When I first started the vision research laboratory I ran for 30 years at the University of Wisconsin, I experimented with the color spectrum of the fluorescent lights used over the laboratory benches. Those that had more blue and green, more like natural sunlight, clearly made my students feel more relaxed and creative. This was consonant with psychological studies that had shown reds to have more arousing and blue more calming effects humans as well as other animals. Mehta and Zhu have made some fascinating further observations reported in Science and noted in a NY Times article by Belluck which gives examples of similar studies. Work done against the background color red is relatively more accurate, while with blue it is more creative. Here is a clip from the Mehta and Zhu abstract, followed by a graphic from the NY Times article.
We demonstrate that red (versus blue) color induces primarily an avoidance (versus approach) motivation and that red enhances performance on a detail-oriented task, whereas blue enhances performance on a creative task. Further, we replicate these results in domains of product design and persuasive message evaluation, and illustrate that these effects occur outside of individuals’ consciousness . We also provide process evidence suggesting that the activation of alternative motivations mediates the effect of color on cognitive task performances.