[An outline of the catatonia concept of the Wernicke-Kleist-Leonhard school of psychiatry].

Following Wernicke and Kleist's footsteps, Karl Leonhard developed a detailed nosology of psychomotor disturbances occurring in endogenous/functional psychoses. In Leonhard's classification the good prognosis cycloid motility psychosis is distinguished from the group of systemic and non-systemic catatonic schizophrenias. The diag - no sis of both types of catatonic schizophrenias is based on the recognition of a specific catatonic sign/symptom coupled with less specific, yet relatively stable other psychiatric symptoms forming unique Gestalts of psychiatric syndromes, or disease entities. These catatonic subtypes can be easily identified with practice and guidance by an experienced clinician. Apart from periodic catatonia, the other Leonhardian catatonia subtypes have never been subjected to syste - matic validation studies. The late Bertalan Petho refined the clinical description of catatonia in Leonhard's nosology and contributed to their clinical validation by conducting long-term follow-up studies.