Thirty years of research on individual reactions to colors in the environment has produced contradictory findings. Some research has concluded that people who can "screen out" irrelevant information in their environment are not easily stressed out (or aroused) by warm colors such as pale orange walls, whereas "low-screeners" are more aroused by the same orange walls.
New research - Color Effects in a Hospital Room - focused on the effects of colors on the emotions of people in a hospital room. The experiment explored how a patient would you feel in an orange, green, or white hospital room. Which colors would be pleasant or unpleasant, friendly or unfriendly, arousing or calming? It’s worth noting that distinguished faculty in the behavioral sciences and psychology were the authors of the research and that it was recently published in the Journal of Environmental Psychology.
Researchers found that the color of the walls in hospital rooms may very well affect healing and wellness. Light orange aroused all the individuals the most, regardless of their sensitivity to environmental stimuli. Sensitive personalities (low-screeners) reported that white was more stressful than green.
However, the study raises serious questions about the methods. First, the subjects were all college students (mean age 20.4 years). Second, they were asked to imagine that they were recovering from an appendectomy. Third, they were shown photographs of hospital rooms. How can this be the foundation for any kind of conclusive research - and one that is published at that? Sick people are typically older and they don’t imagine the feeling of being sick or recovering from an illness, they are physically traumatized to some degree. Finally, looking at a two-dimensional photograph does not simulate the physical experience of a three-dimensional space with the electro-magnetic energy of the colors bouncing off the walls.
Why even bother with research under these conditions?
I believe that a mildly colorful environment promotes a sense of well being in everyone. At least this "research" found that white walls were stressful.
Source: Individual Differences in Reactions Towards Color in Simulated Healthcare Environments: The Role of Stimulus Screening Ability