Psychomotor psychoses - The enigmatic catatonic phenotype

Since the second half of the nineteenth century, disorders of psychomotor behaviour have been described as part of psychotic states. In this respect, the descriptions of catatonia by Kahlbaum and of the motility symptom complex by Wernicke form the historic start of the catatonia concept. In both the German and French psychiatric traditions, psychoses characterised by motor abnormalities and a polymorphic psychopathological picture have been diagnosed in clinical practice until now. In contrast, the current internationally used taxonomies cover catatonia as a subtype of schizophrenia, secondary to a general medical condition or as a specifier of a mood disorder. In this article, the differential diagnosis of the catatonic syndrome will be outlined, with special emphasis on the Wernicke-Kleist-Leonhard classification system. In addition, catatonia in autism spectrum disorders and as part of a genetic syndrome is outlined. Finally, the prevalence of catatonia is discussed. It is advocated to include catatonia as a new diagnostic class in the psychoses chapter of the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5).