Visual Perception - What are we really seeing?

Visual perception takes place all around us we just do not notice it or pay attention to think about it. Let me give you a for instance, is grass really green? We do not truly know. We can also see through one of the visible spectrums which is visible light. There are others that we know of and probably some that we don't. Infrared, Ultraviolet and X-ray are all examples of different spectrums of light. So what is the colour of grass in these various spectrums? I do not know personally but I can tell you that it isn't the colour we see with our very own eyes. The same thing goes for people and animals who are colour blind, they can not see past the various shades of grey, certain animals have themselves some unique outlooks on the world. Kestrels for instance see urination spots of voles in bright fluorescent yellow so that they can track where the vole has been to stalk its prey, everything the else the Kestrel sees is in black and white. Bats themselves as well as moles and various other animals cannot see at all, they are naturally blind and so use sonar or other tracking devices such as smell and small receptors in their whiskers or antlars. There is a certain disease which can affect humans which influences the brains and eyes of the humans which does allow them to see in full colour and see everything a normal human being sees but they cannot tell objects. They can only see a bunch of colours and shapes and lines they cannot tell that they are an object of any sort. For instance a man with this disease said that every morning that we woke up and looked in the mirror he knew he was looking at himself but just could not tell with out having somebody tell him. Which leads me onto my next point about the brain


This all has to do with things we can or can't see with our eyes but a main perception comes from the brain. The brain tricks the eyes in what it sees. Various pictures and diagrams may show some things to be different to what they truly seem like. So it is not only our eyes that create this perception. For instance take a look at this picture.

Your eyes see it as it is but your brain doesn't. At first glance you may think that some of the lines are not straight but sloping a bit making the squares a bit off. But in fact if you look very closely you will find that all the lines are perfectly horizontal and parallel, it is just the position of the squares which is tricking your mind.