Lightness Constancy Research Paper

Prompt 2. The purpose of this paper is to discuss the lightness constancy and how it works. Including how the visual system works with constancies, to properly attribute uniform color to a surface. The way to go about the task is with an example. Imagine there are two surfaces next to each other. One appears uniformly white since the light source is evenly distributed throughout the surface. The other has surface patches, a non-uniformity in the light being reflected off of the surface. So there are two proximal stimulations that are very different. Regardless of differences, both surfaces will be attributed uniform whiteness accurately. The goal is to figure out how two different stimulations can be attributed the same property. Which is …show more content…
First I will discuss registration. Registration works well in registering the luminance through the proximal stimulus. It takes in the luminance and may register some discontinuities in the signal. But it does not account for all of the information of the proximal stimulations. Registration cannot receive the non-uniformity example and distinguish what belongs to the reflectance or the illumination. The registration cannot do so because it only registers different light intensities. A bank of light comes in and the neurons fire in response to the light rays. Then the registration groups similar light intensities to form patterns. Registration has rules for what qualifies a light intensity to fit into a pattern or line. This gives rise to the registration of edges. But there is no distinction of the type of edge beyond that it is an edge. The registration does not go much further than taking in the information and sorting it. To get the full story of how the example works, one needs more than just registration. So there must be a second distinction between registration and perception. Which is the fact that the registration does not deal with veridicality conditions. To properly describe the constancy that is at work, there have to be veridicality conditions. Professor Burge believes veridicality conditions are what sets representation apart from pure registration. Veridicality is the ability to represent …show more content…
First is that unlike registration, the perceptual system actually does distinguish between illumination and reflectance. The visual system can attribute uniform whiteness to the example of proximal stimulation with surface patches. It does so by determining what belongs to a change in illumination versus reflectance. The perceptual system can determine the surface patches to be from a change in illumination. If it does, then the perceptual system attributes uniform whiteness to the example with surface patches. The perceptual system does so with cues, which will be discussed further in the next paragraph. The second thing that sets perception apart from registration is it can fail in representing. Burge believes that perceptions are representational in a distinctly psychological sense. In order to have a genuine perception, there has to be a possibility to misrepresent. This is where the veridicality conditions play an important role. Veridicality is important to lightness constancy because the perceptual system makes a choice. In making a decision between reflectance and illumination, there needs to be opportunity for error. It is possible for the visual system to be wrong in attributing properties to a particular. But the fact that it can be right can mean there is possibility of genuine perception. Registration cannot have genuine perception, because it cannot perceive in the first place. So unlike