[Nosology and physiopathology in psychiatry--current aspects of Kraepelin's views on pathology].

Nosological and pathophysiological aspects of psychiatric syndromes in the work of Emil Kraepelin are discussed. A chronological review shows that through developing his nosology, pathophysiological points of view because more and more prominent and nosological aspects got only a relative weight. Considering this background, the still accepted nosology of Kraepelin seems to have only the character of a typology, i.e. operationalizing symptoms on the psychopathological level in order to improve scientific communication. The pathophysiological aspect of a psychiatric nosology, however, allows us to prove--by means of psychophysiological methods--unspecific pathophysiologic mechanisms. These mechanisms characterize the organism affected by a psychiatric illness as having a lower modulatory capacity of psychophysiological systems in comparison with healthy controls. This is demonstrated in the results of the investigations of the Tübingen research group on depressive as well as schizophrenic syndromes.