Rudolph Steiner's work was continued by Theo Gimbel, who established the Hygeia Studios and College of Color Therapy in Britain. Among the principles explored by Gimbel are the claims of Max Luscher, a former professor of psychology at Basle University, who claimed that color preferences demonstrate states of mind and/or glandular imbalance, and can be used as the basis for physical and psychological diagnosis. Luscher's theory, which forms the basis of the Luscher Color Test, rests on the idea that the significance of color for man originates in his early history, when his behavior was governed by night and day. Luscher believed that the colors associated with these two environments -- yellow and dark blue -- are connected with differences in metabolic rate and glandular secretions appropriate to the energy required for nighttime sleep and daytime hunting. He also believed that autonomic (involuntary) responses are associated with other colors.