Contemporary clinical psychopathology lacks a clear description of what is understood by consciousness disorders. Although many patients with different kinds of psychopathology complain about alterations in consciousness, neither DSM-5 nor ICD-10 provide a definition of consciousness. Most modern handbooks of clinical psychology fail to mention the subject.

Evidently, clinical psychopathology could benefit from having more clearly defined concepts to study disorders of consciousness. We explore how this has been addressed in the history of psychiatry and psychology. During the nineteenth and first half of the twentieth century, Western European psychiatrists regarded consciousness as the encompassing envelope of psychic functioning and considered disorders of consciousness to be the essential topic in psychopathology. Looking for the main theoreticians of consciousness in the history of clinical psychopathology we mention the work of William James, Sigmund Freud, Piere Janet, Henry Ey and others. This overview is summarized and integrated in the conceptualization of consciousness by Jean-Paul Sartre. He distinguishes four viewpoints in studying consciousness: states, functions, qualities and structure. This framework is capable to qualify a broad variety of clinical symptoms and disorders of consciousness.