Green vision may be caused by wounds to the cornea or, again, from tobacco scotoma. Blue vision may occur in cases of alcoholism or from santonin poisoning. Following cataract surgery, the patient may experience red vision, sometimes followed by blue vision. Green and yellow are rare. All have a predominance of blue.
Cool colors used with a southern or western exposure provide a soothing, restful atmosphere.
Blue based colors appear to be smaller and farther away than they really are. Cool light at low levels makes things look eerie and unnatural. Cool colors in general are preferred by introverts. Towards green and blue, there is a withdrawal to stimulus. Two colors exceptions are the colors violet and green because both are made equally of warm and cool colors and can be made to look more cool or warm according to the colors they are near.