Watch the video above, the trick is nothing short of incredible!
This is due to a mechanism called the
opponent-process theory, which was developed in the 1870s. It is the idea of perceiving color in terms of paired opposites such as red with green, and yellow with blue. The possible scientific explanation for this theory is that bipolar cells are excited by one set of wavelengths and inhibited by other, which are in extend attached to the cone retinal receptors.