Color blindness all variations in human color vision involve the red and green receptors in male eyes. It is very rare for males or females to be "blind" to the blue end of the spectrum. The first scientific paper on the subject of color blindness, "Extraordinary facts relating to the vision of colours", was published by the English chemist John Dalton in 1798 after the realization of his own color blindness. Because of Dalton's work, the general condition has been called "daltonism", although in English this term is now used only for deuteranopia. Color codes present particular problems for those with color
Banner blindness viewers tend to develop a tendency to ignore them without actually fixating on them. Bad marketing and ads that are not correctly targeted make it more likely for consumers to ignore banners that aim at capturing their attention. This phenomenon called 'purposeful blindness' shows that consumers can adapt fast and become good at ignoring marketing messages that are not relevant to them. It is a byproduct of inattentional blindness. Usability tests that compared the perception of banners between groups of subjects searching for specific information and subjects aimlessly browsing seem to support this theory - see study. A similar conclusion