Obsessive Compulsive Disorder is defined as a disorder that compels a person to commit ritualistic actions that prevent them from functioning in normal society. Though many speculate about the origin of such a disorder, the most prominent of "arguers," namely Sigmund Freud and Judith Rapoport, claim two such distinct theories for the cause of such a disorder. Comparatively, though Freud's theory of "psychological trauma" shows many examples and probable answers to the origins of OCD, Rapoport's "physiological stimulus" also gives compelling information.

-----Obsessive Compulsive Disorder, or Obsessive Neurosis (as Sigmund Freud refers to it), is seen (by Freud) as an effect of past traumatic experiences. According to him, a person with such a past is then liable to go through unexplainable ritualistic motion often times unconsciously which then debilitate the person from functioning in a normal society.

S. Freud