Owing to the amnesia that follows episodes of sleepwalking, no secondary revision can be made by the sleeper. This did not prevent Sigmund Freud from taking an interest in the phenomenon. In 1907 he spoke about it to the Vienna Psychoanalytic Society (Nunberg and Federn): He believed that sleepwalking was related to the fulfillment of sexual wishes and was thus surprised that there could be mobility without interruption of the dream life. Finally, at that time, he suggested that the essence of this phenomenon was the desire to go to sleep where the individual had slept in childhood.