The dichotomies: psychosis/neurosis and functional/organic: a historical perspective.

Psychosis and neurosis have formed one of the crucial dichotomies in psychiatric classification. This has not always been the case, and indeed the distinction is again being blurred (Cooper 1989). This article will show how the dichotomy arose and how it was strengthened during the first fifty years after the introduction of the term psychosis. The relationship between psychosis and neurosis has not been examined historically, except briefly by Berrios (1987). Lopez Piñero (1983) has dealt with the origins of the concept of neurosis, but his study does not address later issues. The term psychosis was coined in 1845 (Feuchtersleben 1845) to denote 'mental disorder which affected the personality as a whole' and was a subcategory of the then much wider category of the neuroses. The latter were described by Cullen (1784) in the late eighteenth century to denote all the diseases of the nerves and muscles. In 1800, therefore, the neuroses were seen as diseases with a physical cause. The insanities, by contrast, were viewed as diseases of the mind and not generally of physical origin. By about 1900 this situation had been reversed. Most psychiatrists believed that the insanities were of organic aetiology, while the neuroses were of psychological origin, although at that time some psychiatrists and neurologists still believed that the neuroses were caused by organic changes, albeit ones which were not detectable by currently available means, and ones which were therefore referred to as 'functional disorders'. The historical contrast between the so-called functional and the organic disorders will be addressed in this article, as will its relationship to historical and contemporary issues regarding the psychosis-neurosis dichotomy.