The Manicomio General La Castañeda founded in 1910 at the outside of Mexico City, was the most important psychiatric institution of the xxth century in Mexico. When it was open, the families let there men and women whom had the requirement for being considered madness and in consequences, they where appropriate for having psychiatric treatment. In this article I explore the cultural bases of the therapeutic confinement through the imaginaries that the Mexican society of those days had about madness, its causes, symptoms and treatments. It analyzes both faces of madness: the one of the degenerate and the other of the nervous. Both references synthesize psychiatric terms and social variables as class and gender.