Repression is one of the Freudian concepts which recurs in Hitchcock's films. According to Freud, "the essence of repression lies simply in the turning something away, and keeping it at a distance, from the conscious". Freud believed that traumatic memories, usually of childhood events, are repressed by the conscious mind; this is a defence mechanism which keeps the ego free of conflict and tension. These memories remain hidden in the subconscious, and manifest themselves in the neuroses and psychoses of the individual, when something induces the momentary retrieval of a repressed memory, triggering a neurotic or psychotic episode. One aim of Freudian psychoanalysis is the retrieval of these repressed memories from the subconscious, in the hope that confronting them will cure the patient's neuroses.Most of us were probably first exposed to the general ideas of Freudian psychology in Hitchcock films, and they're still valuable tools in understanding the concepts.