Critical psychology is a perspective on psychology that draws extensively on critical theory. Critical psychology challenges the assumptions, theories and methods of mainstream psychology and attempts to apply psychological understandings in different ways, often looking towards social change as a means of preventing and treating psychopathology. Critical psychologists believe that mainstream psychology fails to consider how power differences and discrimination between social classes and groups can impact an individual's or a group's mental and physical well-being. Mainstream psychology does this only in part by attempting to explain behavior at the individual level. However, it largely ignores institutional racism, postcolonialism and deficits in social justice for minority groups based on differences in observable characteristics such as gender, ethnicity, religion religious minority, sexual orientation, LGBTQ+ or disability. Criticisms of mainstream psychology consistent with current critical psychology usage have existed since psychology's modern development in the late 19th century. Use of the term critical psychology started in the 1970s at the Freie Universität Berlin. The German branch of critical psychology predates and has developed largely separately from the rest of the field. As of May 2007, only a few works have been translated into English. The German Critical Psychology movement is rooted in the post-war student revolt of the late 1960s; see German student movement. Marx's Critique of Political Economy played an important role in the German branch of the student revolt, which was centered in West Berlin. At that time, the capitalist city of West Berlin was surrounded by communist-ruled East Germany, and represented a "hot spot" of political and ideological controversy for the revolutionary German students. The sociological foundations of critical psychology are decidedly Marxist.