1878 Jean-Martin Charcot in Diseases of the Nervous System describes the symptoms of hysteria, then considered to be a distinct, biological illness.
1895 Sigmund Freud suggests that dissociation is one of the mind’s defense mechanisms.
1900s American neurologist Morton Prince suggests that there is a spectrum of dissociative disorders.
1913 French naturalist J.P.F. Deleuze describes dissociation as being like the formation of two distinct people—one of them fully awake, and the other in a trancelike state.
1977 Ernest R. Hilgard’s Divided Consciousness discusses the splitting up of consciousness by hypnosis. ...