The article “What the Frog’s Eye Tells the Frog’s Brain” by Lettvin et al. analyzes the activity of a single fiber in the optic nerve of the frog. This study was done on frogs because of the uniformity of the frog’s retina, the normal lack of eye and head movements, and relative simplicity of the connection of the frog’s eyes to the brain. The study’s initial argument was that the nervous apparatus in the eye itself is dedicated to detecting certain patterns of light and their changes. Upon studying the fibers in the optic nerve, the investigators found that there are four separate operations on the frog’s visual image. These operations that are independent of the level of general illumination includes sustained contrast detection, net convexity
