Actually your commentor "Smurfy" back in 2006 was close to being correct. The lack of stimulation in color was thought, up through the mid-1900's to decrease violent outbursts in psych patients. Additionally, dark colors were though to create apathy in excitable patients. In the late 70's color alteration was then studied and used by law enforcement in their isolation cells in which "pink" (of all colors) was shown to decrease volinet and aggressive behavior in inmates, where blue was shown to increase it. Kudo's to Smurfy's earliest observation.