When choosing a color palette, it is important to consider not only how well they will work when combined, but also the effect they will have. Simultaneous contrast is the effect referring to how the colors interact with one another and change the viewer’s perception. When red and blue are used together, the blue will appear green and the red will appear orange. The human sensation is most intense when two extremes are placed next to each other. To create intense emotion using simultaneous contrast, the result will be more intense when the color scheme used is the complementary color scheme, like the traditional holiday colors of red and green, for example.
via Atlanta Homes & Lifestyles