Cognitive neuropsychology
Cognitive neuropsychologists use the method of double dissociation when studying the modules of the mind. This is when they use many patients who have had brain damage and try to figure out which parts of the brain are responsible for different cognition. This concept of modularity was developed by Jerry Fodor in his 1983 book The Modularity of the Mind. Psychologists disagree as to how much and which parts of the mind is constructed modules.