Green—the color of growth—triggers visionary thinking. In a study led by Stephanie Lichtenfeld, an assistant professor of psychology at the University of Munich in Germany, researchers briefly showed various colors to 202 volunteers before giving them a test of creativity. Those who had seen green generated the most creative responses, as judged by researchers unaware of which colors were shown to the participants. Green in one's surroundings, such as plants, seems likely to inspire imaginative mental processing, whereas other research shows that red is conducive to analytical thinking, the psychologists note.