You know those eyes are different. Frankly, the eyes that belong to Henson/Muppets have the same organs but they have several differences to most eyes like those. The eyes were created by the Henson team for the Muppet anatomy on a puppet. One of our alien people have ping-pong ball halves and with unique cross-lined pupils on their eyes that are like Kermit; these eyes are completely round and connected from the optic nerves to the occipital lobe of course. The muppet eyes are rarely controlled by the occipital lobe of the brain so that they can be able to have either color vision, black and white or blind/colorblind visuals of muppet eyes just like every eye does. Some muppets have brains at the bottom of the eyes and nerves to it go down to the brain and bring vision signals up to their eyes something like Fraggles, Early Muppet Whatnots, Muppet Frogs, Elmo and others of their cerebral cortex. Everyone has those anatomys because they are needed to be able to view one or more objects. If muppets or anyone doesn't have brains or eyes, they wouldn't survive or be examining anything. So that's why muppets need all those organs to do something or whatever. The note is added to the article.