Psychoanalysis is a method of investigating the unconscious mind to understand mental disorders. It was developed in 1906 and focuses on relationships between conscious and unconscious thoughts. The goal is to make patients aware of unconscious material so they can recover from psychopathology. Psychoanalysis views development as determined by early childhood events and behavior as influenced by irrational drives. Sigmund Freud developed theories of the unconscious mind, id/ego/super-ego structure of personality, and psychosexual developmental stages from oral to genital. Psychoanalytic therapy explores how the unconscious influences thoughts and behaviors. Criticisms include small sample sizes and difficulties testing theories.