density of spiking activity.