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A lot of people were very upset by the prospect that our visual system does not provide us with an image of what is actually being viewed.  That is, when there is a lone yellow dot amongst a bunch of red dots it appears to be red unless it is the focus of attention.  This specific example of the brain producing an image that is not true to “reality” does not particularly disturb me, but it does make me wonder how “smart” the brain actually is.  I think that the brain is probably really good at detecting patterns, but perhaps relies on this ability a little too much.  Then again, it’s only one measly dot on a piece of paper.  Finding out that the dot is actually yellow as opposed to red does not exactly cause my world to come tumbling down.  There are definitely some perks to the eyes and brain being able to work so well together to detect patterns.  We are able to make out what objects are even if they are not illuminated or if there is a strange shadow cast on them.  Also, we are really good at identifying shapes even if they are distorted when they reach our eyes.  That is, if we are looking at a window from a side angle, the corners of the window as we see it do not form 90 degree angles.  The image that is produced on the back of the eye is probably something that has characteristics more similar to a trapezoid, yet we perceive the windows to be rectangular without even thinking about it.  So it seems that there must be more to seeing than just photoreceptors reporting to the brain.  There are basically four things that seeing tell us:  the shape, the position in relation to other things, the color, and the motion or change in orientation of the object over time.  I wonder if each of these characteristics is determined in different areas of the brain.  If one of these areas of the brain were damaged, could the others possibly make up for it or “fill in the blanks” the way the brain does in the dot demonstration?