Historical and conceptual aspects of motor disorders in the psychoses.

Historical epistemology is a useful method to understand the longitudinal construction of the movement disorders in psychiatry. Four periods can be identified in such a process. The first, extending from Classical times to the work of Griesinger, included disorders such as catalepsy, crocidism, epilepsy and paralysis. The second period, stretching from Griesinger to Kahlbaum, concentrated on the study of melancholia attonita, stupor and catatonia. The third period, covering the time from Kahlbaum to WWI, witnessed important conceptual shifts such as: the transformation of madness into psychoses; the redefinition of movement and motility in psychiatry; the appearance of self-contained syndromes as dyskinesias, tics, akathisia, complex disorders like the cases of encephalitis lethargica, etc.; the advent of functional and psychodynamic explanations; and the description by Wernicke, Kleist and others of the motility psychoses. The fourth period stretches from WWI to the present and since it corresponds to the views and work reported in the rest of this Special issue it has not been touched upon in this paper. In spite of an increasing methodological refinement, empirical research is yet to clarify what is the clinical meaning of the movement disorders in the context of the psychoses and to explain whether such disorders are primary (i.e. issuing directly from the brain and parallel to the rest of psychotic symptomatology) or secondary (i.e. mediated by cognitive and emotional phenomena characteristic of the psychoses).